4 cylinder Mercruiser stalling at low RPM and heating up

av8tor3sp

Cadet
Joined
Mar 4, 2009
Messages
8
Hi all,

I just bought a 1980 galaxie with a 4 cylinder mercruiser, I took it to the lake for the first time and discovered a couple of problems, I am hoping that with the limited amount of information I can give hopefully I can get pointed in the right direction on what to do.

Number 1: After getting the engine started and heading out into open water, I went to throttle up and right around 2000 rpm, the engine stalled. I restarted and the engine did just about the same thing, right around 2000 it stalled. The next round I brought the engine up to around 1800 let it sit run for a few seconds then pushed the engine past 2000 and it ran fine all the way to wide open throttle. Could it possibly be something with the carb that isnt letting the engine accelerate normally?

Number 2: After a few high speed passes on the lake, we decided to troll around the lake, after about 5 mins, I noticed that the engine was getting really really hot, I removed the engine cover and there was smoke or steam coming from the top of the engine. We let the engine sit, then restarted to try and get back to the marina, while underway I noticed that with the engine at high rpm it doesnt seem to overheat, the temp is still pretty hot, but it doesnt get to the point of smoke or steam coming from the engine, could this be the water pump?

I hope this wasnt too much for one post... Thanks for any help you can offer!
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: 4 cylinder Mercruiser stalling at low RPM and heating up

1. Probably needs a new raw water pump impeller, vanes on old impeller are probably permanently bent over from old age.
2. Carb accelerator pump may be the problem, sounds like a carb rebuild is in order. Probably wouldn't hurt to do a complete tuneup and eval of the engine and drive/ujoints/gimbal area. since the boat is new to you.
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
71,258
Re: 4 cylinder Mercruiser stalling at low RPM and heating up

Ayuh,...

#1 sounds like Crap in the Fuel System...
It could be anything from the gas tank Vent to the Carb.....

#2 sounds like the Impeller is Shot,+ needs Replacing....
 
Top