pre-combustion chambers

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Mar 30, 2006 | 03:56 PM

sosotwo

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pre-combustion chambers

I picked up a used 6.9 to replace the one in my truck.
I figured I should pull the heads to see how every thing looked to my suprise there is no pre combustion chambers in it??
whould that run right?
it sure don,t look right to me it looks like it burn't part of the head gasket and maybe bypassing antifreeze.
Is it good or bad to run like this?

Mar 30, 2006 | 04:50 PM

bilder12

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From: Northeastern Pa - USA

the pre cup chambers are part of the head. If they arent in the heads, there shoudl be one helluva hole per cylinder in the heads. I doubt if they will run without the chambers. Sounds like ya got to get the heads checked too, if it has symptoms of blown headgaskets.

Mar 30, 2006 | 05:45 PM

PLC7.3

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Joined: Nov 2004

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From: Manitoba

Yes they will run but smoke like hell, the lack of the Pre cups means there was no real combustion chamber seal to the cylinder. The pre cups seal the top half of the head gasket area of the fire ring. Cracks in the precups beyond the fire ring is usually bad enough to cause problems, missing completely is way..way out there.........

I would say as above get the heads checked over and get new precups.. get this done by a AERA associated shop. There are special instructions for the precup to head levels and max/minimums on the head refacing. Need more email me........