Engine/Transmission (1994 - 1998) Fire rings??

[Cummins360]

Hi can someone please tell me what in the world fire rings are compaired to o-rings???? And what the advantages and disadvantages are of each?

 

[KingS]

fire rings are a thick piece of mild medal that it connected together as one piece and they take the place of the original ring on the head gasket.

Mine where approx. 103 thick and you cut a groove in the block or head about 32 thousands deep or so, or split the difference and cut a ring in both the head and block then put the ring in it and then the head gasket that goes with them put head on then stud the head.



Oring is a small piece of wire put into a smaller groove in the head or block. then the head gasket it put on normal gakset is usally used and the head is bolted on,



The benefit of Fire ring is it will hold alot more compression and boost pressure the amount is determined on if you use 12mm or 14mm head stud but it ranges normally from 70 to 100+psi boost.



Oring is the same benefit but only usaully hold 50 to 60psi boost most of the time.

 

[Bandit1]

My motor was fireringed, some pics in my readers rigs.

 

[bluthndr]

The benefit of Fire ring is it will hold alot more compression and boost pressure the amount is determined on if you use 12mm or 14mm head stud but it ranges normally from 70 to 100+psi boost.



Oring is the same benefit but only usaully hold 50 to 60psi boost most of the time.

Mine's fire ringed and it won't hold 45 psi. Just blew #4 since March. Yes, I have studs, and last time they were torqued to 140!

 

[cahammer]

I wonder if your studs got streched just a thought

 

[Bandit1]

are the grooves exactly all accurate, if the grooves were cut with the motor in frame the back 2 cylinders are very hard to cut and even a thou of an inch can cause probs. also are your 12mm's? there are different grades of fire rings and some aer more stiff than others and with the 12mm studs they dont crush evenly and completely. i have rings from when i had my 12mm studs and the when i had my 14's installed, there is a world of difference. food for thought, josh

 

[Jim Fulmer]

Oring is the same benefit but only usaully hold 50 to 60psi boost most of the time.

I ran a single O-Ring . 051 wire with 18 thou protrution and 12mm studs at 65-80 psi of boost for over 2 years with zero issues..... FYI!



Jim

 

[zstroken]

YOu can cut just the ring in the head or the block for fire rings. I believe some of the shops are starting to cut them in one surface. Seems to allow the engine/head to float. At least this is what one of the guys said scheid did on his engine. They cut it in the block. On my 24V the fire rings are cut in the head only. My 12V it is oringed. Oringed will hold. I had a puller tell me he held 120 psi for 3 years with his orings. He said he was retorqueing the head every chance he could though.

 

[KingS]

bluthndr mine kept blowing out I went though 5 set of rings and headgslets after 400 to 500 miles each time its sitting at terre haute at schied right now to find out why and then to be fixed.

 

[bluthndr]

bluthndr mine kept blowing out I went though 5 set of rings and headgslets after 400 to 500 miles each time its sitting at terre haute at schied right now to find out why and then to be fixed.

KingS - let me know what they end up doing. That is probably who I will get my stuff from. Last time it blew they told me I needed 14's, but I thought would try once more with the 12's since I just spent all that money for the 12mm ARP studs. The real problem is that I only did it when I upgraded my pump and turbo as a preventative maintenance thing. Never had a problem before that. Basically I spent a bunch of $ for machining and ARP studs just so I could spend another $800 in head gaskets, and pull the head off every 2 months.

are the grooves exactly all accurate, if the grooves were cut with the motor in frame the back 2 cylinders are very hard to cut and even a thou of an inch can cause probs. also are your 12mm's?

Grooves are cut in the head surface at one of the best diesel performance shops. I trust them to do the job right, 12mm ARP studs.

I wonder if your studs got streched just a thought

Could be but this is #4. First time was 120 lb/ft cold, with retorques cold. Second time same thing, Third time retorques were done to 120 hot, 4th time they were done to 140 cold. Torqued using new Snap-On 1/2 inch digital torque wrench. Gasket surface was clean enough to eat off of, and the rings fit in the groove perfect and were centered in the gasket when it was on the dowels.