Onan GHAB RS12000 Generator Set

We had a thread last year about the Onan 12000 genset acting up in cold weather. Evidently it uses a Honda Vee twin engine A GRX 650 or something like that. If you can identify who the engine manufacturer is you can probably get an OEM service manual for it. Secondly it is probably possible to identify the oil presure sender just by physical examination. Presure sensors of necessity have to be mounted in an oil gallery. These show up clearly on most castings and are typically located down low on the crancase part of the engine block. The Honda engine by itself is fine. The trouble seems to be in how Onan / Cummings modified it for their generator setup.

Thanks Elnav,

I have been searching around for that LOP sender without much luck. Onan built a pretty tight enclosure for this gen set. I was hoping someone might at least know which side the thing was on. I guess I will wait till things warm up a little and then do a better look see.

Good luck,
John

Thanks,


If I can find the lop switch, I will install a by pass on it so I can start the engine and get the oil pressure up and warm enough to trip the lop and then re-enable the switch.

I found the engine model. It is a gx670 honda I think. I am looking on the web now for a picture of where the switch may be.

Johnds

Have you downloaded the Honda service manual from:

http://www.honda-engines.com/Engines_owners_manuals/ownersmanuals/gx670.htm

They ask that you be specific on your serial number. My guess is that if you do, they will tell you to contact Onan so just pick any generic model. This engine has a spin on oil filter. Guaranteed the oil pressure switch will be in the near vicinity of the filter mount.

Good luck

I found an onan parts manual online. I think you are right about the lop switch being near the spin on filter. I have to remove a cover to get to the base of the filter housing. I am betting the switch is there as you say.

That said....now I have to find out from onan why there is only a 3 second delay before shutdown instead of the 10 second delay they talk about. I think if I got the full 10 seconds, this would not be a problem.
Thanks,
Johnds

I just checked. That other thread was started Feb 19 2008 by Anned. They described the genset as Onan RS12000.

We had a similar problem with a Catapillar diesel unit. We installed a resistance heater system on the coolant jacket supplied by Cat. After that had no problems with cold weather starts.

HI, burt!

Quite true. While elnav discussed the initial flow of lubricant through empty channels due to long periods of non-use, he neglected to consider lubrication temperature as the probable cause for higher viscosity. Johnds reported that when engine was warmed through, it ran fairly well. The warming through would affect the viscosity of the lubricant so that running through the lubrication channels becomes a less-forced process.

The heater system being installed on the coolant jacket and run prior to startup seems a likely solution as well. It works on automobile engines in the winter for cold starts, too.

GA

Mark

down in the oil patch we have more trouble with the fuel gelling at 15 degrees than anything else

Well, if the diesel is too cold, you could just add 10 to 15% petrol to the diesel during the cold months without ANY harm done!

That depends upon the diesel pump design and or the injector design. Some modern units will get damaged by the petrol in the diesel due to it not being a good lubricant.

Old designs are usually not affected quite so much....

Be warned!!!

ITS THAT THE OIL IS TOO COLD TRY JUST USING A HEATING BLANKET OR BUY AN OIL WARMER. EASIER THAN REMOVING SAFETY PARTS.

Thanks for the ideas folks. I forgot to mention that this is a propane powered unit. It has 5w-30 synthetic oil in it and it starts right up with no problem. The problem is that when the OAT is less than 15f, the Low Oil Pressure switch is not sensing the oil pressure soon enough and the auto shutdown is killing the engine within 3 seconds of start up rather than waiting the advertised 10 seconds before making that call. As soon as the weather warms up, I will trace the wiring to the LOP sender and add a temporary disable switch in that circuit. This seems to me to be the easiest way out since Cummins/Onan will not talk to me.

Good luck,

Johnds

Murphy Gages of Great Britain sells a starter relay that can be used to manually control the delay. It consists of a relay that controls the fuel shut-off valve. The relay is tripped (killing the engine) when a signal goes to ground (i.e., normally closed oil pressure switch). It is fitted with a button to over ride the automatic shutdown on startup- one depresses the button until the oil pressure reaches the level at which the oil pressure sensor opens. Once the button is released and the engine is operating normally, the normal safety features are activated. Very easy to install on most gen sets, but the enclosed Onan may be a bit of a challenge...

