Mercruiser 5.7L - Stalling at about 2.500-3.000 RPM

[Rutto]

Dear All,
some days ago in the first test I had for the new engine I experienced a problem with it dying when increasing throttle (This Topic).
I finally replaced the electric fuel pump and Sunday I had a test trip, the engine now do not die, but it stall at about 2.500/3.000 rpm.

Please look at the video:

Can it be a timing/anticipation issue ? It was done with the laser gun but I cannot guarantee the after that it has not been touched...

Or can it be still a missing fuel issue ?

Any reccomandation ?

Thank you !!!

 

[Rutto]

Re: Mercruiser 5.7L - Stalling at about 2.500-3.000 RPM

And here is a second video:

 

[NHGuy]

Re: Mercruiser 5.7L - Stalling at about 2.500-3.000 RPM

From your other thread.
"Timing has been checked with the laser gun in front of me but then another mechanic touched my engine and I think he touched the distributor without using the timing laser gun. This happened prior my first test.
Carburetor has never been check-up since I bought this boat 2 years ago."

Timing and carburetor are the things to check next. Timing could easily be the problem. Verify that it is at 8 degrees BTDC (Before top dead center).
If the timing needs to be reset do it and go for a ride.
If it doesn't get better, or if it's already correct, come back and post. Good luck!

 

[Maclin]

Re: Mercruiser 5.7L - Stalling at about 2.500-3.000 RPM

Sounds like it is missing out on one or more cylinders to me. You said new engine, was compression checked?

Valve lash, if not correct, shows up at about that rpm.

Does it have electronic ignition? or Points type distributor? If points, and gap/dwell is not correct then that is abou tthe rpm that can show up.

 

[Rutto]

Re: Mercruiser 5.7L - Stalling at about 2.500-3.000 RPM

Hey, just discovered that my new block number is 10054724 and found out this discussion, same block and exactly same issue ! Exactly the same ! So for my understanding it seems to be a carburetor issue wich match with the fact that replacing fuel pump improved the situation.

http://forums.iboats.com/mercruiser...rts-mercruiser-5-7l-no-power-long-404384.html

What do you think ?

 

[Rutto]

Re: Mercruiser 5.7L - Stalling at about 2.500-3.000 RPM

How can I check if my intake manifold and my carburetor are compatible with my block ?

 

[Rutto]

Re: Mercruiser 5.7L - Stalling at about 2.500-3.000 RPM

FIXED ! It was the carburetor clogged !

 

[GA_Boater]

Hi everyone I'm new to the forum and I have the same problem on my 1989 regal ambassador 5.7L 250HP mercuiser .after 15 min of going @2800-3000rpm engine starts to stall. As what you guys mention here in the furom I've rebuild the carburetor and found out that the needle have been worn out . Then today I went out to test the boat and still doing the same thing so I adjust the timing at 8degree Btdc and still same would it be the fuel pump? Need help pls. Thank you

Read the Help Tip on top of the page and then start your own topic. Members don't often look at 2 year old topics.

 

[Tom3068]

I have a 1992 Four Winns. Has a 351 with Holley carb. It starts and idles great, but stalls in the water at WOT. I already rebuilt carb and replaced fuel filter and it still does it. Any ideas?