Hard start when engine is hot.

[Razvanbuc]

Hello

I am sorry for asking this question again but unfortunately i'm still dealing with this issue. So far i've done the following: rebuild carb ( it was flooding with gas when engine off after running) , new fuel pump and water separating filter, cleaned battery cable connections, check plugs ( they are clean, the color is light brown and mechanic confirm they look ok ). Does anyone have other suggestion what else to check. I was thinking maybe the aligment is a bit of or the distributor is no working well. Thank you

 

[Silvertip]

Re: Hard start when engine is hot.

What are we working on? All we know is you have a boat with an engine that won't start when hot.

 

[Silvertip]

Re: Hard start when engine is hot.

What are we working on? All we know is you have a boat with an engine that won't start when hot. What is your hot engine starting procedure? If the answer is turn the key and crank until it starts, that's the wrong procedure.

 

[Razvanbuc]

Re: Hard start when engine is hot.

Sorry... I tought it is in my profile... The engine is a 2000 3.0L GM mecruiser

 

[Razvanbuc]

Re: Hard start when engine is hot.

Hey Guys... I have to bump this since i really need some suggestion from the pros here. Thank you.

 

[salty87]

Re: Hard start when engine is hot.

did you clean/tighten the ground terminal on the block too?

 

[PitchFork]

Re: Hard start when engine is hot.

Carb unit?

 

[Apollo75]

Re: Hard start when engine is hot.

I do not have a separate throttle lever so at the lake I pumped it about 6-times and it started and died --- then three more times and it started and died then three more times and it stayed running ---- someone commented it was a pump up boat !

I would check the compression when it is hot --- then see if it starts with a pump or two after sitting --- try these things and get back to us.

OFM

 

[Razvanbuc]

Re: Hard start when engine is hot.

Salty87 - No.... Just at the battery... Will do soon... it can not be it because after it starts while hot then i turn off then on right away , it starts fine.... it has to sit off for at least 5 minutes in order to show this problem

Apollo75 - Would the compersion be diferent when hot?

Thank you

 

[Apollo75]

Re: Hard start when engine is hot.

Yes, the compression could change quite a bit --- the oil is hot and thins, and the cylinder walls where the rings seal gets all the oil cleaned off by running.

(rarely) ---> valve adjustment is off and when warn things expand and this could be a problem.

Hard to say --- I would try with a little more fuel --- if it better -- good --- if worse there could be a leak down problem where some fuel is leaking into the manifold after sitting --- this flooding takes a lot of cranking to start --- mostly core plugs on Q-jets.

Let us know

OFM

 

[Razvanbuc]

Re: Hard start when engine is hot.

Apollo75 - Before the carb was rebuild by mechanic it was leaking gas while off on hot but that went away now. When it is completly cold it only needs 2 or 3 pumps and it starts with 1/4 crank. I'm buffled why it would need more fuel when hot( tried up to 6 with not luck). I'm thinkind the aligement could off by a bit??? Sometime when i turn it off i can hear the engine turn on more time withour spark??? Thank you.

 

[Apollo75]

Re: Hard start when engine is hot.

I am sorry I do not understand alignment being off --- unless --- the starter does not crank the engine over as fast when hot as when cold ? This could be a battery, charging problem, starter issue, timing, etc.,

So, you have tried with more fuel and no luck ---- I would guess there is excessive fuel getting into the manifold --- but, it is hard to see from here

The run-on is detonation --- engine cooling around heads, low octane fuel, carbon deposits, plugs too hot for your engine, anything in the combustion chamber that has rough edges could be hot enough to do this.

I am sorry I am not more help.


OFM

 

[riverrunt1971]

Re: Hard start when engine is hot.

sounds to me like engine timing has changed, maybe to advanced