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carl lewis
04-27-2009, 01:05 PM
Hi guy's,

My self being more of a wood and boat guy than a motor guy I need some advice.

My cousin has an older mid '70's 85 4 cyl. OMC that he (we) use about 4 days a year to go shrimping with, so yesterday I was helping him with the little motors (carb rebuild new points gear case oil ect.)

and we started to see if the 85 would run. I checked spark and fuel, all connections free of corrosion ect. doing the basic stuff plus a new deep cycle/ starting marine battery just so the basics were covered.

so heres the deal I can only get it to crank over one revolution ( thats all 4 cyl.) before the starter (bendix) stopped. I can do this time and time again ( not wanting to of course no need to fry the starter) but since we have spark, compression, fuel could the starter be taking a crap and not having enough in it to make this thing turn over like it should be doing? most likely this is the original starter, at least it sure looks like it .

any way like I said I'm ok with the smaller motors and the boat building/repair part of things but these old 4 cul things get me a bit lost at times.

thanks in advance for any suggestions.

Carl

Bunker Hill
04-27-2009, 02:37 PM
What if you were pull the plugs and let her spin over for about 20 revs? Might loosen her up a bit, or if the starter is fried, it simply wont turn over
Just a couple of thoughts

Good Luck!!

Bunker

carl lewis
04-27-2009, 03:15 PM
Bunker,
tried that as well to check compression, but it did not spin over like a jack rabbit but it still did spin as long as I wanted it to.

Carl

Dan M
04-27-2009, 05:45 PM
About 30 years ago, had a Chrysler that would start to crank, it would fire once and disengage the starter when it fired. Ended up being the CD box.:rolleyes:

Dan

Powerabout
04-27-2009, 05:46 PM
what year?

or how about the following
did it have a set of points under the flywheel?
does the exhaust exit thru hub?
does it have power tilt?

carl lewis
04-27-2009, 06:39 PM
what year?

or how about the following
did it have a set of points under the flywheel?
does the exhaust exit thru hub?
does it have power tilt?

sorry I dont know the year
no pionts early stator type

dont know about the exhaust buy my guess would not be through the hub

power tilt works great

mercguy
04-27-2009, 06:53 PM
sorry I dont know the year
no pionts early stator type

dont know about the exhaust buy my guess would not be through the hub

power tilt works great


:eek::eek::eek::eek:

Skoontz
04-27-2009, 08:42 PM
Loose the deep cycle and hook up an Optima with 500CCA. You should be able to rope start it with one pull, after all it's an OMC.

Also, check the connection between the starter and engine block as well as all grounds. There should be a ground strap from the starter top to the engine block, they used to be a flat piece of weaved wire. If that is trashed, take a hunk of 10 guage multi strand and some loop ends, soldered is best but you can crimp them if you like, just use some goober von schlopen to keep them from corroding.

If you have a starter load tester, might want to check it just for yuckadoodles.

Mid 70's would be through hub exhaust.

looseunit225
04-28-2009, 02:37 PM
i would say the starter sounds like she is starting to poll out!

have a sniff of the starter see if it smells burnt although it may not smell burnt could still be toasted!

when you had the plugs out did you put a plug in a lead to see if it was sparking?

JohnsonM50
04-28-2009, 02:50 PM
If its 70s its most likely CDI type. The starters can get cruddy inside w/o seein it from the out. Check that its not too tight to the flywheel, if so it could bind. A shim can fix it if so. Its likely bad tho. These are not impossible to rope if you want to see it run before $pending on a starter. Good Luck