dropped a valve seat now what? Rebuilding the engine

Ascholting

Ascholting

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Dropped a valve seat now what? Rebuilding the engine

Ok last weekend, my last hook of the year I lost a valve seat and tore up cly#1 bad so I’m pulling the engine. Now I was going to do a p-pump swap this winter anyway I already got a CDS pump, But now I don't know if the head is good yet and if I should change the pistons and buy a 12v head to put on my 24v block and port the heck out of it and put a hot 12v cam in it. Or stay 24v head and go that way build up my 24v?

Any thoughts, ideas on what I should do?

Truck is not a 100% puller but almost don't work it any more just cruise it on the street every now and then.
 
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If you do go back with the 24valve head. You better make sure you get oversized pressed in seats or it will happen again. Better have them pinged in also. I was in your same boat last year and ended up putting another head on the truck without doing anything to the seats. Evertime i run it hard in the back of my mind i keep my fingers crossed a seat doesnt drop again. I was lucky the first time and it didnt even scar up the piston.

You can trick a head out that has pressed in seats. But its going to cost a little extra but not much. Like i said you better go with oversized seats, and have them pinged in.
 
is it true the HO heads are more prone to seat failure than the SO??
 
Yea if I’d been told about that when I bought this head! Dose Cummins make them or someone else?

Thanks for the help
 
I was told you can put a 12v head on a 24v block as long as you change the pistons is this correct?
 
I believe it was a diffence in metal used in the seats. Something to the affect that the HO's can't withstand the high heat and fast cooling during pulling, racing, ect.
 
yea it makes a mess out of things in a hurry, ill get some pics this week.
 
I was told that the NON -HO motor did NOT have valve seats by Jeff....I've even bought one (also o-ring'd) that i'm going to install with my new springs so as not to have this problem when I got twins.....

I'll call Jeff and see, but I know he's done work for people before with CR's that dropped seats and recommended this same thing....
 
The earlier SO engines did not have press in seats. Rather, induction hardened faces in the seat area of the casting. They cant drop out.

Those were used from 98.5 and up until about 2001. Cummins is no longer making the induction hardened head casting as far as I know.

You would need to find a used head somewhere and hope it is not cracked. The old 24V heads without press in seats cracked more than I would like to see.
 
Big Swole said:
I was told that the NON -HO motor did NOT have valve seats by Jeff....I've even bought one (also o-ring'd) that i'm going to install with my new springs so as not to have this problem when I got twins.....
Click to expand...

You may want to check that head over for valve seats really hard when you get it, or if you already have it. I believe Adam did the same thing, specifically bought a new SO head from a site sponser (wasn't Jeff) with all the workings so he would not have this problem, and still dropped valve seats.

Adam, I would guess that about any machine shop that can work over a head should be able to get new valve seats (oversized to press in). May just have to call one and see...
 
GOT-Torque said:
You may want to check that head over for valve seats really hard when you get it, or if you already have it. I believe Adam did the same thing, specifically bought a new SO head from a site sponser (wasn't Jeff) with all the workings so he would not have this problem, and still dropped valve seats.

Adam, I would guess that about any machine shop that can work over a head should be able to get new valve seats (oversized to press in). May just have to call one and see...
Click to expand...


Well, this head isn't coming from Jeff himself..Just a close customer / friend of his....I've seen it and it's still at Jeff's shop....Valve train is still in it...Can I tell if it has seats just by looking....

Gotta call into Jeff to see if he can double check....I haven't actually paid for it yet.....BTW, What would be a good price on a head with valvetrain that has had a freash O-ring job be worth.......Wanna know if I getting a deal or not.....The guy said it was about $500 just for the o-ring job....?????
 
GOT-Torque said:
You may want to check that head over for valve seats really hard when you get it, or if you already have it. I believe Adam did the same thing, specifically bought a new SO head from a site sponser (wasn't Jeff) with all the workings so he would not have this problem, and still dropped valve seats.

Adam, I would guess that about any machine shop that can work over a head should be able to get new valve seats (oversized to press in). May just have to call one and see...
Click to expand...

I did and didn't look at it very close when i got it, I put it on and figured i was done with it. Now the place i bought the head from has changed hands i didn't even ask.
I'm thinking the head is not going to be any good it really beat the heck out of things so i'm kinda thinking about putting a 12 head on it.
Ill no more this week if it rains and i have time to get it out on the stand and look things over.
 
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