impeller ? on a 1975 OMC sterndrive

[supercab78]

I have a 190hp 1975 OMC sterndrive. I put in a new impeller pump when I replaced the shafts in the intermediate housing (rusted) about a 1 year ago. Put about 50 hours on it, on our last trip out the boat overheated big time it cracked one exhaust manifold. I tear it apart to find that the bronze collar on the impeller was freely spinning inside the rubber impeller. Has anyone seen anything like this happen?

 

[KaGee]

Re: impeller ? on a 1975 OMC sterndrive

It has been reported here. It's not common, but has happened.<br /><br />Wow, sorry to hear about the manifold... that's gotta hurt. Why did you run it so long??

 

[supercab78]

Re: impeller ? on a 1975 OMC sterndrive

My temp gauge was reading about 195 degree, which is 50 more than it usually runs. So I thought I would idle back to the boat ramp. It was maintaining that temp but we started to smell a plastic like oder. We thought it was someones campfire. Turned out it was the engine smoking and crackling. The boiling of water in the engine. At this point I realized the temp gauge was not be reading accerately. It never went past 195. I truely expect to have more problems than one cracked manifold because after it cooled I opened the block drains, bone dry. Like cracked cylinder heads. But compressions checked at about 120 on all 8 cylinders. I had it running with a hose hooked up for about 30 minutes and all I could find was that one manifold leaking. I quess I'll put it back together and see if other problems show up later.Hopefuuly those 351 windsors are tough engines.