Only starts with Muffs

[DKR]

I have an 1989 OMC Cobra 2.3L engine. Engine was overheating, so I started by putting in a new impeller and checking to see that the thermostat was opening and closing by boiling on stove, it was; I put thermostat back in, took the boat to the lake and it would not start. I brought it back to the house put the muffs on in the driveway and the engine turns over easily. What could be the issue for not starting in the lake but starting easily in the driveway?

 

[Don S]

Re: Only starts with Muffs

This has come up on different engines and different times and no one ever comes back with a real answer. Did have one guy say his trim sender wires were the cause, but that's impossible.
So who knows.
Some things to check.
Compression, point dwell, timing, carb adjustment. Any of which may cause your problem. It may sound ok to an untrained ear when hearing it run, but the setting could be so far off that it will run ok till you put a little exhaust back pressure on it. Then, it's a new ball game.

 

[Bondo]

Re: Only starts with Muffs

Ayuh,.... My WAGuess is,...
It ran dry once,+ the exhaust shutter got Burnt up,...
Now it's bouncing around in the down tube,...
When you back into the pond, it floats up,+ Blocks the exhaust,... Motor won't Start....

 

[Don S]

Re: Only starts with Muffs

Ayuh,.... My WAGuess is,...
It ran dry once,+ the exhaust shutter got Burnt up,...
Now it's bouncing around in the down tube,...
When you back into the pond, it floats up,+ Blocks the exhaust,... Motor won't Start....

I can see that happens when you open the trottle up and try for high speed, but not starting. Shoot, you could plug the exhaust bellows tight and it would start for a few seconds then die.
But to not even try to start, or maybe it does. We just never get the whole story of what it does.

 

[Bondo]

Re: Only starts with Muffs

We just never get the whole story of what it does.

Ayuh,.... Kinda hard to Hear,+ See over the internet,....

As an aside,..
I was once hired on the spot when I unscrewed,+ removed an O2 senor, allowing a car to start with a plugged solid cat....
Went from man on the street to Chief Mechanic with a single diagnosis....

 

[DKR]

Re: Only starts with Muffs

So any suggestions on correcting the issue?

 

[Bondo]

Re: Only starts with Muffs

So any suggestions on correcting the issue?

Ayuh,.... Start with a Full,+ Complete Diagnositic Tune Up....

 

[Don S]

Re: Only starts with Muffs

So any suggestions on correcting the issue?

Yes, check the basics, do you have spark when you back it in the water. Before you go to the water, do the checks I mentioned earlier. Post your results and let's see what is going on.
Like bondo said, we can't see, hear or touch your engine. All we can go on is your discription of the problem. And all that is is that it won't start when in the water.
Does it start and die, never fire, what. OVER load us with information about what happen. There is no EZ CURE button for any problem with a marine engine.

 

[coastalcruiser]

Re: Only starts with Muffs

dkr
When you took your boat to the lake is there any chance at all your remote control was in gear? it won't start if it was.

 

[DKR]

Re: Only starts with Muffs

Coastal Cruiser: Positive that it was not in gear when attempting to start in lake. It sputters and seems initially like it wants to start and even had it going momentarily but when I kept giving it more power it shut down and the more I attempt it the more the battery seems to run down. Hope this gives a better description of what is going on.

 

[QC]

Re: Only starts with Muffs

Not in gear ever right ^^^^ Only revved and sputtered in neutral?

 

[coastalcruiser]

Re: Only starts with Muffs

is the fuel tank level low?? if its not it may be that the angle of the ramp causing it suck air.
LOL my neighbor got me to tow his truck to level ground and it started right up!
just a thought.

 

[DKR]

Re: Only starts with Muffs

Fuel tank about half to 3/4 full! When I was checking the thermostat, there was a fair amount of water that drained out of the hoses that attached to the thermostat housing, is that natural? Or could that indicate a blockage somewhere? Just trying to problem solve based on steps I have already taken.

 

[CheapboatKev]

Re: Only starts with Muffs

Any chance of posting a video?
Both on the muffs as well as while soaking?


Have you taken it a local shop for an assesment?

 

[coastalcruiser]

Re: Only starts with Muffs

Bondo and Don are the experts here, believe bondo was talking about your exaust shutters. after you decribed the problem a bit more sounds like there might be something to it.

 

[DKR]

Re: Only starts with Muffs

Sorry novice here, when you refer to exhaust shutters are you referring to the exhaust high riser? Is taking the exhaust high riser a matter of removing 4 or so bolts?

 

[coastalcruiser]

Re: Only starts with Muffs

http://www.dougrussell.com/partscat...7,628,629,630,631,632,633,634,635,636,637,638
pn 0985749 3853864 SEAL AY,EXHAUST

 

[Don S]

Re: Only starts with Muffs

Trust me, those shutters are NOT your problem with getting it started in the water. It might not run at higher rpm, but a broken shutter will only block the exhaust AFTER the idle relief ports.

Go back and read the things I mentioned in post #2 on this thread.
This is not a one thing only problem. There could be a number of things , but you actually have to go out and check them.

 

[DKR]

Re: Only starts with Muffs

Haven't had a chance to get back to working on boat but plan to this week. As a novice can and how do I check the compression and point dwell? You also mentioned the timing and carb adjustment as possible reasons for not starting in water. Is there a step by step process to follow in narrowing these 4 things down? Sorry but not real knowledge about engines but I can follow directions!

 

[coastalcruiser]

Re: Only starts with Muffs

how do I check the compression

You need a compression tester

and point dwell

rpm/dwell/tach meter

timing

inductive timing light

carb adjustment

Need a manual for your engine, not sure if you can find it in the adults only sticky in this forum