It is not uncommon for these types of generator sets to be furnished with a block heater as well as a crankcase heater. Perhaps yours has one. If not, you can get those "dipstick" heaters that go in the tube where the dipstick for checking the oil goes. You then plug it into a 115 volt outlet and it keeps the engine warm. That may help.

The dipstick heater is a possibility. Thanks for the idea.

Johnds

One thing about gensets - especially emergency power units. You normally do not need to start them until the power is out. So relying on AC powered heaters for the block or the oil pan is perhaps impractical. Last year's discussion about this same engine/generator revealed that the engine would blow out the crank shaft seal after a few hours of cold running. It was propane powered and was used only when the solar panels failed to provide a charge to the off-grid home. Here again was a case of the propane powered genset having to start under cold winter conditions. The fact the oil seal would blow out not once but three times indicates the crank case cavity would get pressureized. Reviewing the thread shows the owner not having any luck with trying to get an explanation from Onan. I learned that Onan eventually suggested replacing the 12000 watt genset with a 15,000 watt genset using a liquid cooled engine. But the owner incurred considerable expense in doing the change over.

Another reason NOT to buy from this company!!

Can you find an oil gallery and temporarily install a manual oil pressure gauge and watch during start-up and see if it really is low oil pressure? I sounds like you are on the right track, but if it is something else this may save a headache or two. -- JHF

Hi, JHF!

The galleries run throughout the entire drive system, and are composed of very tiny (relatively speaking) channels moving, for the most part, at high speeds. I don't know of any sensors that one could use to monitor them; and as well, blocking one with a monitor would impede its flow. So a manual gauge is not a possible option.

There are often meters on the lubrication entry points that track the amount of lube used, and one might try timing the changes in the entry of lubricant in some manner, I suppose.

Mark

I doubt very seriously if anyone dislikes Lawyers any more than I do. BUT: If your genset has the troubling problem of blowing out oil seals, it would likely be from propane leaking around the piston rings or cylinder head gasket into the valve covers and migrating to the crank case. If this occurs, it only takes a little leakage around the rings to permit hot combustion gas from also igniting the propane in the crank case. It would only take a single pop to create enough pressure to blow the seal out. This would constitute a safety issue, and your lawyer might be willing to send a letter to Onan on your behalf. You may end up with an up grade at no cost to you but the time for your to send the letter. You should not need to retain the Lawyer just to have the letter sent on your behalf.

TMF

Hi, Toomuchfun!

Conguruatulations on your new status! Now, we will all have to give you, as a guru, a much larger respect for all your future contributions.

"it would likely be from propane leaking around the piston rings or cylinder head gasket into the valve covers and migrating to the crank case"

How would this leakage occur in such a way that Onan could not point out to you in reply that it was due to a lack of proper maintenance (unless it were to be a brand-new machine)?

Mark

Thanks for your response! As for my reply, it comes from experience. The Cylinder walls are likely dry from lack of use, The rings are made of one or more steel products, likely at least two as the oil sealing ring is different from the compression rings as they are generally a little different in design. As for the cylinder it self it may be an aluminum alloy, iron casting machined or possibly sleeved with a steel liner.

The owner states that the temps. are very cold. These above materials will all shrink due to the low temps.. Also they will likely shrink to different dimensions than under normal use. The difference in compression sealing could be just enough at these very cold temps. to permit just a little propane to slip around the rings when under compression. It would not take very many revolutions to permit just enough fuel gas to slip into the crank case to make it an explosive mixture. An ignition in the cylinder, that would permit just a minimal amount of exploding gas to reach around the very cold rings could cause the explosion. I have had a lawn mower explode that way because the gasoline mixture found its way into the crank case because the oil seal rings needed to be replaced, and I neglected to take care of the matter.

As for the Guru that is just fine with me if I can be of help to folks. I seek nothing in return and that includes popularity.

Joe TMF

Interesting idea about vapors in the crank case. Hopefully since this engine is designed for propane use they gave that some consideration when designing it. The rings must be making good contact since the motor fires instantly even when it is 15f OAT. I will modify the LOP circuit like I talked about when the weather is better but it may be a while before I get to try it out since the weather here does not often get that cold although I have seen temps here as low as -20f OAT.

