I noticed a small exhaust leak on the #6 port at the Metal gasket....I soaked all bolts with PB Blaster, pulled Rubber hoses, Air take tubes, Turbo, And all 12 Stainless Steel bolts holding the Manifold on.....In all it took me around 3 hours.
Just posting because if you own a 5.9 or a 8.3 Cummins you will develop a leak at the Joint where the Manifold bolts back to the Head and if you have tools, it's a very easy job to do..
New Gaskets run around 20 bucks for the set.. Fixing to order me a set now and will post pictures of the Install... Always torque to Cummins spec on the Manifold and Turbo bolts
Cummins now uses a 2 part manifold as problems cracking. That is what I did when replacing mine.
JohnH
Should you use new bolts when you put the the exhaust manifold back on, or is that only if you remove the cylinder head? Was a source of trouble on my 8.3, to the tune of seven coach bucks, but then the monkey that worked on it replaced the bolts with stuff he got at Ace hardware.
Roland
I'm curious as to how many hours/miles you have on your FT and if you know if the manifold is original or not? My manifold had very significant shrinkage and would not have fit back onto the head when I replaced it and the gaskets.
John,
When I called Cummins to order my new manifold, they stated that the 2 piece units would not fit on my mechanical engine which was not what I was hoping to hear.
Roland,
I used new heat treated bolts from Cummins which were not cheap at about $10 each x 12 bolts.
I posted the prices here.
Exhaust Manifold Failures and Consequences (http://www.foreforums.com/index.php?topic=17580.msg146075#msg146075)
Robert, I bought the rig with 60,000 and now have 81,000/1809 hours......I'm going to measure the manifold tomorrow to see if I have any shrinkage... if so I'll just call cummins and order a new one.
The leak was not a major one, just small soot marks in the #6 and#1 areas....The truth is I knew I had a small leak and needed a excuse to try the turbo from my 8.3 on my "Modified" 1997 5.9 dodge diesel.
We also had to replace our shrunk exhaust manifold with a one-piece manifold as the two -piece was not for our engine, maybe for the ISC engine.
My exhaust manifold had shrunk 3/4". It scored the cylinder head so badly that the shop thought it may have to be replaced. Machined down OK. Was told by the Cummins shop that a leaking exhaust manifold was not unusual in diesel pushers, and one must keep an eye out for leaking.
Roland
And be careful with this!!! It is what got me into trouble, costing me a new replacement engine. One of the threated bolt holes that the manifold bolts threaded into stuck out on the side of the head and had broken off, and I had a exhaust leak there. Instead of removing the head and having a welding/machining job done, I opted for a re-manufactured head which was not warrantied. That "great deal" $465 head ended up ended up costing me almost $15,000. Had I got a Cummins re-manufactured head and had them put it on, it would have been covered under Cummins warranty!
Reading some of the post about manifolds shrinking up to a full inch is crazy to hear....I don't think mine is that bad, Just to be on the safe side for me or the next owner I'm just going to install a new one from Cummins.
Any one need a used spare manifold????
IMO, that is overkill. Keep an eye on it-- look with a flashlight for any signs of exhaust leakage (will show up as black, soot trail).
If no problem-- well, no problem.
Brett
The problem is not isolated to the 8.3s but can effect all of our rigs. I know Kent had a problem with his 6V-92TA and when we were at the Yellowstone entrance, we met another U300 that had had an exhaust manifold crack. They replaced one manifold on their Detroit two weeks earlier. In 5 years of ownership, this was the only glitch they had encountered.
Probably a good idea to take a bright light and mirror to check for any black soot deposits around each exhaust port every so often. In case of the need to change a gasket, Ken did it right on his pump with a liquid wrench type can with a wand followed by heat from a small torch before trying to force the nut/bolt. Good to repeat several times over a couple of days if necessary. If one does break off flush with the head, they can be drilled and removed with an easyout but it's a nasty job with the limited space our coaches have.
Pierce
If I found the manifold had shrunk enough that an end bolt had reached the edge of the manifold hole and had started to bend I would replace the manifold.
Good point. But, suspect it would be leaking were it that shrunk.
Here is a photo of our original shrunken exhaust manifold and the new one we had installed.
Notice the outer bolt do not line up. The rear had pulled in so much it broke the bolt. We had very little black soot, and felt no reduction in turbo power.
The most obvious sign of a problem is that bolts are leaning toward center, not straight.
Agree with Brett!
