96 johnson 2hp compression

T

taisho

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I am down in Mexico and I have a 2hp Johnson. The power pack went south and I had one shipped down. After replacing it ran well for about 5 mintes then would not start. Checked spark nand it is good. Took it to a local mechanico and he said the compression was no good (60lbs). Should the engine fire on that compression? Thanks
 
fireman57

fireman57

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Re: 96 johnson 2hp compression

If it ran well then your compression is good enough. You want to make sure they are withing 10% of each other. If you have good spark then it is probably a fuel issue. Try squirting some premix in the cylinder and see if it fires.
 
W

Whoopbass

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Re: 96 johnson 2hp compression

60 lbs isn't that low for a 2hp. I think around 70lbs is average for those little guys so compression is not the problem and besides it was running fine before the power pack went down.

Make sure your fuel petcock is turned down and the air vent on your fuel cap is open.
 
JustJason

JustJason

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Re: 96 johnson 2hp compression

and check your voltage into the pack... if it's overvolting you'll eat packs left and right.
 
T

taisho

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Re: 96 johnson 2hp compression

How do I check Voltage and what is a proper reading? Ihave a good multimeter. thanks
 
JustJason

JustJason

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Re: 96 johnson 2hp compression

Do you have a DVA (direct voltage adaptor) for your multimeter? What meter do you have?
 
T

taisho

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Re: 96 johnson 2hp compression

Its a craftsman digital clamp meter but no dva
 
JB

JB

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Re: 96 johnson 2hp compression

WHOA!! Taisho said he checked spark and it is good. Let's not try to fix what aint broke.

I agree that 60psi is just fine for a rope start, single cylinder engine.

It ought to start and run just fine.

Taisho, go to the Top Secret file at the top of this Forum and do the "Why won't it start" article.

Let us know what you find.

Good luck. :)
 
fireman57

fireman57

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Re: 96 johnson 2hp compression

JB, thanks, it's been a while since I have been on here and I forgot about the threads that are there to answer a lot of these questions. As I said on DC I'm real glad that you are still around at the hideout.
 
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