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Exhaust manifold

The exhaust manifold on my ISC 8.3 is leaking at #4 cylinder and broken all the way around at 2and3. Boost is still 22-23 lbs a full throttle. Question is will it cause damage ( cylinder head, pistons)  to drive it 700 miles or so, where I can do the work myself, or 200 miles where I can drop it off where I can leave it for 2-3 weeks and they will " work it in" I have used the folks before, but who knows?

Re: Exhaust manifold

Reply #1 –
Diesels have no vacuum unlike a gas engine which might suck in cold air and warp a valve. I wouldn't hesitate to drive it home but DWMYH

Re: Exhaust manifold

Reply #2 –

Not good. The escaping gas can cut/erode into base metal and the leaking exhaust can damage anything it comes in contact with. I would always recommend repairing. If it was my personal rig I might cover crack with stainless and secure in place with band clamps. There may be a hi temperature epoxy but it's going to fail. Also any additional heat shielding will help. Sorry to hear this. Lower power setting will help. Factory replacement parts for me. Once all bolts are removed tap out to clean threads and I would use good nickel anti seize during assembly. A lot can be lost in attempting to baby it back home. Good luck  Be safe
Scott
How many miles on that header and is it one piece?
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Re: Exhaust manifold

Reply #3 –
I had a similar experience that went undetected for a good 1000 miles on an ISL400.  Both of the above comments are accurate in my experience.  My performance wasn't noticeably affected except in retrospect... a very slight loss of mpg and boost.  What did suffer were a number of plastic electrical and mechanical components in the engine compartment from the escaping hot gas.  If you can get the hot gas leak controlled, then I wouldn't hesitate to drive it a longer distance.  Shielding is a great help, but just the general increase in compartment temperature melted a number of wires and relays remote from direct exhaust gas flow.  No failures but a "wilted" appearance.  I ultimately replaced a lot of items.  If you cannot control the HEAT, then I'd favor tearing it down and replacing the manifold ASAP.  You could try and get the heat mitigated, and check engine room spots every couple of hours in route with an IR temp gun.  Just get a baseline established for the spots you're checking after you're satisfied the leak is as good as you can get it.  Shielding, exhaust heat wrap with stainless clamps, heat resistant epoxy and frequent checks will probably get you to your destination safely.  You are way ahead of me having identified the problem early.  Mine cooked unmitigated for over 1000 miles.  I used a Cummins replacement manifold FWIW. 

Re: Exhaust manifold

Reply #4 –
Agree with Hach about the heat,not sure how it will erode something other then the manifold that's already broken,if you can figure out how to keep the heat down go for it,you will do a better and less expensive job yourself.Now may also be the time to replace the turbo as it will have to be removed.

Re: Exhaust manifold

Reply #5 –
Bruce,

Do you have any idea as to how far you have driven with it like this? If you have to drive 200 miles to a repair shop if you can control the heat with some heat shields I would ease on the other 500 so I could DIY.  A pair of tin snips, a couple of soup cans, and bailing wire will make a rustic hot gas redirector.

Mike

Re: Exhaust manifold

Reply #7 –
2-3 weeks? The Mexicans in Mazatlan did mine in  5 hours and 500 bucks. Just sayin.

Re: Exhaust manifold

Reply #8 –
Looks like the JB weld repair tape and on to where I will replace the manifold.

Re: Exhaust manifold

Reply #9 –
Quote from: bbeane –
Looks like the JB weld repair tape and on to where I will replace the manifold.
Please post how it works out. I dont have a lot of faith in it but worth a try. Make a few extra inspection stops. I carry a large halon fire extinguisher.
Scott

Re: Exhaust manifold

Reply #10 –
With all the trouble 8.3 exhaust manifolds have, you would think someone would cast up a modern manifold or make it in 2 or 3 pieces like others do so it can expand without cracking or bending the studs.  Here is what a one piece big diesel manifold should look like.

Pierce

Re: Exhaust manifold

Reply #11 –
My manifold is 2 piece.  It does seem like today's world manifolds could be made to not warp and crack.