If it isn't leaking, keep using it. Just keep an eye on it.
Due to the metallurgical changes induced by the extreme temperatures, exhaust manifolds can be largely unpredictable, especially early in life. If you change any thin wall cast exhaust manifold before a visible leak or a broken stud, etc. occurs, you may well be worse off with a new manifold than you were with the old. New design and metallurgical composition, as well as casting medium, have bearing, but diesel exhaust manifolds are only part science. The rest of it has to do with how the exhaust manifold part has been used (or abused).
- "Green" (unseasoned) thin wall exhaust manifolds will shrink and warp much more than a seasoned manifold will.
- The thinner (and longer) the walls are, the more dramatic the shrinkage may be. Hence, thinner walled exhaust manifolds fail more than thicker walled heads do.
- Cummins has been fussing with the metallurgy and the design of the 8.3 exhaust manifolds for years (because they have had an uncommon share of challenges with it). Unfortunately, the older mechanical 8.3 and the newer ISC heads and manifolds are not interchangeable. Thus, mechanicals are not eligible to use the shorter, stouter, two piece exhaust manifolds.
- How a "Green" manifold is seasoned (over the first 50,000 to 75,000 miles), may be much more important than what it's newfangled design or metallurgical composition is; i.e. - a seasoned manifold's history of gentle warm-ups and cool-downs, as well as gradual operating temperature changes, and using proper heat-tempered manifold bolting, that has been properly sequenced and torqued (as well as re-torqued after run-in), so that the manifold stays properly compressed on the gasket and the longitudinal thermal stresses remain shared over its entire length, are all potentially more important than how old the original manifold is or how much the original manifold has shrunk.
[/list]FWIW,
Neal
Neals info is basic stuff in the metal world as a rule and is right. Stress the casting out when new and you pay for it.It is all in the molectual build. Same goes for the human body. Throw many curves at it and you pay later in life.
JohnH
In the early 60's when I was racing a 348 and later a 409 in the stock class we would brake a new exhaust manifold in less than a month, my father asked if I was tired of keeping Chevy afloat and said we could cure that problem, the next manifold was heat treated in a pit in the yard with 25 pounds of charcoal, we took a piece of half inch stock drilled it to match the new manifold bolted to it placed it in the pit with the now hot coals and covered it with coals and dirt, left it until the next day,took it out hung it from the cloths line pole and let it cool for 2 days, the long and short of it was I never had another on crack or break a bolt.
Update.... After reading all the helpful input, I'm going to keep my "seasoned" Manifold. I took it to the local machine shop for inspection and all came back with in spec so I had the guy resurface it so I can reinstall it.....My gaskets came in and I noticed the new ones are thicker and have more sealing area...I took some pics for show and tell.....Thanks again for all the helpful info guys
Neal, So what your saying is, once the Manifold is "Seasoned" it will no longer shrink or swell with thermal swings? Just curious
Correct-- but let's say that a seasoned iron manifold will change much less than a new one. Not sure any are "change proof".
I have never had to re-do a seasoned and resurfaced exhaust manifold. They ARE better than new.
Now, if it has "shrunk" to where the bolts won't line up, you will have to go to Plan B.
Thanks Brett...
..............agree entirely with Brett.
Neal
I remember when racers would bury new engine blocks underground for a couple of years to normalize/season the cast iron before building them.
Pierce
Ford flathead blocks spent 18 months outdoors in Detroit I understand
"(as well as re-torqued after run-in)"
Neal,
So the bolts should be checked and re-torqued every so often such as every 50K miles?
Thank you,
AL
No, you need to re-torque the exhaust manifold bolts after several heat cycles. Then they'll be fine for the duration.
I am replacing my exhaust manifold next week and wonder if you think that I should heat treat it as you said....would you do that to yours if it needed replaced? Did you bolt the manifold to a thick piece of lumber before " charcoaling " it? I would worry about warping and twisting.
thanks Pat
Just for the someone who may be tempted to reuse manifold bolts... don't do it... With all the labor of pulling a manifold spend the money for new bolts... Looking back on our diesel long haul trucks I don't recall ever pulling a manifold without having to drill out at least 1 bolt and often 2 or more. No way in hadez i'm going thru that and consider re using old bolts in finishing.
Pat, I can't say it will work with the cast iron we have today.
thanks bill;
I will just install and carefully warm up and cool a few times to season it, and make sure I warm up the engine before putting it in gear EVERY time. I ordered a used original manifold on ebay and I just hope it was seasoned well and has not shrunken. wish me luck, my first time working on a diesel.!
