Changfa Head troubles

[akghound]

Just passing on info here, not complaning, the engine is a good one.
On a new Changfa 1115 Engine / Genset head was cracked under the exhaust valve spring, sort of hard to find. Anyway I recieved a new head. I installed it and after running for about 4-5 hrs the stud that holds the air cleaner in place broke loose from it's weld (inside the piece between the manifold and the air cleaner), rattled free from the top and traveled down through the intake manifold, under the intake valve, across the inside of the cylinder to the exhaust valve. It damaged both valves, bent a push rod and scared the piston a little. What Luck Yuck!! Anyway, I was able to put the valves from the cracked head into the new one and get her back up and running.
These are certainly tuff engines and are easy to work on.
Ken Gardner

[rcavictim]

That stem broke free also on my JD175A but fortunately did not fall down the intake pipe.  When this happened I decided to fabricate a whole new intake pipe and paper element air filter assembly.  No chance of an accident like your`s happening now.  You got pretty lucky I think all things considered.

[okiezeke]

Here's my casting defect pic.
Zeke

[biobill]

Nothin a good thick gasket and a bunch of goop wouldn't fix, huh Zeke      You gotta wonder why they machined it as far as they did.

[okiezeke]

The defect is at the 8 O'clock position about 1/2 inch out from the center of the pic.  It's kinda hard to see, inside between the valve and the face of the head.  Can see where the water was coming in and left a trail.
Zeke

[mobile_bob]

Zeke:

your defect probably was caused by a core shift when it was casted
and my bet that area is very thin and not a good candidate for weld repair.

at least before i would try to weld it, i would explore a bit to see how thin it is there.

bob g

[okiezeke]

Bob,
I agree, looks real thin to me too.  I think I'll clean it up, fill it with JB weld, and keep it for a spare for the spare.  At least if it starts leaking again when running it is very obvious from all the water coming out the exhaust.  Sure hope a changfa head is identical.
Zeke