2002 searay won't start when warm

Macisking

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Oct 5, 2017
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6
I have a new too me 2002 searay 190 with 4.3efi
Boat starts perfect when cold and perfect when hot. But after running for a while then just stop and float for say an hour or so boat will not start. Have to let it sit till engine temp drops below 130 before it will start. Then it runs fine. It seem that if engine temp is below 150 but over 130 it will not start. Has anyone else had this problem? Any help would be great. Thanks
 

alldodge

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My first guess is vapor lock. When the engine compartment gets some heat soak happening after running for a while, the het builds up and causes the fuel to boil. The increased pressure creates a vapor pocket in the fuel system. When the motor is cranked over there is no fuel to run. If the motor cools back down it will start. It will start back when hot if it has not been shut off very long.

Merc has attempted to fix and says to make sure to run the blowers when idling after a good run for a while. Has even installed a boost pump and this has helped some. Open the engine hatch to help it cool down. The real fix is a rerouting of the return fuel line from going back to the filter, to return it back to the tank
 

scoflaw

Ensign
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Jun 2, 2010
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962
Have you tried advancing the throttle when cranking ? Probably the IAC valve if that works
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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welcome aboard.

Which seat arrangement / engine compartment config do you have on your 190? i have heard of issue with the small dog house and rear jump seat arrangement with vapor lock. are you running the blower constantly?

need pics of the boat..... just because we like pics
 

Macisking

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Oct 5, 2017
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So went out today ran for an hour stopped for 10 min and boat started fine ran for 30 min and stopped for an hour and wouldn't start. I used starting fluid and motor would fire and run as long as I sprayed starting fluid in carb but wouldn't stay running. Guess that rules out electric problems because there is spark so back to vapor lock as possible problem? Thoughts? Please and thankyou
 

Macisking

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Oct 5, 2017
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Also not sure if it matters but when I put fuel in boat once it's full I get lots of fuel shooting out of fuel port. Vent problem maybe?
 

QBhoy

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Mar 10, 2016
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8,286
Does this engine have the cool fuel system ? Vapour lock is a candidate.
 

Macisking

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Oct 5, 2017
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Not sure what a cool fuel system or RBI or moi motor is it's mercury 4.3 v6 efi. How do you fix a vapor lock?
 

alldodge

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I'm going to assume its a TBI, and as mentioned above the real fix is to run the return line back to the tank. This can be done at the fill hose. From what I'm reading you may not be handy with the do it your self stuff, but if you can find some one that is to help.

The pic below is for an MPI (Multi Port Injection) and I think you probably have TBI (Throttle Body Injection) and both would use cool fuel. The cool fuel module is on the port side of the motor below the motor mount.

Vapor Lock Fix.jpg
 

Macisking

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Oct 5, 2017
Messages
6
Alldodge thanks for info. Your correct rerouting fuel line is a bit above my ability. Looks like I'm headed to dealer. I'll pass your info along to them
Thanks again
 
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