Here are a couple of photos of the unit if folks are interested.

http://jsadie.com/ebay/genset1
http://jsadie.com/ebay/genset2
http://jsadie.com/ebay/genset3

Hopefully I will find the LOP switch behind the shroud surrounding the oil filter.

Good luck to all,
Johnds

Johnds; your links did not work for me.

Google says no results found and the links do not work directly.

You have to copy each link, one at a time, and paste it into your browser address bar and then hit go. I tried it for each link and it worked for me. If you still have problems let me know and I will email you the pics if you like.

It was the only way I could see to post a picture since I am new here.

Johnds

That is what I did first try. Copy and paste into Google. I will try another browser

Okay. changing browser worked. Your second picture shows some wires peeping out from under the shroud. I would bet these are for the oil pressure switch. Now trace them to the control box.

As an experiment try a hair dryer on HOT to heat up the Low oil pressure switch itself to see if that changes the delay interval. It could be something as simple as poor mechanical tolerances inside the sender itself. If the sender is only an inch in diameter its a snap action switch. If the sender is more like 2" diameter and just as long then it is an analog sender with a variable voltage output in proportion to actual pressure. On all the gensets and diesel engines I have worked on, most of these senders are simple snap action switches. If that is the case then the control board has a delay circuit. Analog delay circuits will have a trim pot but more modern ddesigns may have a digital delay using a clock and divider circuit. Trim pots are notorious for vibrating loose and changing their settings. Especially if the pots have not been sealed after factory adjustment.

The wiring diagram shows a switch that goes to ground so I suspect this is a simple on or off switch. I am not anxious to start messing with the controller board even though it is short changing me on the delay time. I sure wish Cummins/Onan would be a little more helpful.

Good luck,
Johnds

John you got as much snow as I have. What part of the country are you located in?

I live near the Columbia river about 70 miles east of Portland, OR. It has been several years since we have had winter here though but it looks like its back this year. Looks like more to come on Saturday and Sunday.

Johnds

I'm quite a bit north of you at lat 53 D 30M near Prince George. Right now its -23F and we are bracing for another foot of snow over the week-end. Thank goodness my snow blower doesn't have a starting problem.

Hello johnds.

Regarding your assumption that the engine was designed for propane use, Almost any gasoline engine can be adapted to run on propane. There is a company in Dallas, Texas that sells the parts to convert most any engine for that fuel. There are plans around for the modification of small engine carbs. to use propane. You can get inventive if you like, and get a pressure regulator and the adjustment valves from a propane grill and make your own. The good side of using propane is it never gets old and never gums up the carb. when not used in a while. Propane will be just as good a fuel 50 years from now as it is the day it was delivered. However propane is a dry fuel and therefore contains no lubricating qualities as does gasoline of diesel fuel. This means that those parts that desire to get just a little slippery stuff won't. the result is that the time between overhaul is shorter.

Just another note regarding the shrinking parts. The rings all have a gap in them so as to be stretched to get them on the pistons in the first place. When the piston including rings in place are installed the rings compress but that doesn't mean the gap closes completely. there must be a small gap so that when the rings get hot and expand they close to with in tollerence. Gasoline and diesel are denser than propane and are less likely to pass very much of it through the tiny gap at the ends of the rings.

I hope this helps!

TMF

And a GA 4 U my friend.!!

If you have propane at the unit, why not use a weed burner torch to warm up the oil pan?

HA! HA!

To my way of thinking, the oil pump is almost certainly a positive displacement pump and will develope pressure a lot quicker and higher during cold weather. As to the switch if it is spring loaded or a bourdon tube type I can't see the connection.

Here in Maryland 15 degrees is about as cold as we allow except for the occasional excursion below zero so I can't make a comparison with my Onan installed in my motorhome. I do know that if I don't use the inlet air heater it isn't even going to start. I agree with you that going out there and messing with that thing in the cold is probably unecessary if you can get it going with a sufficient amount of swearing, kicking and cranking.

