After countless hours of trying to find what the normal compression reading on a Johnson 50hp 2 cylinder 2 stroke with no luck I figured you guys could give me some advice. It is a 2001 model and currently getting 105 on the top and 100 on the bottom, I've read anything over 90 on this engine is good then I've read 120-135 is what it should be?? Model number is JP50PLSIG
I don't think I've ever seen compression numbers in any manuals. 105-100 sounds about right. Now is someone has done some work to the heads it may be up in the 125 range.
That's kind of what I was thinking. Also not sure why they are so greedy with the compression numbers but sure can't find anything about it in this particular engine. It runs good so no worries was just curious if that was a bit on the low side. Probably will get rid of the vro soon as I find the best way to go about it...
Why...Originally Posted by R0lltide
Age and treachery will always overcome youth and skill !!
The oil tank is about the size of a battery so I could fit another battery in. Plus as long as I mix it myself I know it's getting what it needs. I have no plans of doing this anytime soon. But i have noticed it starting get a little oily/greasy under the carbs and vro that is making the splash well look horrible and a mess to clean. I figure if it's needs work I'll just delete it..
Use the cap that came with the motor and remove the oil hose going into it. Secure the cap that goes over the oil inlet with a zip tie. Unhook the 4 wire harness on the VRO pump and disconnect two wire harness at the motor for the oil tank. you can now remove the oil hose, oil tank harness and oil tank from the boat/motor. Mix you oil at a 50:1 ratio. 16 ounces of oil to 6 gallons of gas.
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