Head Gasket or New powerhead or ????

[GatorMike]

Re: Head Gasket or New powerhead or ????

I'm not an expert but I think you have found your problem there in those pictures. The starboard side of that exhaust manifold looks almost clean. My guess is water is getting in, if it gets in there you would think it would be getting into the starboard cyls too. Maybe one of the experts could either confirm or say I am wrong.

 

[modernrocketry]

Re: Head Gasket or New powerhead or ????

I agree -- I thought the same thing.
I also thought, " I wish the other side would have leaked -- it would be easier to clean! "

I plan to install the engine on Saturday -- I'll post my results.

 

[modernrocketry]

Re: Head Gasket or New powerhead or ????

I think the battle may be over... for now.
Today I put the original engine back in the boat.

I replaced the Thermostats, both head gaskets, and both exhaust gaskets. Used lots of gasket sealer on everything!
Dropped the new engine in place and fired it up.

took a while to start, but then it lit up.
Runs nice and smooth at 1100rpm (this is the idle setting for turbojets)
Killed it -- let it sit for about 10 minutes -- started it again and it turned over right away.

I let it run for about 15 minutes on the hose. Then did a compression test:
Cylinder 1: 119
Cylinder 2: 120
Cylinder 3: 119
Cylinder 4: 120

And Cylinder 3 was dry!!!!!

So it looks like it was the exhaust gaskets after all.

My pressure reducer mentioned earlier works great. Should have purchased that years ago.

The engine seems a bit more smokey than usual, so after my first trip out in the boat, if it is smokey, I'll replace all the fuel lines.

Tomorrow, I'll clean the boat up and re-torque the head bolts.

Anything else I should re-torque?

 

[bills2004svt]

Re: Head Gasket or New powerhead or ????

Yes the exhaust housing bolts should be retourqued. Did you use srew lock on them?

 

[modernrocketry]

Re: Head Gasket or New powerhead or ????

I will retorque them -- all except one. I can't get to that one.
And I did use loctite on them -- the blue kind.

 

[GatorMike]

Re: Head Gasket or New powerhead or ????

Glad to hear you got yours fixed. I think I got mine too. Won't know for sure until I take it out and run it a couple of times but the signs are good. I mentioned earlier my problem has been ongoing, I had to rebuild in the spring due to water rusting my pistons to the cyls. After the rebuild I suspected I was still getting water in the cylinders because I kept seeing just a little rust on the #4 spark plug. A couple of weeks ago she rusted up on me again and luckly it wasn't too bad I was able to break it lose with a wrench on the flywheel nut.

Anyway I just finished replacing the exhaust gaskets and head gaskets this afternoon and from the tests I did I think I've got it. Before although I had a good stream from my pee tube my water pressure gauge read zero psi at idle and just 15 psi at full throttle. Today I was reading 10 psi at idle and 20 psi at 2000 rpms on the muffs. I suspect the increase in water pressure is a good sign. Also my compression numbers look better. Although I don't fully understand why. I had been reading 125, 120, 130 and 105. My numbers now are 120, 120, 125, and 115. I don't understand the 5 psi drop on the starboard side but I will take the 10 psi increase in the low cylinder anyday this puts me in tolerance. Besides it kind of helps reinforce the thought that I got the leak fixed. Oh one other thing, I did quite a bit of sanding on the surface of the right head, it apeared it might have been warped. Time will tell if I got her fixed but it's looking good.