96 evinrude 112 spl stalls

racerone

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My compression tester would show about 120 PSI on one of those motors !
 

tkdunn

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My compression tester would show about 120 PSI on one of those motors !

I had gotten a loaner tester from AutoZone. Perhaps it wasn't accurate? It's entirely possible I did the test incorrectly. How long should I have let the motor idle before checking the compression?

I will purchase a tester and retest.

Just want to verify the steps

Warm the engine, remove all plugs and wires, then test correct?

Does position of the throttle matter?
 

ondarvr

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It's very common for compression gauges to read differently, sometimes there's a significant difference, so having the cylinders close means there's a better chance of it being fine.

Warm or cold and throttle position haven't made that much of a difference in my teasing, and I've checked my results in every combination to see if it did. Best bet is to just do it the same every time.
 

racerone

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I always test motors cold.---People say that " throttle plates must be open "----But if you understand these motors than you would agree that the throttle position DOES NOT matter.
 

tkdunn

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I always test motors cold.---People say that " throttle plates must be open "----But if you understand these motors than you would agree that the throttle position DOES NOT matter.

What compression tester do you use? The one from AutoZone was OEM brand. I'm sure it has probably been abused a time or two. I'd just like to make sure I'm getting an accurate reading.

If my compression is in fact low what do you recommend I do? A rebuild isn't in my budget this season. Should I try a decade?
 

racerone

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Remove the bypass cover on the cylinder that is low on compression.-----Just 6 small screws on the side of the cylinder .---It allows you to look at the piston and rings.------Will tell the story and possibly cost you say $ 2.00 for a new gasket
 

tkdunn

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Remove the bypass cover on the cylinder that is low on compression.-----Just 6 small screws on the side of the cylinder .---It allows you to look at the piston and rings.------Will tell the story and possibly cost you say $ 2.00 for a new gasket

If I'm able to snap a decent picture would you be able to advise me based on that? I sincerely appreciate all your help.
 

tkdunn

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I figured out after posting that you were saying the problem could be with the bypass gasket. I'm certain I could identify a bad gasket but I'm no sure I'd recognise piston damage. What would I be looking for? Will I need to have the gasket on hand to put the bypass cover back on? Could this be head gasket related?
 
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