Engine/Transmission (1994 - 1998) camshaft OPPS

[drice]

well I had a slight oil leak in the front gear house so I decided to pull the front housing off to fix it and this is what I found. hope yall enjoy this. I don't knwo what caused it any ideas??

 

[drice]

heres one more that makes it a little more noticeable:{



HoleshotHolset

could you add this one to your list

 

[jwilliams3]

Hmm I dont know what caused it.

How long have you had the Piers cam?



Also, it looks like that Cam is now variable timing. :--)

 

[Piers]

Did you warm the cam gear up before pressing it on? If you don't & it cocks just a hair while pressing it on it will crack the gear, once it's cracked it's just a matter of time before it breaks. If you can't find a gear close by or at a reasonable price, give me a call, I'm sure I've gat an extra one kicking around.

 

[thekidfan]

Did you call "the man"?

Cause that was sure fast response if you did OR didn't.

 

[Mad Bomber]

Cam

Piers, is one of the bussinesses that really care for there customers. That is why he's is growing so much. HE'S DA MAN

 

[csevers]

That truck ran?? like that? I have seen that before on an ISC just after a cam job 3k miles and truck wouldn't run keep poping codes for cam speed and postion sensors but all check out so we pulled it down again to find a gear just like that. Come to find out the Engine shop we were using for head and machine work didn't heat up the gear before installing it, duh we could have done that!! and a lot cheaper too.



Craig

 

[drice]

yes I heated it up when I installed the cam.



no I did not call piers because I didn't and don't think it had anything to do with any of his parts. (the cam has been in since Feb)



oh yeah it ran strong right before I left school I took a guy for a ride and smoked the tires through third.



the week before I noticed an oil leak but was in a hurry so just put some jb weld on the whole until I could get the parts to really fix it. so I know it has been broke for at leat a week but I think I broke it at the begining of Aug at some tractor pulls.

 

[csevers]

Dude you got real lucky!! Congrats, glad there is not more damage.



Craig

 

[KLockliear]

Originally posted by drice

yes I heated it up when I installed the cam.

How?

 

[HoleshotHolset]

drice: I thought I told you NOT to put the cam gear too close to the nuclear reactor fuel rods. Oh well... .



I'll add it to the 'list'... .



Matt

 

[drice]

I had the cam out so I heated it with a torch it doesn't take much heat to slide it on.



I thought . 003 was enough clearence. oh well I guess when we do it this time I will try . 002

 

[KLockliear]

Originally posted by drice

I had the cam out so I heated it with a torch it doesn't take much heat to slide it on.

That's why it broke.

 

[Diesel Freak]

KLockliear, I am assuming by your statement that you feel the heating was not uniform throughout the gear?



Would you suggest placing the cam in the freezer, and the gear in the oven at 300F to uniformly heat it?

 

[SRadke]

That explains why the gear looks so purple in the picture, it got too hot. Too much heat and the carbon in the casting changes phase and when cooled too fast becomes brittle. 300°-400° in an oven should do the trick without changing the metallurgical structure.

-Scott

 

[Joseph Donnelly]

Cummins specifies not to exceed 350 deg. Use an oven and I'd keep it down to about 325. A light press fit will remain. Put a 1/2" thick plate over the hole and tap the gear on with a hammer, quickly so it doesn't transfer too much heat to the cam. The gear will not have any discoloration at that temperature. I suggest having a buddy hold the cam vertical on a wood block.



Those who change the gear case without pulling the cam often get into the same predicament because the gear usually has to be very hot to slide back onto the nose of the camshaft.

 

[HEMI®Dart]

Originally posted by SRadke

That explains why the gear looks so purple in the picture, it got too hot.

-Scott

I thought the purple was Dykem or something similar?

 

[sbentz]

Good Answers!

You are all on the right track. Cummins has specifics in the T&R manual, and if you overheat the gear, it will stay distorted, and possibly lose the press fit.



We have had 2 of these. One was never worked on, according to the owner, but both had "torch marks" and haet marks...



Per the manual:



The camshaft gear will be permanently distorted if overheated. The oven temperature should never exceed 177°C [350°F].



Heat the steel camshaft gear to 177°C [350°F] for 45 minutes.

 

[BigYellowIron]

I thought the cam piers sells already has the gear on it?



Adam

 

[HoleshotHolset]

Adam: Dad and I did a cam in his truck - and the cam from our Canadian buddy does not have the gear pressed on.



We put the cam on a 4"x4" block-o-wood and whacked the gear on with a brass hammer to start it... . then hit it home with a 3# hammer.



Matt