Re: Exhaust manifold

Reply #12 –
Quote from: Pierce & Gaylie Stewart –
With all the trouble 8.3 exhaust manifolds have, you would think someone would cast up a modern manifold or make it in 2 or 3 pieces like others do so it can expand without cracking or bending the studs.  Here is what a one piece big diesel manifold should look like.

Pierce
Sure like the ISM better. Same bolt fatiguing issues unfortunately.
Photo 2 is of the ISX even better

Re: Exhaust manifold

Reply #13 –
Scott,

The manifold foto I posted does not have any holes for studs, just a space for a stud and big washer to take the expansion between each cylinder. Cummings probably should have gone horizontal with the studs rather than vertical.

How about stainless studs with no-seize?

Pierce

Re: Exhaust manifold

Reply #14 –
My ISM has horizontal studs. Not sure I have ever seen vertical studs on a diesel

Re: Exhaust manifold

Reply #15 –
Quote from: Pierce & Gaylie Stewart –
Scott,

How about stainless studs with no-seize?

Pierce
Hate Stainless bolts. Too many severe heat cycles. They become softer and gaule. Good hi carbon steel and good nickel anti seize. Yes the bolts on the turbo will be quite difficult to remove at end of life, but they are still there doing their job. Ive changed hundreds of turbo chargers with 1600 hours to 2600 hours and there is a difference with the added 1000 hours. Bolt head will reduce in size from erosion and heat cycles. Never once did I have to torch off a bolt but wanted too several times. Did split many a nut to relax enough to remove. Hard pull on our long grades and these components go from 400 degrees to upward of 1700 in isolated areas. Hard pass on the stainless for me.

Re: Exhaust manifold

Reply #16 –
Lots of different formulations for stainless out there and lots of stainless kits available.  In checking on several forums, many have your opinion and the other half love them. I do know Mercedes has used all stainless manifolds including the rest of the exhaust system including the fasteners for holding everything together for many years in their gasoline cars. My old 300SD diesel has cast iron but everything else is stainless. I've never seen a problem on any part of a Mercedes exhaust system except for cat failures.

Pierce

Re: Exhaust manifold

Reply #17 –
Quote from: Pierce & Gaylie Stewart –
Lots of different formulations for stainless out there and lots of stainless kits available.  In checking on several forums, many have your opinion and the other half love them. I do know Mercedes has used all stainless manifolds including the rest of the exhaust system including the fasteners for holding everything together for many years in their gasoline cars. My old 300SD diesel has cast iron but everything else is stainless. I've never seen a problem on any part of a Mercedes exhaust system except for cat failures.

Pierce
I agree to install what the manufacturer engineered for their application. Odd they would be using Caterpillar  parts on it and have them fail. Guess this is why I've always stayed away from Mercedes and Caterpillar products. DWMYH. If it stays together till overhaul that is all i ask. Ive been meaning to order a set of hardware for my exhaust just to time change and upgrade anti seize. Will plan for it for next winter.
Getting back on subject,
Bruce if you can also get some Kroil or even better mouse milk and start the soaking process it will aid in removal. Especially the broken off bolts.

Amazon.com: Mouse Milk Oil 8 Oz : Grocery & Gourmet Food

Scott
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Re: Exhaust manifold

Reply #18 –
Think Pierce meant catalytic converter not Cat part.

Re: Exhaust manifold

Reply #19 –
MBZ engines and transmissions are pretty bulletproof. Almost 450K on our 300SD and never been apart including the water pump and alternator. Just several batteries and lots of brake pads. The ML 5 and 7 speeds are arguably seen as the best ever auto trans made and found on some Jeep 4WD products and others. The electrics in general are not up to Toyota standards, especially on the Alabama vehicles. Bosch alternators are also great. Single wire and to change brushes, regulator and diodes all in one tiny unit.  You just need a flat bladed screwdriver and don't even have to loosen the drive belt. A two minute change to get everything R&R.

CAT has made a lot of good engines. The parts just cost a lot. As I remember, as Progress Rail, CAT controls EMD (railroad diesels) with the ultra reliable EMD-710 engine used all around the world. EMD 710 - Wikipedia

Pierce