Hi all,

I give Elnav a GA for all his posts. If you can locate the terminal for the LOP on the control board then why not attach a wire tail as a test and ground it down until the unit is running smoothly? If it is manual start then you can just fit a momentary action switch to do this when necessary.

Onan may not provide telephonic advice but why not try a dealer, they are often more forthcoming as they will not be mired in corporate legalities.

We have a lot of butane powered sets here and a problem often suffered when cold (32F) is that the evaporation in the tank causes the pressure to drop and shuts the set down after a short period. The usual solution is to either keep the bottle in a warmer place or double up the bottles so that the evaporation is slower and causes less cooling. I don't think this is your problem but the symptoms are sufficiently similar that it is worth keeping in mind in case the LOP is not the problem.

Regards

Chas

The Honda motor has a low oil sensor which is probably causing your problem because the oil can not drain back to the crankcase when it is cold and is shutting the engine down to protect it from running low on oil. You can probably just add another 1/2 pint of oil therefore giving the oil longer to drain back but will still not be so high of a level that you start having a problem with the crank whipping the oil up and causing problems.

Hi....I've installed several stand-by units and have encountered a similiar problem. I believe your assuption that the unit is forcing a shutdown due to a faulty low or no oil pressure switch. As you mentioned Cummins powered, I assume this is a water cooled unit with a radiator. A simple solution might be to get a simple electric screw-in block heater ( to keep the coolant temperature, hence the oil temperature as well, at a level that will overide the shutoff signal from the oil pressure switch.) This might not cure the problem but it seems that once the unit runs until it attains operating temp, you are ok. Just a thought. Let us know if it works. Lamar Bailey....Commcon, Inc.

If you have recently changed to the synthetic oil, it is possible that the older oil is still trapped in the "dead end" of the oil pressure switch. The tiny hole in the OPS would slow the transfer of oil to the diaphragm of the switch. You could try removing the OPS and allowing the oil to drain back out of that passage. Then clean out the OPS with mineral spirits till it appears clean. Reinstall the switch and the trapped air pocket might trip the switch faster. A cheap easy trial. Good luck.

Bob C,

That is a good idea. It has had synthetic oil in it for a couple of years but cleaning the switch is a good idea. The sticker in doing that is being able to test the switch after cleaning. I would have to wait for who knows how long till the weather gets down to 15f again to see if anything changed. When I finally get to the switch and trace the wiring, that circuit will have a bypass switch mounted someplace so I can temporally disable that function. That totally solves the problem with no guesswork.

This is an air cooled system btw.

Best to all,
Johnds

Hi Johnds, Did you ever figure out whether or not it was the LOP switch? Did you change anything? I've had my Onan 12000 for six years now and have just over 1900 hours on it. We live off the grid in northern BC; the cold winter weather has caused me hassels for every one of those six years. Usually, I can heat the generator shed up, thaw out the genny, and away it goes. Today, however, it's doing the 3 second shut-off that you mentioned (even though we are finally 'warm' at -13C; we were down to -30C for a while there). We've been heating the shed today for the past two hours but thus far, no joy. I did a minor service on it; it seems to be getting old. The spark plugs were quite fouled and I discovered that the service guy (I broke down last week and called for help even though the local Cummins folks don't know much about Onan) that was here neglected to replace a number of parts on the air filter. Does anyone know how many hours these gennys will last, with a bit of TLC? Finally, if one were going to replace their heavily-used back-up generator (we have solar panels and a wind tower as well), what brand would people recommend? I plan to go surfing through previous threads but just joined today. Thanks in advance, A

Hey Offthegrid where are you located. I'm in Hixon just south of Prince George. Gasoline engines will typically last 3000 - 6000 hours between rebuilds depending on loading. My wife's uncles get over 10,000 hours from their diesel gensets. Bill runs a resort on Babine lake and runs the genny from 6:00 AM to 11:00 PM seven days per week. 52 weeks per year. The other uncle lives off-grid and his genset starts on demand according to state of charge on his battery bank. Regarding replacement. Are you dealing with Maxwell Simpson in PG? If you are off-grid do you really need a genset as big as the RS12000?

