In the process of getting the head cleaned up and getting it to the machine shop to get re-surfaced we noticed 3 cracks in the head... It split coming off of the valve on pistons 3,4, and 5.

A new head should be here tomorrow so I'll have it screaming again!!

 

I wouldn't be surprised if most of the performance guys on here have cracks in their heads. It's been an issue since the 12V days. I'm not convinced that the cracks are a problem, though.

 

2 of them I'm not concerned with because they are just hairline but the biggest one is 3/8 long. Do you think that one would cause a problem?

 

I think it really depends where the cracks are, but in a lot cases they seem to originate from the valve guides. With as large of a casting as our heads are I really think it's impossible to not have cracks over time, especially when raising the cylinder head temps when bombing them like we do. If the cracks get into the seal areas then yes, that could cause problems, but IMO a large number of them are benign.

 

Does anyone else have an opinion on the cracks?

 

it doesnt sound good, sorry to hear about your troubles.

 

I had 15 cracks between the valves on my 00 head. It did not have press in seats so we machined it to hold oversize seats from a 05 engine. Machining took all the cracks out. They were not deep and were causing no problems. I would have never know about them if I had not pulled the head for o ringing. I think they are very common if not normal. I have yet to see a used 24v head without cracks. If they dont go to water or loosen a valve seat I would not worry about it. Tim

 

If I got it machined how do I know where to get a gasket? My truck had the 45 (thicker) gasket on it from the factory.

 

My head is cracked and has been since about 1968

 

not to hi-jack, but where did you get your additional head from?

I am with the other guys, I think the cracks are from bombing, and as long as they are just surface cracks, I wouldn't be too worried about it

just my opinion

 

I did some searching around and I bought it from Cummins. Several bills cheaper than some of the prices I got quoted... I think some of the shops that are selling them *new* are making some serious $$$...

From what I hear now, the old head isn't as bad as I thought but I already made my move with the local cummins store and I won't back out...

 

I felt very fortunate when I took mine off and couldn't find any after cleaning.

 

I noticed several cracks in mine when I had it o-ringed and ran it anyway...no problems yet.

 

Luken, My head didn't have a single visible crack in it and then they pressure tested it and all was good . Cracked heads in the valve area are normal for those running higher EGTS. Valve cracks are ok...a stress reliever to the head. Cracked coolant chambers and the head is toast. Now you have a head to play with. You can either polish and port it yourself or send the head out and get some polish port and valve work. It also makes a nice paper weight or desk ornament and it is awesome for front arm curls. ks

 

I don't doubt that! They are pretty heavy... I guess I have a head for sale LOL