mercrusier 165 4 cylinder overheating

[broush69]

long story short. I removed the head out of the engine because of a broken spark plug. got everything back together. put in fluids again. then i took the boat out yesterday it seemed to run fine however i started to notice that the temp gauge was risiing. I wasnt sure if it was a bad gauge or if the engine was overheating so i kept driving it alittle longer then i started to notice smoke coming from the engine so i shut off the engine. after about 30 minutes i opened up the expansion tank for the anti-freeze and realized it was completely empty but it didnt leak. i saw no trace of anti-freeze in the bottom of the engine. anyone have similar issue with overheating? I'm assuming i didnt put in much anti-freeze but was curious if i should be watching around for somethign else?

 

[Don S]

Re: mercrusier 165 4 cylinder overheating

Pressure test the heat exchanger. The antifreeze may have been pushed out into the raw water side.

 

[stonyloam]

Re: mercrusier 165 4 cylinder overheating

long story short. I removed the head out of the engine because of a broken spark plug.

Did you use an OEM Mercruiser head gasket? Did you bring the engine up to temperature, then retorque the head bolts before running it hard? Better do a compression check and cooling system pressure test. Borrow the tools from Autozone.

 

[broush69]

Re: mercrusier 165 4 cylinder overheating

i did replace all gaskets but didnt retourque head bolts after running the engine for awhile. Everything was fine prior to me removing the head. not really an engine guy so i dont really know how to check compression and cooling system pressure.

 

[stonyloam]

Re: mercrusier 165 4 cylinder overheating

According to the mercruiser manual, if you do not retorque, the gasket can fail. The tools come with instructions, and the tests are pretty easy. Go to Autozone and ask to borrow a compression tester and a cooling system pressure check kit. You need a manual here: http://boatinfo.no/lib/library.html# Either Mercruiser manual #3, or #8 depending on the year/serial number of your engine.