Weirdest cam damage I have seen...

[H@xtGSX]

I have seen a lot of damage done to an engine from various causes, but I have never seen this. This isn't my engine, but I had to show this because I don't even know what the hell to say to the owner about this. This is an HKS cam, and the only journal damaged was the #3 intake cam journal. There is spalling on the cap edge. I have no clue how this could have occured. This may have been involved in or may have resulted from the timing skipping and the valves getting hit. Anyone else seen anything like this??

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[007jimmy]

overtighning the caps will do that.. its just from excessive heat.

 

[H@xtGSX]

These caps were torqued correctly though, and they moved freely prior to this.

 

[1Gina2G]

This just recently happend to me, a 'friend' put my head together and just because of a small amount of dirt durring installation, 2 cam journels became worn out. since there's no cambearings for these heads the oils the only thing between the camshaft and the head so the head becomes junked.

the cam caps are made with the head too so if a single cam cap goes bad the whole head is junked. I'm sure it was either some dirt or overtigtening of the cam caps that did it. though.

 

[bryanwheat]

overtighning the caps will do that.. its just from excessive heat.

Incorrect. You will snap the bolt of strip the threads from the head before you deform the cam bore. This is likely from the wrong cam cap, a warped head, a clogged oil passage to that journal or a wrong clearance.

 

[H@xtGSX]

Some of the damage looks like it is heat related and that the metal actually melted. The journal is scored about 3/32" deep in a strip about 1/4" wide, directly in the center of the journal. The cap has what looks like peening marks from being struck extremely hard. I've never seen this occur in a single journal so bad and the rest be damage free. The cap is the correct cap. It's number matches with all the other caps and it is in the correct position. The oil passage being blocked is as good a guess as I've heard, but would it expand the metal that much??

 

[DSMnoobsause]

I've seen this on other cars (non DSM) its caused by debris clogging the oil passages and starving the journal of oil.

 

[TSIfreek]

Incorrect. You will snap the bolt of strip the threads from the head before you deform the cam bore. This is likely from the wrong cam cap, a warped head, a clogged oil passage to that journal or a wrong clearance.

Bryan nailed this one again.

 

[BogusSVO]

Lack of oil.... something got in there and blocked the oil passage to that journal.

aA divit on the cam or one grit of sand is all that is needed.... it cuts and starts the metal chips forming, they block the oil pasage little by little till fully clogged.. then no oil then heat takes over galling and ripping the soft alum cam journals

 

[H@xtGSX]

I have seen shredded bearings from debris, but not like this... It looks like it blew molten metal out of the side of the cap. Definently a lesson in why cleanliness and attention to detail when building an engine is so important.