4.3 hard to start when warm

[eastont]

I just had a valve job done on my port 4.3 merc. Now the issue is, it starts fine when it's cold, but when it's warm it's not easy.

Lats weekend we were out and I stopped to take on more fuel. Then when I tried to start the engine it wouldn't go. It took me about 1/2 hour before it fired up.
Any one have an answer?

 

[sethjon]

Re: 4.3 hard to start when warm

Does it turn over when warm?

 

[eastont]

Re: 4.3 hard to start when warm

Yes it does turn over, but it won't fire up. I tried pushing the throttle wide open, and still no life, then after sitting for about 15-20 minutes I turned the key and it started.
When I got back to the dock I tried to simulate the same situation and it fired right up. The mechanic is scratching his head. He can't find anything wrong.

We're going out for a few days this Sunday with our 5 years old grand daughter, so I hope I have no problems.

 

[jagilbert]

Re: 4.3 hard to start when warm

I'm no expert

Check that automatic choke is not closed when the problem occurs.

If the valves were incorrectly adjusted (i.e. set when the engine was cold) then the valves might not close all the way when hot. This would result in loss of power and fry the valves as exhaust gas leaks past not-quite-closed valves.

Just ideas. Hopefully someone with more experience will chime in.

Good Luck,