Thanks for the information. Our Onan is a propane powered model; bought it with the whole-house off-the-grid system. It is supposed to turn on automatically according to low battery voltage but it rarely works in cold weather. We deal with Energy Alternatives in Victoria - they have a rep here in Smithers but neither of them know much about generators. Everyone seems to know about diesels but... There's a Cummins rep in Smithers as well but, again, they don't really deal with gennys. Will try the hairdryer trick. Have had a heater in the genny shed most of the afternoon but nothing seems to be working, although the rev'ing has gone from 3 seconds to its automatic turn-off time of 20 seconds. Will have to plug the hair dryer into my truck though as our batteries are nearing their complete shut-down voltage. :) Have never had this long of an issue; usually heat does the trick. If we could get by with something smaller, that would be great. Replacement on this puppy is over $7k. Lousy way to start the new year! Again, thanks for the info! Cheers, A :)

Offthegrid,

I have not yet searched for and installed a bypass on the lop switch. I am waiting for the snow to go away and the temps to rise before doing that. I am 99% certain that the lop is the problem.

It is interesting to hear that you are experiencing the same problem of the genset shutting off after 3 seconds when it is really cold. After leaning that, I believe that the control board has a design flaw. The manual for my genset says that there should be a 10 second delay.

Are you running 5w-30 synthetic oil in your genset btw?

If I were be buy another genset, I would make sure that it was from a company that would provide some technical support for it. I am disappointed with the lack of response from cummins/onan.

Best of luck and stay warm,
Johnds

Johnds and Offthegrid : Well the symptoms are consistent. I'm now wondering if the time delay is determined by a bimetallic strip device. This would be the simplest time for 10 seconds I can think of. Under "normal" conditions the ambient temperature would allow the bimetallic strip to cool off in around 10 seconds but with the extreme cold we are now experiencing the extra cold woudl cool off the strip faster - giving you only 3 seconds. delay. As a quick test, try heating up just the control board where the delay time is suspected to reside. Use a hair dryer, that will get things warm but is less likely to fry anything. If that extends the delay and allows the motor to stat and run and continue running, you now know what to fix. There are solid state relay times from companies like OMRON P&B Guardian , etc. with programmable delays. Most use an RC timer network but the real digital units use a clock and diverder circuit. Way more expensive but it may be necessary. Another solution I remember from my early days of playing with military equipment is to place a heater enclosure around the delay timer on the control board. I suspect the Onan designers were designing for a mid west or Florida environment and really didn't do product testing for extreme cold conditions like we have up here in BC this winter. Elnav

Hi Johnds, No, just running regular 5W-30. Have just switched over from 10W-30. It worked fine twice since then, and now nothing. Argh. Cheers, A :)

I just found this link on another discussion thread.: - the pressure will be the vapor pressure at that temperature: http://www.engineeringtoolbox.com/propane-butane-mix-d_1043.html If you follow the link and scroll down, there is a graph giving vapor pressure for propane at various temperatures. The graph indicates that zero pressure occurs at -44C but at -30C the pressure is still very low. I have not found what the pressure regulator on a propane powered engine is set for; but it stands to reason that tank pressure must be above the regulated set point in order for fuel to flow into the mixing box ( replaces carburetor) on the engine. Needless to say a propane powered genset installed in extreme cold climates will not start when air temps chill the fuel tank below a critical point. I'm surprised to find Onan gensets recommended and installed as emergency power by companies when they know that particular location is going to get so cold.

That is good news. I could swear that I recall seeing the OAT at -30f the first year we moved into the house many moons ago. I would consider -20f a realistic planing temp. I guess if things get really bad I could point the propane torch at the 500 gallon propane storage tank to get things moving.

Best to all,

Johnds

As far as we are concerned you are located in southern warmer climate compared to us. I'm located about 1000 miles further north than you are. Hot air balloonists have propane bottles with 120V heaters imbedded in the tanks. I thought I was imagining things first time I saw that. I asked around and was told the huge burners going full bore during initial inflation, burn so much propane so fast they frost up and can actually freeze themselves into stopping. Being on the ground at that point, they also have access to a genset that drives the fans also used during initial inflation. So they plug in the tanks for heat. For extreme cold weather use I was thinking of somethign like an electric blanket or other heater around the propane tank and a very small gasoline genset just big enough to drive the heat blankets. Gasoline gensets can start in colder weather than a propane unit can. But you really don't want a gas genset as emergency power on an ongoing basis. It becomes far too expensive in fuel burn for prolonged running.

