Logo
FULL SITE MENU

1995 Johnson 200 Venom engine noise

S

steve

Contributing Member
" The engine died on me last w

" The engine died on me last week. It started back up and then died again 2 minutes later and this time would not restart. About 4 hours later after getting it home I hooked a hose to it and it started, but you can here it making what sounds like a knocking noise. The cylinder compression ranges from 90 to 105 to 110.

Any suggestions on what may be the source of the noise. Other than that it is running fine right now. "
 
"Steve.... Fifteen pounds diff

"Steve.... Fifteen pounds difference in compression doesn't sound good. However lets hope for the best.

Remove all the spark plugs. Use a rod or a good size screwdriver that will fit freely through the spark plug holes. Hold the tool (whatever you picked out) through the s/plug hole and against the top of the piston but not with a great amount of pressure. While holding that tool against the piston, slowly turn the flywheel in a clockwise direction (same direction it normally runs in). As you turn the flywheel, the tool will indicate where the piston is. Keep turning until the piston comes to top dead center, passes top dead center, and starts down... turn until the piston has dropped down approximately 2". Now, stop turning and hold the flywheel securely.

While holding the flywheel so that it can not move, shove downwards on that tool. The tool should not be able to move the piston at all. If you can move the piston without moving the flywheel, there would have to be play (wear) either at the piston wrist pin area, or at the connecting rod to crankshaft area. You would hear a definite clunk!

Repeat this procedure on the other five cylinders/pistons. If you find a piston that you can move as with the above test, that would in all probability be the source of the knocking.

Let us know what you find.

Joe
"
 
OK..I pulled the head on the

OK..I pulled the head on the side of the cylinder that test low compression. One cylinder is scored. What opinions are there on honing the cylinders to clean them up and then run the engine the rest of the summer and rebuild it this winter.
 
"Steve... In my opinion, that&

"Steve... In my opinion, that's only going to lead to more extensive repairs. You're far better off to either get another engine, or have your present one rebuilt now. Did you check for piston movement as I described above, and if so, what did you find?

Joe
"
 
Yes I check for movement like

Yes I check for movement like you described and could not find any.
thanks for the info
 
" Honing the cylinders without

" Honing the cylinders without rebuilding it is like using a condom with holes in it. All you will accomplish is to put a bunch of abrasive material in the engine, wearing all of the cylinders and causing further damage. You risk the safety of yourself and whomever else you may take in the boat with you when (not if) it finally dies. Rebuild it now or put it away till you can afford to.
Just friendly, hopefully humerous advice,
Tom. "
 
You must log in or register to reply here.
Back
Top