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Routine compression testing?

Seadeals

Seadeals

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My MR1 engines have been running great. I had engine cylinder compressions tested when I bought the boat; but after several seasons I am curious if they have changed any. I really haven't seen any procedures for testing. I suspect it is as simple as pulling all plugs connecting to the test cylinder and motoring a few seconds with the lanyard pulled. Is there a formal procedure? Will any compression gauge work? I am also curious about hours accumulated. Is there any other way than dealer (over an hour away)? I have a YDS cable (only) but have not been motivated enough to accomplish the other steps to make it work... a bit intimidated.
 
Big Shasta

Big Shasta

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Should be as easy as
Pull all the spark plugs out.
pull lanyard,
install tester in cylinder
push the button on the side of your throttles so you can go wide open throttle and it will still crank.
Turn it over for a few compression strokes on the cylinder your testing (should be just a few seconds).
Record results.

Most compression testers come with adapters for different plug sizes, it should be easy to find the right one.

Setup your YDS, you'll be glad you did.... it's pretty simple if your cable works. (mine doesn't work and I haven't messed with it to figure out why) Don't take it to a dealer.
 
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Seadeals

Seadeals

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Looks like we are in the same boat with YDS. It probably is not that difficult to make it work; but one glitch and it is too much of a headache. I just replaced our laptop (damaged-dead) with a MacBook Air. I assume YDS is windows based, so I am short a laptop for it. If I don't find anyone close by, I may just have to build a Frankenlaptop from pieces of previous machines get the software and give it a try. I am sure I will get motivated if I ever throw a code!
 
Mpalozzi

Mpalozzi

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Is it worth it if your still getting compression? I know this is an old post but if your getting over I'd say 90psi per cylinder are you even going to rip apart your motor just to change the rings?
 
Jgorm

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Yes. Run it any time you change plugs. Harbor freight tester works fine. Pull lanyard, throttle at wot and crank until it didn't go higher. Purge gauge and repeat at least one more time. I got 195, 100, 165, 215 so I'm tearing into the engine. Compression only takes maybe 5 minutes, might as well run it.
 
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