3.0 compression check tell me I have hope

[thejeep007]

Re: 3.0 compression check tell me I have hope

Valve

 

[aerobat]

Re: 3.0 compression check tell me I have hope

I would bet you had a valve stuck open from rust that caused the 0 compression reason.

i think thats correct. the piston does not has a hole, so not much options for "zero" compression.

 

[thejeep007]

Re: 3.0 compression check tell me I have hope

More pictures. Just a small pit in piston. Cleaned it w a pick.

 

[thejeep007]

Re: 3.0 compression check tell me I have hope

More pictures. Just a small pit in piston. Cleaned it w a pick.

 

[thejeep007]

Re: 3.0 compression check tell me I have hope

The 3-4 runners vs 1-2 runners

 

[thejeep007]

Re: 3.0 compression check tell me I have hope

Ok well the rain is moving in. My hypothesis, whoever worked on this just used rtv silicone on the manifold elbow connection. This leaked water into the intake, mainly number 4-3 cylinder. This pitted and rusted valves causing number 4 valve not to seat. Remedy, put correct gasket on elbow manifold, replace the bad valves, hone the cylinders, make sure rrockers are adjusted, happy boating??? If not steer me straight gang. Thanks again.

 

[Don S]

Re: 3.0 compression check tell me I have hope

Pull the elbow of the riser and check the gasket surfaces of each. I think you may find your problem.

You boat in salt water by any chance?

 

[thejeep007]

Re: 3.0 compression check tell me I have hope

Looks like you are thinkin what I am don. Water from manifold into cylinder. My fix sound good to you?

 

[Idlespeedonly]

Re: 3.0 compression check tell me I have hope

Did you notice a stuck valve when you took the cover off?

 

[thejeep007]

Re: 3.0 compression check tell me I have hope

Turned the crank and didn't see any obvious stuck valves no.

 

[Don S]

Re: 3.0 compression check tell me I have hope

Looks like you are thinkin what I am don. Water from manifold into cylinder. My fix sound good to you?

Not really. Unless you plan on complete disassemble of the engine, and new rings. You can't hone a cylinder with the pistons in it.

The head needs to sent to a machine shop and have a complete valve job done, not just throw a couple of new valves in it.

As far as the manifold and riser. What condition is the sealing surface in? make sure it's full width and shiny metal, not just soft black carbon.

 

[Idlespeedonly]

Re: 3.0 compression check tell me I have hope

From the pictures, I dont see enough damage to not have any compression. At a bare minimum have the head reworked put it back together and see how long the rest will last.

 

[thejeep007]

Re: 3.0 compression check tell me I have hope

I have lapped valves in heads before... The machine shop is not cheap and buying a home. Might be able to get another head for short money...

 

[thejeep007]

Re: 3.0 compression check tell me I have hope

Wouldn't the amount of carbon on the inside of theintake valve tell you it wwas hanging up?

 

[Bondo]

Re: 3.0 compression check tell me I have hope

I have lapped valves in heads before... The machine shop is not cheap and buying a home. Might be able to get another head for short money...

Ayuh,... That motor, Might be a rebuildable Core motor, a Machine Shop could access it,...
Or not,...

Yer plan has 'bout a 0% chance of Happy Boatin',....

The Escape Plan is to find a runnin' take-out motor, or a Rotten boat, with a Runnin' motor....
Figure $800/ $1500.... try craigslist maybe,...

 

[thejeep007]

Re: 3.0 compression check tell me I have hope

Your saying the whole motor bit it....

 

[ricohman]

Re: 3.0 compression check tell me I have hope

That vertical gouge looks like a busted compression ring.
At the minimum you need to re-ring and have that head rebuilt. The used motor out of a rotten boat is a good idea.

 

[aerobat]

Re: 3.0 compression check tell me I have hope

don,t you think that just a new valve will do the job as a quick and dirty budget solution for some seasons ? the cylinder does not look that bad .

of course check/replace the manifold to exclude new water

 

[Bondo]

Re: 3.0 compression check tell me I have hope

the cylinder does not look that bad .

Huh,..?? in the 1st picture, I'm doubtin' a .030 over-bore will clean it up,....

Those cylinders are waaaaaay past a "Hone Job",....

 

[bonzoscott]

Re: 3.0 compression check tell me I have hope

Budget job: As long as you have more time than money, clean up - lap valves yourself - new head gasket - change oil and try it. You may get a seasons use. You need to get it running and check for water intrusion again. go from there....