Four-Stroke Outboard - Motor Storage Problems

capnbob,

Surely, if it's a new motor, you have a waranty coverage with it.

All that aside; due to the amount of information you gave us (practically none) it will be pretty hard to make a diagnosis.

Let's start, however, with a few basics.

1) Have you ascertained that there actually is fuel in it? Maybe it leaked during storage or someone helped themselves to it.

2) Have you checked any pertenent switches (everything in the 'on' position)?

3) Have you checked for spark at the plug? Pull the plug and check for fouling?

4) Does it have a manual choke (if carburated) and if so, did you have it in the start position?

5) During storage, was it kept in an upright position? Perhaps the pickup tube is not sitting in the fuel.

My GranDad used to say; "Boy, there's only 2 reasons a motor won't start - No fuel or no fire."

Hope that helps.

The third one is compression.

Only these three things are needed.

Compression, fuel, spark.

On a Diesel its just two, compression and fuel (injection).

try again. diesels burn fuel too.

as for the other.....compression loads the fuel - therefore no compression = no fuel.

back to 2?

High Guru,

What is your answer supposed to mean?

Did I not say a diesel needs compression and fuel? Hmm.

What do you mean by: "Compression loads the fuel" ?

As far as I know, compression happens when the piston moves up compressing the air inside it, and fuel is injected under high pressure by a separate fuel pump or injector pump. The compression ratio has to be high enough to heat the air inside the cylinder above the ignition temperature of the Diesel fuel. The diesel fuel will then burn when injected into the hot air.

Yes, yes. Apologies typing too quickly - thanks for the correction Ass.

The compression stroke is just that- compression; as we all know, of the fuel air mix from the opposing stroke.

You were making the point that there are 3 reasons an engine will not start and feel that there are only two. You also suggested that no spark was needed presumably because of the nature of a diesel engines design. However this is not entirely true - thus the glow plug which is required for a diesel to start.

The reference to my GrandDad was a bit tongue in cheek. He had a great way of simplifying things - bringing problems at once to the fundamental starting point (no pun intended). He was very wise.

I am not 100% certain, but I do not believe that the Mercury/Mariner 9.9 hp motor is a diesel any way.

Again thanks for the correction. I am embarrassed at such carelessness on my part.

Wow. Two consecutive typing errors-

_{Yes, yes. Apologies typing too quickly - thanks for the correction Ass.}

Should read-

Yes, yes. Apologies typing too quickly - thanks for the correction Assc.

Apologies again,

Charles

Sorry to step into the middle of this, but, if no oxygen gets into the cylinder, no amount of compression will cause flame.

Also in 4 strokes, the intake stroke loads the fuel. This has a carb, not injectors.

What's an "outboar motor"???

Happy Boating

LL

Something that I have found lately is phase separation of the ethanol blend fuels that are being sold today. I own a shop and I do alot of work on smaller engines as well as larger engines we have found that the fuel will separate in approx. 3 to 3 1/2 weeks. This is caused by the inherent characteristic that ethanol will draw moisture from the atmosphere and prefers to bond to the water molecules and separate from the gasoline. When this happens then you are left with two separate components in the tank the lower layer will be the water & ethanol mixture and the upper layer will be gasoline but will only have an octane rating in the 70 to 75 range. Neither of these will run the engine. As of now all the research that I have been able to find are perform myself there is no additives that will stop phase separation of the fuel. What you can do is drain all of the fuel out of the tank and make sure that you drain the float bowls and get fresh fuel from a station that sells a lot of gasoline as they will have fresher fuel in there tanks. Also use nothing but premium fuel as there seems to be a much less occurrence of this at least in Texas because premium does not have the ethanol added to it. When you buy premium for your small engines pump the first gallon are so into your truck if you are getting gas from a one hose pump as the first gallon will be the fuel that the previous customer bought. The reason that it does not separate in the storage tanks at the refinery is the ethanol is added to the gas when it is put in the truck for delivery to the retailer as they are aware of the phase seperation problem and know that they are only able to keep it blended for a short period of time. Figures that I have been able to find is that 100 gallons of 10% ethanol blend fuel will draw about 1 gallon of water from the atmosphere in a 24 hour period.

Hope this helps.

I'm with Jim on this one. Blended fuels agggghhhh, not worth the problem. Less value for money than straight fuel. Ethonal has about 1/3 the power output of Petrol. Dont beleive me, check out the calouries of Ethonal against Petrol.

Presumably it's a carbureted motor with a means to close off or disconnect the fuel supply to the motor. Before shutting the motor down, disconnect the fuel supply and allow the motor to run until it dies from fuel starvation. That should help prevent gumming and other problems during storage.

Even though the gas stabilizer helps keep the gas from going stale. It doesn't all ways keep it from gumming up the system over the winter. But 2 to 3 weeks isn't a winter storage duration. So I would say you have another problem with the motor. In that it is new I would approach it as a warranty issue with the retailer. Have them fix or replace it.

2 to 3 weeks is sometimes the duration between my fishing trips. Sure wouldn't want to deal with it not starting every time I got the boat in the water. Or spend the extra time in prep the night before making sure it would start.

Years ago I had a Yamaha motor cycle with a similar problem, let it sit for a couple weeks and you needed starter fluid to get it to start along with a large stock of expletives. I finally figured out that the "problem" was a vacuum operated fuel petcock. No fire meant that the petcock would not open so no fuel. Once I figured that out I was good to go, just place the petcock in the manual open position and it would fire right up. I finally realized that it was covered in of all places the owners manual (Who'd a thunk it?). Read the manual!