Hi all, Got a quick question about my 2001 5.0 V8 Mercruiser engine.
I had it running for the first time this year and noticed the exhaust manifold risers were at different temperatures. One was cool and the other was fairly warm. Definitely not hot though (I can hold my hand on it no problem) I didn't think this was normal. I'm not getting any alarms and the temp gauge is reading ok.
Any help would be great! I don't want this to develop into a bigger issue, etc.
They typically are different but I use an IR temp sensor to check mine as the helm gauge only shows the engine temp not the exhaust. 100F - 125F is good, over 140F time to clean or replace.
Thanks for the reply. Somebody mentioned to me about the raw water impeller and that it should be replaced every couple of years, so could be a circulation problem. I'll check that over the weekend.
When is the last time the manifolds, risers and elbows were replaced?? These need to be replaced every 5 years or so if running in saltwater. Are you seeing engine tempts creeping up when running above 4,000 rpm?
Boat has only ever been used in fresh water. Also looks like the impeller is in the drive on mine (alpha drive). So it'll be a job for the next time I pull it out.
Boat has only ever been used in fresh water. Also looks like the impeller is in the drive on mine (alpha drive). So it'll be a job for the next time I pull it out.
Yes the impeller is in the drive on Alphas. If you have any doubt pull the boat now else risk overheating and damaging the engine.
V8 exhaust temp difference
Linear Mode
