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1970 Evinrude 6 hp Compression question.

6tring

Contributing Member
Happy New year to all.

What would be a good compression reading for a 1970 evinrude 6 hp? I am getting 60 psi on both cylinders. The motor has not been run for about six years I have been told. Should the cylinders be soaked with a lube of a sort incase the rings are sticky? Any help here would be appreciated.

Thanks Don
 
Not too bad.-----But if the head gasket is original it was a poor design.-----The new replacement ( Sierra ) is better made.------I suggest you replace it.-----Install a new water pump impeller now.-----And if ignition coils are original they will need to be replaced as well.
 
Great advice, Racer. I know both you and I really appreciate these simple and reliable little motors. If it still has the original head gasket, it certainly should be replaced. The hardshell green coils tend to crack, then will develop a little hole and jump to ground. This will often be the stator plate, or it can be the coils' steel laminates as well. 60 is not bad, but I put little faith in some gauges out there.
 
Thanks fellows for your great advice. Looking into coil replacement I see that their is a coil stator spacer ring. Is their a way around this without purchasing this tool? {$100.00} Or is this tool a must have tool for the job?
 
Not a must have .------Were the old coils all cracked ?----Set the coils using the mounting bosses.------leroysramblings-----Is a site with all the info for you.-----Don't forget to check thermostat.----I usually find them stuck open or missing altogether.
 
Not a must have .------Were the old coils all cracked ?----Set the coils using the mounting bosses.------leroysramblings-----Is a site with all the info for you.-----Don't forget to check thermostat.----I usually find them stuck open or missing altogether.

Have not opened the engine yet. If the coils do not appear to be cracked do you think they would be good for further service after testing with ohm meter? Or at this point for preventive measure them replace them along with head gasket, thermostat and pump Impellor.
 
If the coils show no visible cracking, they are probably okay. On rare occasions, I have found they can arc internally, interrupting or diminishing spark. These coils may even pass the ohms test. Yes, agree with Racer, that adjusting ring is not needed when careful consideration is used to line up the coils' laminate surface properly to the back or inner edge of the chamfer on top of it's mounting posts. Here is what happens when coils crack.
 

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??----Need to stop and inspect stuff before rushing out and ordering new stuff.-----On most of these motors the coils have already been replaced.----But not always , I am just finishing a 59 model 5.5 Evinrude had new points and condensers but original coils.----One had burned through to the magplate.-----Post pictures when flywheel is off.----Be able to tell in one second if they are original still.
 
These are great great motors. Here is a 1973. Now THATS a LONG JOHNSON, brother. Gotta get it fixed up and listed on eBay. Should bring 8 to 9 hundred.
 

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Damn.....I'm getting pretty old looking, must just be a bad picture. Wife wanted a long long Johnson for her boat on the Philippines. Never saw a 29" before. It's so cold here, I brought it into the basement to work on it. I'll probably sell it on eBay and bring a 20" 6 to the Philippines. Gasoline there is about 5 bucks a gallon, but very little ethanol used. Most vehicles are diesel fuel powered. Most boats are inboards with tiny single cylinder Honda motors. However they don't troll down good for fishing.
 
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Not a must have .------Were the old coils all cracked ?----Set the coils using the mounting bosses.------leroysramblings-----Is a site with all the info for you.-----Don't forget to check thermostat.----I usually find them stuck open or missing altogether.

If you are popping open the thermostat housing be sure to have a replacement gasket on hand. I was futsing around with my nephew's 6hp and made the mistake of taking it off and the thing then sprayed all over the engine when re-installed.
 
If you are popping open the thermostat housing be sure to have a replacement gasket on hand. I was futsing around with my nephew's 6hp and made the mistake of taking it off and the thing then sprayed all over the engine when re-installed.

Thermo and gasket are on the to get list.
 
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