I am probably going to open a whole new bag of worms here.....but I believe that the synthetic oil will give you more slickem, a highly technical term, when you first start. I was also told, for someone like me, that does not use the genset much, that the synthetic oil will absorb less moisture when sitting idle.

Best to all,
Johnds

Exactly the advice I was given by my mechanic guru. He has done a lot of genset service in his time. Also ran a independent service station for 10 years.

I have the same problem with my RS1200 when it gets colder than freezing. We didn't have any electricity outages here in the mountains until the second winter, so that's when I discovered the problem. When I re-tested it before the warranty was up, it was warmer and there was no problem. However, when it gets cold and snows, I always have a problem keeping the generator running more than a few seconds. I rebuilt the carburetor (pressure regulator) and cleaned out any propane oil gook and put an inline filter from Onan on the propane line. But I still had the same problem when it was cold and I actually needed the generator. It always died - as though it were starved for fuel. The longer I waited before re-trying, the longer it would run - but often only a couple of seconds. Finally I believe I've found the problem. I disconnected the propane feed hose from the carburetor (the slip joint is inside the side panel at the Acme Carburetion solenoid) and watched what came out of the hose when the starter was running and the solenoid was actuated: almost nothing came out. I didn't want to leave the starter cranking while I inspected the little fuel that came out, so instead I jumpered the plus side of the battery to the side terminal on the solenoid (the top solenoid terminal is negative ground). As the solenoid warmed up from the current flowing through it, it gradually opened more and let more fuel through. Upon reconnecting the fuel hose to the carb, everything ran fine. I then removed the solenoid and tore it down, thinking it might be faulty or dirty inside. The only anomaly I found was some aluminum shavings from the machined housing were on the valve seat - which allowed it to leak a tiny bit when it was supposed to be closed. This explained the slight propane smell I noticed around the generator when it wasn't running and also that the generator would run for about 10-15 seconds the first time I'd try to start it in cold weather but only for a couple seconds on subsequent tries. The steel piston that released the valve diaphragm had plenty of clearance, so that wasn't the problem. I talked to Acme Carburetion about it and they suggested making sure the solenoid was getting 12 vdc WHILE THE STATER WAS CRANKING. However, I don't think that was always my problem, because many times the gen was running post-starter before it died. I believe the problem is the solenoid not opening properly in cold weather or freezing up when the propane expands. I may install a button to jumper 12 volts to the solenoid and manually hold it down for a while before starting the generator in cold weather, heat the solenoid with a hair dryer or replace it. New solenoids (Model 4004A) are available from Acme for about $35. My suggestion - before blaming the oil pressure sensor - is to make sure your propane solenoid is actually opening and providing fuel to the engine (being the hose is well vented away from the generator and any possible spark or flame!).

If your gen-set is diesel, I would say that you are gelling and would best be served by a fuel mix of 60% diesel #2 and 40% #1 and you will be fine to about 10 below. You can also go with #1 if you add marvel mystery oil to it as well for lubrication to the injectors

Hi John,

this probem has a relatoin with coolant temp. not oil pressure .

you must check the setpoint of low coolant temp. in the protection devices , and the

time delay of shutdown protection .

Goodluck .

Hi,

This is an air cooled propane fired genset.

Johnds

Hi, johnds!

Y'know, this is a strange idea, and probably has nothing to do with your problem, but in another blogset, some advisers I had contacted from the "ask the experts" option in an electrical website were invited to comment on outdoor gensets; and one of their comments was that the concrete (or other, I guess) genset mounting slab can freeze and cause early cutouts by offering an alternative ground in very cold weather.

Just thought I'd throw that thought into the mix.

Mark

Could you expand on that?

How about a link to the blog?

In general I wonder as to the rationale of that argument. The electrical code already requires solid grounding of the genset frame and the grounded neutral conductor. A fixed installation shoudl have a ground rod plus heavy conductor installed.

