Starter vs. "partially seized"

Hello all. Thanks for making this forum worthwhile. I would really appreciate your ideas on my '82 850 Merc problem.

I bought the boat not running recently. The seller said it had electrical problems and that it ran last year. It turned over by hand and the price was very good so I bought it.

I started by taking the shroud off and pulled the cables off the starter lugs and hit them with a fresh battery. The starter struggles with turning the motor over. I does maybe 1/3 turn of the flywheel. So I replace the starter with the same result. I can turn the flywheel over by hand but it isn't easy. It just feels like high compression. I try some pulls with the rope. I don't do any better than the starter. It is very difficult but how hard should it be to turn an 85 HP 4 cylinder motor with a rope?

I need to explain at this point that this is starter number 50 66015. This is a common starter on Mercs but this part number has been superceeded a few times. It is possible I am told to have a starter than it longer than mine with 11 teeth. Mine is 8 teeth and the starter fits the mount right where it should. The starter that was on the motor was replaced by the prior owner so it may not be right. I'm wondering if perhaps I should have the 11 teeth version. The flywheel and the starter don't seem to mesh ideally although I can't tell if this is because this is so hard to turn over.

Anyway I have some questions for any salty Merc vets out there. Should I really be able to start this thing with a rope. Seems like the thing to do at this point is to take the plugs out and lube the cylinders and see if she loosens up. Anybody had similar difficulties with getting a replacement starter or similar problems? Is there such a thing as "partially seized." I read that perusing the forum. I always though high compression is a good thing. Thanks for reading my post. I would appreciate your experience.

washingtonmerc

Re: Starter vs. "partially seized"

i can only tell you what happend to me.i have a 650 (65hp) 4cly.and it sat for ten years was locked up. i freeed it up had fuel spark compression but acted like the compression was keeping it from turning over.pulled starter apart and found the brushes rusted up cleaned every thing and put it back. starter spun it over about 4times faster and VEROOM away she went.so i would def check the starter.a further note starter worked better when the plugs where out and no load on it.i hope this can be of some help.

Re: Starter vs. "partially seized"

WM, Remove the spark plugs. The motor should turn over smooth w/o binding. There will be some resistance when the pistons compress the crankcase air/fuel, but nt a lot.

Look up your serial number at maxrules.com to get the year. I had thought they dropped the 850 designation in the late seventies.

Re: Starter vs. "partially seized"

Chris 1956 you are right...Motor looks to be a 1977.

I'm responding here for the sake of other with a similar problem.

The problem is that I was jumping to the lugs on the starter with a bad jumper cable.

This motor has a lot of compression but when you get a charged battery to a decent starter she turns over like a champ. I don't think I could start this thing with a rope. I would like to see a 300# tackle even try.

Thanks to those that responded.