I want to check my compression. I have a fear that I am pumping fuel into my oil. I just checked it and the 20/50 oil seems very thin (20 dune miles old). It drips off the dip stick and when whiped on a paper towel it absorbes quickly. I think it smells like fuel too, but I may be psycing myself out.

How do I know if fuel is in my oil??

Can you please tell me which brand/model of compression tester is the best. And where to get one.

I believe compression should be 140 min 180 max???

Thanks.

Blue

 

The best one would be a snap-on, though they are very expensive.

You can get a cheaper brand, but they usually read pretty low, and should only be used for comparing your own motor when fresh to your own motor after use. For example, I got a cheap one, and it read (consistently) 20lbs less than the actual reading my motor builder got off of his expensive gauge.

You cannot trust most (cheaper) compression testers to give you a true compression reading.

 

BlueLeader does your cam still retain the factory decompression pin. If it does it will be hard to get an accurate reading.

Maybe it would be best if you get an oil sample and have it tested. Are there any large CAT dealers in your area, they should have there own oil analysis laboratory. [img]i/expressions/face-icon-small-smile.gif[/img]

 

A leak down tester is the best thing to use for determining cyl. problems. Being a pilot you should know better.[img]i/expressions/face-icon-small-smile.gif[/img]

 

Does the oil smell like gas?

 

we have the plane oil tested by Modern Machinery (PO Box 16660 Missoula, MT 59808-9901). I will send them a sample. But I am going to Glamis on Friday and want to do some tests myself. I am short on time but leak-down will answer my question.

 

go buy a cheap one at least you 'll have an idea plus it will tell you what you really want to know test it at wide open throttle, after it's warmed up, see what comes up if it's low do a second test with a table spoon full of oil down the plug hole if it goes up you know that yours rings are bad if not and it was low you need to check your valves
good luck
DAMAGE

 

OH YEAH I THINK IT'S 149 TO 190 I THINK

 

How do you run a Raptor at wide open throttle if the compression tester is in the spark plug hole????? Dumbass

 

The throttle has to be held wide open so that there is no restriction of air coming through the carb into the cylinder.