Kev_79<br />One of the boat motors the Compression is<br />135 on both and the low Cylinder is 110.<br />on the other boat motor the compression is<br />1 0125<br />20115<br />3080 Low<br />40100<br />Is this good or bad
Not necessarily bad, check with dealer to find out lower limits on compression. When the motor gets hot, the rings will expand, maybe giving you a closer ratio to the other cylinders. Do they run good. If not, could need a ring job, or head gasket. If they run good , run em! Anymore question, keep them coming. GL
A few days ago I just put Idle tubes in the Carb because I thought that was the problem<br />with it not idleing right,the Idle tube were<br />cracked.But after puting the tube in it still<br />didnt run right so I did a Compression test on it....It has new Idle tubes now but no luck.
JB<br />I don't know what the 65hp Mercury boat motor<br />compressing should be.The motor we have on the boat will not Idle at a slow speed,I did<br />change the Idle tubes because they were cracked,but that didnt help a thing.I just do<br />not know about the compression.
Kev_79<br />When I put the Idle tubes in I preset the air fuel mixture on both carbs to 1.5 turns out.And checked the Butterflys and both were<br />in the same possition,then started up the motor and it still run Bad I tried to adjust<br />the air fuel mixture and still no help.it will run fair at a very high Idle if you keep<br />the cold start lever up at about center position.But when you return the cold start lever to the down position it dies.I also checked for leaks around the Carb base gasket<br />and found no leaks.
Good start, I would check timing next. Call dealer for specs, I think should be between 2 and 4 degrees advanced at idle@600-700rpm in gear. This would be what I tried next if you haven't already. Let me know if and how it goes. GL
