results of compression test

[elkman]

volvo AQ170 inline 6 150,150,160,120,130,120, when i put a teaspoon of oil in the last 3 cylinders and retest the compression came up to 140 in the last 3 cylinders. this motor was not run for about 1 year and when i got it running the oil turned milky, do you think i have blown head gasket or could there have been enough condensation in motor to turn oil milky. THANKS

 

[Don S]

Re: results of compression test

After a year, I really doubt condensation is your problem. If not properly drained and winterized, it could be a head gasket (Doubtful) or a cracked head, block, or oil cooler

 

[elkman]

Re: results of compression test

what would be my next steps to try to narrow it down, i did pull the oil cooler apart and did a visual, did not see anything but i did not do a leak test, i did not pay much for this boat and when i had it started it seemed to run good so i am willing to put some money into it if it is salvaegable.

 

[Don S]

Re: results of compression test

Taking stuff apart and looking at it won't tell you much. Pressurize the cooling system and look & listen for leaks.

One note, In general, FREE boats are OVER PRICED.
Usually very expensive to fix and costs way more than the boat is worth when fixed.......... That why they are FREE or very cheap. What shape is the transom and stingers in (dry rot) how about the drive?
The 170 has mostly NLA (No longer available ) parts from Volvo. When you can find them, they are expensive. Think about what you are getting into with this project.

 

[elkman]

Re: results of compression test

transom and stringers are solid, boat is a 1971 glastron crestflite.I need one housing part for the outdrive which i have located for $30. outdrive seems to work fine. do you need special tools to pressurize the cooling system and would this be my next step and how much pressure would you use . would you fill system with water first or just use air and check for leaks with soapy water?

 

[Haut Medoc]

Re: results of compression test

Use air only.....
Water doesn't compress.....
Pressurize it & listen......
You'll hear it.....
A brush with soapy water for the external portions......
I'm betting cracked block........:'(

 

[Bondo]

Re: results of compression test

how much pressure would you use . would you fill system with water first or just use air and check for leaks with soapy water?

10, maybe 15psi is Plenty,........

Drain the Water out,+ usually just Listening is enough to Find the Problem.........

do you need special tools to pressurize the cooling system

You'll need to build whatever it takes to Block Off the part of the system you're Checking,......
A way to introduce the Air,....
A way to Hold the Air,...
And,...
A Pressure Gauge is Helpful, but Not really Necessary.......

'Course, Compressed Air........

 

[elkman]

Re: results of compression test

I am not having much luck pressure checking my motor, dont have the proper eqipment, what could i expect to pay to have this professionally checked and daignosed, motor is inline 6 and very accessible. thanks

 

[Gary H NC]

Re: results of compression test

Most shops are around 75 bucks an hour.I would guess a one hour minimum labor charge to test that.
I had a shop do a leakdown for me one time,They said no charge if i let them do the repair.I was lucky it was just a headgasket..