6.9 heads - are cracks common?

[Knuckledragger]

I disassembled a 1985 6.9 engine with 100,000 miles on it thinking that it only needed a head gasket, but found that the heads have little tiny cracks between most of the intake and exhaust valve seats. I do not believe there is any chance for coolant leakage, as there does not seem to be a water jacket in the area. I wonder if this is a common sight, or am I just unlucky enough to have some junk heads?

If that is the case, does anyone have a set of good heads in southern California for sale?

 

[typ4]

There is a water jacket there, cracks there are bad. The only way to rule that out is to have them pressure checked, but even then they cracked because of excess heat,soooo?

 

[david85]

I know this is VERY common on the chevy 6.2/6.5 diesels, but in those cases, its not a problem unless it actually goes into the valve seat. I haven't heard of it being a big problem with 6.9s though. Although cracked heads can happen on them.

 

[In2Fords]

I would suspect something is causing this, Would incorrect fuel amount cause this?

 

[icanfixall]

The heads with the casting number 1809199C1 crack easily but the heads with the casting number 1805296C1 are the better heads. International seemed to fix the head cracking problem with the later heads.

 

[Knuckledragger]

Thanks for the responses. I purchased the truck (barely) running, knowing the head gasket had failed between cyl #5 and 7. There is also evidence of heat in the trans oil, and it lived in the desert for about 10 years. Guess it is time to search for another set of heads.

This is a worthy although expensive project. The truck looks to the world as if it has just driven off of the lot in 1985. Perfect paint and interior, no scratches in the bed, even. I guess they just hauled stuff and drove to work.

 

[hesutton]

Getting these motors too hot certainly will crack the heads. Cracks where you're describing them like stated above is not good. Sorry to hear the heads are likely bad. But, the rest of the truck sounds very cherry. You will at least need new head bolts for your engine. You cannot reuse/retourqe them. ARP head studs would be the best option, but at least get new bolts.

Heath

 

[Knuckledragger]

I have ordered ARP studs along with .020 oversize pistons. A real shame, because the bores were fine until the water sat in some of them and etched the walls.

The casting numbers indicate that these are the early, crack prone heads. Good news is that there is a diesel f350 truck in the local pull your own parts wrecking yard that is about to be put out for scavenging. Heads are $50 each. I will be there early on Saturday (the day they put out trucks) to tear it apart. It is currently complete. Anyone need parts?

 

[typ4]

Leave the rockers and injectors on the heads and maybe they will be free.
Where is your nearest pik a part. I used to ravage the one in ontario on Milliken,I think that is the road.

 

[k_williams1982]

If punkmechanic changes his mind about getting the parts motor off me, I have a good set of 6.9 heads on the engine that lost the bottom end.

 

[icanfixall]

Knuckledragger... Your in for a long day at the "yard"... I hope your not going to the pick-a-part in Monrovia. I was in there and found 7 or 8 .357 magnum bullets in a 928 fuel filter... Like someone was hiding them there for someone to pick up later on. I wont ever go into that yard again... At least not without packing.... All the yards I enter my name is listed as Ben Dover of LA...... Or the ever popular Mike Hunt of LA....

 

[LCAM-01XA]

All the yards I enter my name is listed as Ben Dover of LA...... Or the ever popular Mike Hunt of LA....

Hello, I'm Ivan Grozny from NY, nice to meet ya

 

[Agnem]

Don't be too disuaded by older castings. I've got two trucks with Model A engines and have had no problems. It's all in how you treat them.

 

[Knuckledragger]

Knuckledragger... Your in for a long day at the "yard"... I hope your not going to the pick-a-part in Monrovia. I was in there and found 7 or 8 .357 magnum bullets in a 928 fuel filter... Like someone was hiding them there for someone to pick up later on. I wont ever go into that yard again... At least not without packing.... All the yards I enter my name is listed as Ben Dover of LA...... Or the ever popular Mike Hunt of LA....

Monrovia is the one. I have a machine shop in the neighborhood and have never had any trouble with the locals. You might be surprised what you can find in some of those cars. I have seen bullets too. I sometimes collect enough money to pay for admission.

If it isn't raining too ******* Saturday, I expect to spend about 3 hours getting them out if they are OK. Unless the heads in Oregon are available from Kenneth.

 

[k_williams1982]

Unless the heads in Oregon are available from Kenneth.

Let me see what I can figure out today for you. PM me a number to call you at and I'll call as soon as I know more. I don't know where Pasadena is, but my old boss is headed to Santa Rosa next week and I might be able to have him take a set that far for me, and we might have a a volunteer "parts runner" going from Santa Clara to Santa Rosa. If I can arrainge it so the heads go down with my boss, that'll at least cut the cost of shipping down on these things. If I can get a set, they'll be complete (rockers, valves, and push rods).