In practical terms the DC starting circuit has the negative bolted to the genset frame, thus forming a pretty good ground itself. Sound proofing practices makes it almost mandatory to install rubber cushion mounts. In ships these are installed on a conducting steel deck. Much better than frozen concrete.

So how does a ground in parallel with the ground consitute a problem for control and alarm circuits? Sensors either conduct to ground or they are totally isolated.

I'm not nit picking, just very curious. I work with designs incorporating gensets that are very well grounded. The logic is not clear to me at this point.

Those are good questions elnav.

My genset sits on pressure treated timbers and is WELL gounded. That said, I guess anything is possible. It will soon be warm enough for me to get out there and install a cutout switch in the LOP circuit. Then all I have to do is wait till the next time the oat reaches 15F to see if in fact that was the problem.

Good luck,

Johnds

That sounds like another version of the story about how batteries go dead when they sit on concrete. Concrete sucks the life out of batteries.

That notion or folk lore most likely stemmed from the fact the concrete acted as a heat sink which in turn reduced the electro-chemical activity. This was seen as an apparent lowering of battery capacity.

Back around 1968 - 1973 I was responsible for battery room maintenance. It was stressed that all batteries had to sit on strong wooden shelves. Even when we had to place them on the floor they had to sit on wooden slats to prevent contact with the concrete. <grin>

Hi again, Just to let you know what happened with my generator... I spoke with Onan in Kamloops, BC and they had a tech working in Prince Rupert who would be passing through my area in early January so they asked him to stop in and take a look at our generator. This fellow was amazing. He was very nice, very patient, and had no trouble doing the overhaul while explaining everything to us as he went. Turned out our problem was two-fold: 1) probably the propane is getting just too cold and it's causing problems and 2) the valves were very tight. He reset the valves, took the rest of the genny apart to inspect it all, suggested we replace the brushes some point in the near future, and suggested we use synthetic oil. I mentioned a lot of the info from this thread to him and he said that nine times out of ten, it's the valves. Since then, we've had nary a problem with our genny, even in the cold weather, knock on wood! And our motor is an original Onan. He said they used Hondas for a while until they switched to their latest Subarus. Cheers and good luck, A :)

I suppose you are feeling all warm and fuzzy right about now, with your nice working generator. But there are bad days coming. This site was set up with some strict rules. You my good man appear to have violated rule #1. You can expect some severe retribution from the founders, and perhaps an ugly visit from "guest". Keep a constant vigil for the towns people with pitchforks and burning torches.

Please remove your last post immediately. You are never allowed to post a solution to a problem posted here.

Glad to hear that it went well for you.

Hi, Offthegrid!

Great to know you're all set up and running again. Thanks for the info. What will you be doing about the cold propane?

Mark

Hey offthegrid,

Did you happen to ask him about the Low Oil Pressure switch thing?

Johnds

Hey John has your start problem gone away as the ambient temps moderated?

Or have you been able to get near your genset to install a bypass switch.

Yes, I have no problem starting and continuing to run above 15f.

No, I have not yet installed the lop bypass switch.

John

Hi all, I'm thinking of blanketing the propane tank (the lines are already buried). Not sure how safe I feel trying to keep the tank warm by adding heat of some kind. Maybe an electric blanket? I asked him about the low pressure switch and he said he'd never had/seen problems with it. I told him of the bypass discussion and such but he kind of just shook his head. ??? He did say that many problems come from having too much oil in the generator which then causes various seals to leak/blow and oil to get in everything, which has happened to us. The dip stick on my genny broke a while ago and I had a bungy cord holding it on tight (have since ordered a new one). Unfortunately, my husband's first thought whenever the genny crashed and burned was 'add oil' as that's pretty much the extent of his mechanical experience. It's taken a lot of training by me to get him to NOT add oil everything something happens with the genny! Even his buddies always want to just add oil. It got a bit ridiculous as I was constantly draining oil just to get the genny to run. Sadly, this did cause us some issues as I had oil blowing back up through seals into the air filter housing and the entire motor was often coated with oil. A couple of times I had to run it hot and wide open (no insulated sides on) just to burn off the oil and keep it from catching on fire. But I digress... Cheers, A :)

Good point! The small engine sizes used in these gensets ( under 15kW) are very sensitive to oil level. Being small there is a very limited volume contained inside the crankcase. It is much smaller than even a compact car engine. Unfortunately many folks acquire their "motor knowledge" from automotive experience and attempt to apply it indiscriminately.

