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Topic: 94 cummins 8.3M, black circle on engine compartment door (Read 888 times) previous topic - next topic

94 cummins 8.3M, black circle on engine compartment door

Just 400miles from home..

I found this... then flashed to 2010-Jupiters red spot monolith eating my engine :thumbsdown:

Re: 94 cummins 8.3M, black circle on engine compartment door

Reply #1 –
Oil on your finger or exaust soot?

Re: 94 cummins 8.3M, black circle on engine compartment door

Reply #2 –
That is very concentrated.  Have you located the source?

Re: 94 cummins 8.3M, black circle on engine compartment door

Reply #3 –
Last boost was 28# in 6th, no issue

Soot...

I took this pic of engine

Re: 94 cummins 8.3M, black circle on engine compartment door

Reply #4 –
Oops

Left side of valve cover black...soot

Re: 94 cummins 8.3M, black circle on engine compartment door

Reply #5 –
A good shot of your exhaust leak.  You will need to pull the exhaust manifold to fix it.

Re: 94 cummins 8.3M, black circle on engine compartment door

Reply #6 –
Brett, is that a big deal?  Did I do that going down a hill, or up a hill?

Is there a link explaining it

Re: 94 cummins 8.3M, black circle on engine compartment door

Reply #7 –
Not sure we can reconstruct what caused the exhaust manifold to head union to leak.

It happens.

Only danger in continuing to drive with the leak is the increased chance of eroding the head/exhaust manifold, particularly at high throttle/high heat conditions.

Were it me, I would continue home, but take it easy and accept the small risk of increased damage.

Anything you can do to lessen the EGT's is a good thing.  For example, if a heavy toad, and second driver, don't tow it.  If flat route is a little longer, probably better than a shorter one with mountain grades.

Re: 94 cummins 8.3M, black circle on engine compartment door

Reply #8 –
Common. Look for a stainless  MLS gasket for it. Prick punch that area  a bit and install the new one.
  Spray the nuts, shortly after you park, holding a fire ext. 

Re: 94 cummins 8.3M, black circle on engine compartment door

Reply #9 –
If you have someone else fo the job, don't let them ruin the bolts holding the turbo onto the exhaust manifold. Don't ask me how I know. Cummins don't give those exhaust manifolds away cheap.

Larry

Re: 94 cummins 8.3M, black circle on engine compartment door

Reply #10 –
Yup, the right way is to take your time, plenty of good penetrating oil, heat, sharp raps-- what ever it takes to GENTLY get it disassembled.

If at home where you have time, soak for a  week with a good penetrating oil before even thinking about starting.

Re: 94 cummins 8.3M, black circle on engine compartment door

Reply #11 –
Not saying the Banks caused the problem but more horsepower = more heat.

Re: 94 cummins 8.3M, black circle on engine compartment door

Reply #12 –
I did mine back in July.  Parts from Cummins ran about $250 +/- and labor ran $590.00, at an independent truck shop.  3 of 12 bolts broke off and were drilled out.  Engine number to your Cummins part guy and he'll fix you right up.  I priced a new exhaust manifold in case mine was not reusable and it was $265.00.  Luckily mine was OK.  Don't run too long like that.  Getting home 400 miles should be OK.

jk

Re: 94 cummins 8.3M, black circle on engine compartment door

Reply #13 –
Upgrade to the ATS, 2 piece exhaust manifold and it will never be a problem again

Re: 94 cummins 8.3M, black circle on engine compartment door

Reply #15 –
Quote from: Jack L –
I do not see ATS two piece, made for, or for sale for 8.3.

When I priced out the original for my 8.3, IIRC the Cummins parts man said it was not available for my serial number. 

YMMV

jk

Re: 94 cummins 8.3M, black circle on engine compartment door

Reply #18 –
Unfortunately, it looks like the listing is for the ISC 24 valve engines;
Don
Quote from: Pierce & Gaylie Stewart –
Cummins 8.3 two piece manifold from China for $281 delivered: Exhaust Manifold 3967751 +3937478 for Cummins ISC 8.3L 300HP 4B3.9 QSB5.9...

It's usually 10 to 14 day shipping to our house.



Pierce

Re: 94 cummins 8.3M, black circle on engine compartment door

Reply #19 –
Kimosabe, it must be the difference between the 8.3 and the M-11. Cummins couldn't get all 3 pieces for my exhaust. Only had 1 end and the middle. It was over $1250 for the parts alone. I drove the 150 miles to Amarillo and picked them up. The labor for this part of my repair wasn't broken down, so I can't say how much it was. Just know that if I had to do it over again, I would have bought the tools on my trip, did the repair myself, and given the tools away and I would have been a few thousand dollars ahead.

Larry