compression help needed johnson150

[wilsha]

looking to buy boat, but need some help. 89J150ST compression reading are <br /><br /><br />left bank right bank<br /><br />97psi 100psi<br />95psi 98psi<br />95psi 83psi<br /><br /> is this a serious problem, and is this a costly situation. thanks

 

[JB]

Re: compression help needed johnson150

Ahoy, Wilsha.<br /><br />#6 is too low.<br /><br />Pass on this one unless it is free.<br /><br />Red sky ay night. . .<br />JB

 

[DJ]

Re: compression help needed johnson150

She's REAL tired!

 

[G DANE]

Re: compression help needed johnson150

Hi<br /><br />A difference of more than 15 is too much. <br /><br />However these motors usually have compression around 130 !! are you sure of your meter - have you tried it on something else. If compression is that low, id say like John, its worn out.

 

[G DANE]

Re: compression help needed johnson150

I have to explain a little bit more. Lets say your meter was wrong and the readings Were: 127, 130, 128,128,125, 113. Looke better hah !<br /><br />The problem could maybe be stuck rings on one, if the motor sat for long. Probably WD 40 or decarb could loosen it. But this is taking chances. If i shold buy this motor, for a reasonable price, not next to scrap value, id like to see an improvement first. If readings are right, it sure has a lot of hrs on it.

 

[jwhite]

Re: compression help needed johnson150

It really depends. The rings could be stuck from carbon, you could try valvtec or some other kind of carbon cleaner and see if that gets the compression back up, or it could be a blown head gasket or a blown motor. The best thing to do is take it to a professional before you buy it and let them check it out. Low compression doesn't always mean the motor is blown but it does show that the previous owner or owners didn't take good care of it so unless you can get it for a good price then i would try to find something else.