Cold weather starts also mean a period of warm-up time during which some blow by is inevitable. If the crankcase is over filled, ther I a tendency to blow out any excess oil froth or vapor by any path available. This includes shaft seals, and the PVC hose. If the oil level is high enough for the lower end of the connecting rod to hit the oil surface, mechanical damage can result.

How is your hot water storage system powered? could you rout a hot water line around the propane storage tank, and back into the house. The hot water use would transfer some warmth to the propane storage tank. If freezing is a concern, you could do a small pump to circulate an antifreeze solution through a liquid to liquid cooler, and to an automotive heater core inside an enclosure around the propane storage tank. Transfer some of the stored heat from the house to the propane tank.

What about the electric battery blankets for cars?

Hi, thanks for the ideas. Our hot water is propane powered but it is very very far from the generator propane tank; opposite side of the house, across the yard, across the driveway, up the hill. With bedrock in between. One of the auto blankets might work; I'll look into that. Now that it's warmed up a bit, it's hard to even remember the panic of last month when I was trying to get everything working. Talk about reactive instead of proactive, eh? The genny is working fine so we forget about it. Will work on that attitude. Thanks again for everyone's input! Cheers, A :)

What about a solar charger for the 12 volt battery that is connected to the inverter that is connected to the battery warmer that is attached to the propane tank. WOW.

Bob - the perpetual motion forum is on another page. ........But seriously !!

Off grid homes only need a generator when the sun is blocked by clouds or the wind has not blown for a while.

In other words the alternative sources have already failed to provide energy and the battery bank has nearly gone flat. And that is why a genset is required to make up the missing energy.

The problem with Propane in northern locations has to do with the evaporation temp of propane. Every single mechanic up here that I have spoken to on the subject, look at me strangely when I ask them what they think of emergency power from a propane powered generator up here. They all know that propane does not volatize at the cold temps we routinely encounter up here. One old timer asked me if I had ever seen liquid propane. He told me at -35 below you can pour it like water and it's a pale blue in color. Gasoline engines will still start at much lower temperatures. So logically in cold northern locations a gasoline engine is actually better for emergency start in the cold winter when sun and wind has already failed.

Evidently this is a point the designers in southern locations are not aware of.

I think I would have an electric blanket or similar to cover a propane fuel tank and power the heater blanket with a gasoline engine. Propane is cheaper than gasoline so it does make sense iif I heated or cooked with propane. This emergency electric heating of the propane tank is only needed during extremely cold conditions.

My friend who lives near Dawson City tells me she starts her truck in late october and neve shuts it off until next april. If she did, then the engine would not start again till next summer. . . . of if she had it towed into town where she could get it into a heated garage. But then she also say they get closer to -50 or colder on some nights.

Hi Elnav, Thanks for explaining off-the-grid life more succinctly that I ever could! Things are crazy, will be in touch soon. Cheers, A :)

Thanks for the explanation.

Sorry to revive an old thread, but I could use some help.

I have a 2004 Onan Generator RS 12000 Model 12GRCA-422A running on propane. I'm getting an error code, 4 flashing red lights, so I would like to perform regular maintenance such as replacing air cleaner and oil filter. However, I was a bit shocked to discover the price of the replacement parts from Onan: Air Filter Part #184-0142 for $173 and Oil Filter Part #184-0141 for $55.35.

Onan customer service could not explain the exorbitant price and suggested I contact a Honda dealer or even an RV maintenance site. I can't locate a Honda engine number to even know what to ask Honda for. It's very annoying of Onan to charge such outrageous prices for basic parts when they go from Honda to Subaru engines. I don't think I would purchase their products again. Can anyone suggest another less-costly option for the air cleaner and oil filter?

Thanks

Not knowing where you are located, leaves me with providing an answer that should be useful in most of the U.S. where I am familiar. If you have the Onan part #s bring them with you to a GOOD auto parts store. Good stores will be able to cross a manufacturers part # over to the line that they carry. If that will not work, use Google. Good luck.