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dbywaters
03-02-2004, 06:33
I have pulled the heads off my 6.5 to replace a blown head gasket, and I found small cracks in several of the pistons. The crack is located where the flame pattern blows onto the piston from the pre-combustion cups. Not all pistons have this, but some do. Is this normal or is a reason to finish pulling the block out of the truck? Cracks are about 1/4" or so long. I have a picture, but don't know how I can post it. (I Think I got this figured out)

The engine has less than 100k miles on it. It over heated twice this past summer while towing across Colorado, I recently found that the upper radiator hose spring clamp was not holding (it was not apparent in the summer)

Thanks for replies.


http://www.imagestation.com/picture/sraid105/p43ec829709390e6719f5e1c2f0c4b318/f9737ed0.jpg.orig.jpg

[ 03-03-2004, 11:46 AM: Message edited by: dbywaters ]

dbywaters
03-03-2004, 12:49
I added a picture, I've heard from a couple places that this is the result of having the timing off. It may not be fatal....whatyathink?

Doug

toyboxrv
03-03-2004, 12:56
I doubt the cracks will improve with age. I had a 6.2 that I cracked a couple of pistons, but didn't know the cause of the problem. Leaking injectors can cause cylinder pressures to spike too early. If it were mine I would pull it out and probably change all the pistons.

dbywaters
03-04-2004, 12:08
Well, I was kinda hoping that they would not get any worse :rolleyes: .....thanks for the reply though.

It is kind of an expensive job. I am fortunate enough that I have it in my own garage and I can do most of the work.

Doug