89 Baja Force 7.4 L 454 v8 engine overheating

I just took my 89 baja force with a merc 7.4 L out of winter storage 3 weeks ago and noticed I was running HOT 180 to be exact. I normally run 160. I went right at the impella and replaced it though it looked fine. Then went toward the tstat took it out and ran the engine without one. She ran 110-120 maxing out at 140. I reinstalled a new thermostat started her up and the temp gauge raced to 200. Any suggestions on whats going on. Right now I removed the thermostat to make it back to the dock. Any suggestions would be appreciated

welcome to the forum.

would have probably been better to post this in the mercruiser section.

Do you have an IR temp gun? Good investment if you don't.

Guessing this is a raw water cooling system? You want to get the t-stat back in as running the engine that cold will kill it in a short period of time.

When was the last time the elbows were changed?

The odd thing is, if I hold the trim button, say down, with the trim all the way down, so it is maxed out, the enging smooths out and gains 500rpm. As soon as I let the button go, the miss comes back and engine slows down. I went thru most of the electrical syst. trying to find a short. Can't pin down a problem.
What is the correct initial timing setting, and any ideas at all on the miss, running issue, and why would putting a load on the trim pump make the engine run fine??

angelblue15 said:

The odd thing is, if I hold the trim button, say down, with the trim all the way down, so it is maxed out, the enging smooths out and gains 500rpm. As soon as I let the button go, the miss comes back and engine slows down. I went thru most of the electrical syst. trying to find a short. Can't pin down a problem.
What is the correct initial timing setting, and any ideas at all on the miss, running issue, and why would putting a load on the trim pump make the engine run fine??

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Ayuh,.... My 1st Guess would be Bad motor Grounds,....

Clean the battery terminals to shiny clean metal, 'n try it....
'n don't forget, the wires have Two(2) ends,...