Compression test questions
#11
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i say do the test yourself.if you pluck it up,you got nobody to blame but yourself,at least you will learn.i have to agree w/dennis ,why would anyone drive a ford or a harley?lol jus kidding guys.
#12
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then your advice that he do it himself because " what can it hurt" is stupid. and i don't care how many books you wrote 30 years ago.
#13
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"then your advice that he do it himself because " what can it hurt" is stupid. and I DON'T CARE HOW MANY BOOKS YOU WROTE 30 YEARS AGO!!"
Steve, will you adopt me??? YOU ARE MY HERO!!!!!!
Steve, will you adopt me??? YOU ARE MY HERO!!!!!!
#14
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T-rav-find someone qualified and do a full survey, transom replacements are exspensive and should really be checked for moisture on a 14 year old boat and they could check compression and hopefully do a leakdown test too as the 502 mpi's used metric low tension rings and are prone to leakdown problems stock. If you do it yourself pull the fuel pump fuse or unplug distributer signal wire and un-plug the coil so you don't burn up the coil (I have done this) and you don't wash motor with a bunch of fuel every time you crank it over, Smitty
#15
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There is a certain speed that is expected with every make and model of boat depending on the HP. If the boat does not hit that mark then somthing should be looked at.
Listen for a mis under load and listen for anything unusual. The transom and stringers should be looked at, take a rubber mallet and tap around, listen for hallow or different tones. If you can get a moisture meter that would help.
Listen for a mis under load and listen for anything unusual. The transom and stringers should be looked at, take a rubber mallet and tap around, listen for hallow or different tones. If you can get a moisture meter that would help.
#16
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I don't think the OP was saying him doing a compression test himself will replace a full blown survey. I think he was simply asking if he chooses to do a comp test himself should the engine be warm or cold.
IMO warm is better as problems show up as the metal expands. But the problem is too warm and it's a PITA on a boat.
I always check my sleds warm as they are obviously easy to get to the plugs. I've seen wounded sleds have decent compression cold then warm them up and it drops significantly. But ask 5 people the proper method and you'll get 5 answers. Some say warm, some say cold, some say throttle wide-open, some say it doesn't matter, some say 3 pulls, some say pull until the gauge quits going up, etc, etc.
Smitty gave you good advice. And don't get hung up on the actual number as gauges can vary(unless they are all very low then try a different gauge). The important part of a compression test is the difference between the cylinders.
IMO warm is better as problems show up as the metal expands. But the problem is too warm and it's a PITA on a boat.
I always check my sleds warm as they are obviously easy to get to the plugs. I've seen wounded sleds have decent compression cold then warm them up and it drops significantly. But ask 5 people the proper method and you'll get 5 answers. Some say warm, some say cold, some say throttle wide-open, some say it doesn't matter, some say 3 pulls, some say pull until the gauge quits going up, etc, etc.
Smitty gave you good advice. And don't get hung up on the actual number as gauges can vary(unless they are all very low then try a different gauge). The important part of a compression test is the difference between the cylinders.
#17
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And what's wrong with a guy doing his own comp test? If a boat I was thinking about buying was near me I would check it out first myself. If it checked out then I may have someone more experienced survey it. If it doesn't they you simply walk away and save yourself the money for a survey. Seems logical.