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1977 evinrude 70hp flywheel hard to turn

J

jffield2002

New member
So I bought this engine from someone who had it in storage since last fall. I put a new starter on it and I have a new battery on it also. When I go to turn over the engine the flywheel turns slow. Tried to turn it by hand it moves but is hard to turn. I took out spark plugs and the starter turns it over perfectly fine as it should. Not sure what is causing this to happen please helpppppp!!!!!
 
Check oil in the lower unit.----Inspect battery cables.----Load test the new battery.-----Perhaps try with booster cables direct to the starter to eliminate wiring on the boat / motor.
 
racerone said:
Check oil in the lower unit.----Inspect battery cables.----Load test the new battery.-----Perhaps try with booster cables direct to the starter to eliminate wiring on the boat / motor.
Click to expand...

Ok so I checked all of that everything seems fine. Used a booster and had the same problem with the plugs in. I pulled one of the plugs out and it spun around fine
 
Time to do some basic tests. Check compression (if you can). Do some voltage drop tests on the cables. I assume you replaced the starter because the old one wouldn't crank it either?
 
To test the electric starter..... Have a good known fully charged battery and good known jumper cables. Now, with those jumper cables, apply them directly to the electric starter. If the starter cranks the engine over normally (with all s/plugs installed)... the electric starter is okay.

With your present setup whereas the engine either cranks over slowly or doesn't crank at all (and you know the starter is okay)... the problem is normally a loose cable or tight but dirty cables (voltage drop). In either case, disconnect and clean all cable and wiring associated with the starter circuit, including the battery terminals and the ground cable at the powerhead.

Clean the terminal ends thoroughly along with the component they attach to, then tighten securely with a wrench or pliers... not your fingers if wing nuts are encountered.
 
joereeves said:
To test the electric starter..... Have a good known fully charged battery and good known jumper cables. Now, with those jumper cables, apply them directly to the electric starter. If the starter cranks the engine over normally (with all s/plugs installed)... the electric starter is okay.

With your present setup whereas the engine either cranks over slowly or doesn't crank at all (and you know the starter is okay)... the problem is normally a loose cable or tight but dirty cables (voltage drop). In either case, disconnect and clean all cable and wiring associated with the starter circuit, including the battery terminals and the ground cable at the powerhead.

Clean the terminal ends thoroughly along with the component they attach to, then tighten securely with a wrench or pliers... not your fingers if wing nuts are encountered.
Click to expand...

Thanks for all the info! So I found out that top piston is messed up. So I guess I lost on this one I'm not sure if it is even worth repairing at this point.....
 
jffield2002 said:
Thanks for all the info! So I found out that top piston is messed up. So I guess I lost on this one I'm not sure if it is even worth repairing at this point.....
Click to expand...

Ah.... Bummer! But as with any 42 year old engine, this happens. Hopefully you got it for a song, so to speak and you can recoup your loss by parting it out.
 
What do you mean by "messed up"? Can you send us a picture? Don't forget to reduce file size.
 
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