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Topic: 94 cummins 8.3M, black circle on engine compartment door (Read 746 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:
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My advice and experiences are Free, you decide if they are worth anything .

John - driving Old Faithful
1994 U280 GV
C8.3, Banks, Pacbrake, 900 watts, Resonator, XLHD tow dolly
Retired Army Warrant Officer

Life is what you make of it - if it is lemons, make lemonade!
Former Coaches:
1988 GV 40' ORED 300HP CAT - 9 years
1990 Winnebago LeSharo - 3 years
2000 Newmar London Aire - 3 years (#18 of 23 produced)

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

Reply #1
Oil on your finger or exaust soot?
Dub McBride 1996 270

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

Reply #2
That is very concentrated.  Have you located the source?
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

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
The selected media item is not currently available.
My advice and experiences are Free, you decide if they are worth anything .

John - driving Old Faithful
1994 U280 GV
C8.3, Banks, Pacbrake, 900 watts, Resonator, XLHD tow dolly
Retired Army Warrant Officer

Life is what you make of it - if it is lemons, make lemonade!
Former Coaches:
1988 GV 40' ORED 300HP CAT - 9 years
1990 Winnebago LeSharo - 3 years
2000 Newmar London Aire - 3 years (#18 of 23 produced)

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

Reply #4
Oops

Left side of valve cover black...soot
The selected media item is not currently available.
My advice and experiences are Free, you decide if they are worth anything .

John - driving Old Faithful
1994 U280 GV
C8.3, Banks, Pacbrake, 900 watts, Resonator, XLHD tow dolly
Retired Army Warrant Officer

Life is what you make of it - if it is lemons, make lemonade!
Former Coaches:
1988 GV 40' ORED 300HP CAT - 9 years
1990 Winnebago LeSharo - 3 years
2000 Newmar London Aire - 3 years (#18 of 23 produced)

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.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

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
The selected media item is not currently available.
My advice and experiences are Free, you decide if they are worth anything .

John - driving Old Faithful
1994 U280 GV
C8.3, Banks, Pacbrake, 900 watts, Resonator, XLHD tow dolly
Retired Army Warrant Officer

Life is what you make of it - if it is lemons, make lemonade!
Former Coaches:
1988 GV 40' ORED 300HP CAT - 9 years
1990 Winnebago LeSharo - 3 years
2000 Newmar London Aire - 3 years (#18 of 23 produced)

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.

Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

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
Larry Warren
1996  U320 36' SBID "Lola" sold 2020
Build #4970
Motorcade #18318

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.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

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.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

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
Jack and Cathy
1992 U280 Unihome 36' Build #4034
Cummins 8.3 /  Allison MT647/ PacBrake
Apopka, FL / Barre Center, NY

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
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.

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

Reply #14
Upgrade to the ATS, 2 piece exhaust manifold and it will never be a problem again

I do not see ATS two piece, made for, or for sale for 8.3.
97 U295 40, Build #5040, 6C8.3 325 HP
Oregon Continuous Traveler
Samsung Residential #RF20HFENBSR,
Xantrex SW2012, (3)AGM8D Hse, (2)AGM Grp24 Eng, Victron BMV-712, 1800w Solar 4 LG & 2 Sunpower
Extreme Full Body Pt w/hdlmps, new furn/floor, 4 down Lexus 2004 GX470 AWD curb weight 4,740 lbs
Prev: 1990 Barth, 10L 300 2 yrs; 91&92 Monaco Signature, 10 yrs, 10L C 300 &  6C8.3 300; 1997 ForeT 6C8.3 325 since May 2017.  Employed by Guaranty RV 14+ yrs.  Former VW New Car Dlr/Service Dlr, Sales Mgr, Rv Sales, and Service Adviser from 1968-2017
"Don't criticize what you can't understand" Bob Dylan

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

Reply #15
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
Jack and Cathy
1992 U280 Unihome 36' Build #4034
Cummins 8.3 /  Allison MT647/ PacBrake
Apopka, FL / Barre Center, NY


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

Reply #17
A good shot of your exhaust leak.  You will need to pull the exhaust manifold to fix it.
And turbo.
1994 U280, Build 4490
Deming, NM.

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
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
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Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson

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
Larry Warren
1996  U320 36' SBID "Lola" sold 2020
Build #4970
Motorcade #18318

 

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

Reply #20
I did watch Temps an down shifted when in yellow. Most of time up hil I let the Allison do its thing.


Thanks for in site and part numbers...
The selected media item is not currently available.
My advice and experiences are Free, you decide if they are worth anything .

John - driving Old Faithful
1994 U280 GV
C8.3, Banks, Pacbrake, 900 watts, Resonator, XLHD tow dolly
Retired Army Warrant Officer

Life is what you make of it - if it is lemons, make lemonade!
Former Coaches:
1988 GV 40' ORED 300HP CAT - 9 years
1990 Winnebago LeSharo - 3 years
2000 Newmar London Aire - 3 years (#18 of 23 produced)