OMC 3.0 liter, can't solve this problem

[tic]

I've posted about this before but the problem is still present.. 1988 fourwinns 160 freedom with OMC 3.0 liter engine/outdrive.. When boat is launched and first started, water temp guage goes up very fast to over 200 degrees. I shut down and remove inlet hose to T-stat housing and start engine (after cool down) water is flowing freely from the hose... re-connect and boat runs in normal temp range after that..Another thing I've done is run the engine at higher rpm for a few seconds and sometimes that works to lower the temp in a hurry too. again, this happens ONLY on the first start of the day.. New impeller kit installed, new T-stat installed, system flushed etc. etc.... It seems as though the system won't prime properly when first started on the lake.. BTW,after this initial overheating problem, the problem does not return for the rest of the day after numerous shutdowns and restarts. I can't duplicate the problem running the engine on the muffs.I think the force of water from the garden hose is priming the system. Outdrive was pulled and checked by marine mechanic, he replaced two rubber seals but the old ones didn't look worn or cracked in any way. Thoughts? ideas?. Engine has a checkered past.. Was not winterized and two cracks in the block have been fixed, one by a welder and one I did with JBWeld.. No water in oil and a dry bilge all the time after the repairs.

 

[tic]

Re: OMC 3.0 liter, can't solve this problem

bump

 

[THE BEEF]

Re: OMC 3.0 liter, can't solve this problem

Tic
Try installing a clear inlet hose to the thermostat housing, you can get it at a hardware store and see what is happening. It might be air locking with exhaust gases. At least you can see if you have good water flow.
It's a cheap way to find out whats going on.
Beef

 

[kueper]

Re: OMC 3.0 liter, can't solve this problem

I have a 1994 freedom with an omc cobra 3.0HO. I had a similar problem where the motor would intermitantly stop bringing in water, even with a new impeller. Turned out that the impeller was not the right size. Some parts book out there has the wrong size for the omc 3.0. I went through three before I got it sorted out. My motor has a seawater pump on the engine and the impeller goes in it instead of the outdrive. If yours has one check the size of the housing where the impeller goes to make sure theres a snug fit.