Rebuild or not to rebuild

[spanky0077]

Hey Guys so far this forum has been great and I like the advice.
I have a 1987 Johnson 150 gt. I love the boat a 1987 Ranger 360V and the motor, I like the vintage look and the performance.

My compression is between 80 and 90 in all 6 cylinder and I know it is getting tired. Would an engine rebuild help improve compression and performance. I was thinking of doing it this fall. Is it worth it? Plus i do not have the cash for a new motor at the moment.

She gets on plane quickly and goes like a bat out of he# and a lot of other think my Ranger flies. They were impressed for the age.

When getting quotes, how much should I be expecting to pay and I was also thinking instead of rebuilding, just buying a new power head?

 

[jchristi]

Re: Rebuild or not to rebuild

if they are all within 10% probably just needs a carb rebuild.

 

[spanky0077]

Re: Rebuild or not to rebuild

How do I check to make sure the VRO is working properly?, I have been reading a lot of threads about the reliability of them.

Also would a carb have something to do with the compression? I love the boat and runs great. Just a little worried

 

[hidef]

Re: Rebuild or not to rebuild

Place a mark on the fuel tank and run the boat if the oil level drops then you know it is working. If you are concerned about the VRO run 50:1 premix in the fuel tank an disconnect the VRO.

The carbs have nothing to do with compression however if they haven't been cleaned in years it wouldn't hurt. Your compression sounds like it is fine. When doing compression tests you look for all cylinders to be within 10%. Yours are you really can't trust the compression gauge for bang on accuracy another gauge might give you higher readings. You could also do a decarb and see if that raises the compression. If you have a buildup of carbon that can cause some funky reading also.

I don't think you have any issues if your speed is still there and she is quick out of the hole you should be fine.

 

[Bob_VT]

Re: Rebuild or not to rebuild

Have you de-carbed the motor? You might gain 10 PSI per is it is needed

 

[JB]

Re: Rebuild or not to rebuild

Those compression numbers are spot on for a healthy 150 V6. Rebuilding would gain you nothing but a much, much lighter wallet.

 

[spanky0077]

Re: Rebuild or not to rebuild

Thank you for all the help

 

[Solittle]

Re: Rebuild or not to rebuild

Ahhh - - - - - Ifn it ain't broke - - don't - - - -