Put it on a long flat surface and check for warpage with a feeler gauge.
Have it surfaced at a machine shop if need be.
I think a used manifold is a bad idea. 7 years ago I had to have a broken manifold bolt fixed. As it turned out, 4 more bolts broke while removing the manifold. So the shop drilled them out and I opted for a NEW manifold which was not expensive. They put it on out of the box and installed special bolts that ran $12 each. I never re-torqued the bolts nor did the shop say anything about it. I just started it up and been driving since.
Is it possible for my 95 8.3 to be good for the long haul if no soot marks? Had valves adjusted at 115,000 and always drive her easy after start up. Cant say I let it sit and idle till all the way warm but definitely don't get to bully with the throttle.
Ugh, found both bolts missing on exhaust port nearest rear of motor/ front of coach. Manifold appears to be obviously warped. My hope is that as the manifold has shrunk down it has also bound in on both ends minimizing potential damage to the head from cold air sucking in on deceleration. Any ideas on where to find an improved manifold or is OEM as good as it gets?
Any input is most appreciated, we are planning a trip this coming weekend and not sure if I shouldn't let cross point Cummins here in Nashville tear into it. My concern with them doing the deal is whether or not they would use the same care with remaining bolts as I would.
Correction one of those missing bolts is broken off in the head.
There is no improved part from what I found when I replaced mine.
If you are in a hurry to get this done, I'd just take it to Cummins and let them worry about it, especially since some of the bolts are broken. It might cost an arm and a leg though.
I don't think that I would take it on the trip until the manifold has been replaced though.
My exhaust manifold was replaced? by PO who new squat about anything mechanical, long story. In any case the exhaust manifold shrunk 3/4". cylinder head had been cooked with exhaust gases. Cylinder head had to be removed and sent to a machine shop to be milled out. Managed to save the head. New head for my 8.3 at that time was about $4000. I would recommend a Cummins dealer for the repair. If you join the Cummins Power Club you get a 10% discount on part and labor. Here is a link to the club Home Page || Cummins Power Club - The Power To Keep You Moving (http://www.cumminspowerclub.com/)
Roland
I would only move it as far as the closest Cummins shop.
Roland
I bought a 8.3 that had had a leaking exhaust gasket. It was fixed prior to my taking delivery. The old exhaust manifold was re-installed, after lots of work to get the bolts out, and one of them being fitted with a bolt and nut solution. The ticket for the work was for lots of labor, and the gaskets and bolts. The repair worked fine, for several hundred miles. By mile maybe 700, I was down on power and the leak was at the same valve again.
The mechanic looked at the head, and in less than a minute noted the shrinkage, and suggested doing the repair with new parts. Cummins over nighted the parts for only a 10% upcharge!
The solution, that worked, was I paid for a new exhaust manifold, gaskets, bolts, seals and some more for the turbo hook up. I got to leave the coach 400 miles away, for service, drive home and back, pay for the new repair, and then head home. So for 1.7 coach bucks we have a really nice working diesel, making good power, and several thousand miles of happy miles.
Interesting, that is how some back yard
mechanic decided to replace a broken exhaust manifold bolt in my coach. It did not help that he/she/it used SAE bolts (Yes SAE bolts in METRIC threads) from Ace hardware for the rest of the exhaust manifold bolts. All done by PO.
Roland
Picking up parts tomorrow have proper easy out from snap on [not conical variety].The service writer for the local Cummins shop quoted $1700.00 labor with no more than two broken bolts, I said the almost $700.00 in parts was plenty for me. He then proceeded to send me three separate documents pertaining to everything I was about to undertake and assured me I would be fine. My research today and late last night convinces me it will be manageable. Will begin tomorrow evening and wrap up all day Thursday if necessary.
Funny how two days ago I thought I would check on the old gaskets and now am waiting on a new manifold ??? Glad I read this thread and acted when I did!
Well just got back from 500 mile trip after replacing exhaust manifold on my 5.9.
The used manifold was $240 on ebay, the seller even had it milled, which I did not expect and it looked like it was newly sandblasted, exhaust gaskets set $7 at NAPA, $7 turbo gasket cummins, new exhaust manifold bolts on ebay $22 for the set. $278 total for parts, $200 r&r labor (3.5 hrs)
SO the recap is; $478 total... parts and labor and she runs like a top now.
Thanks everyone her for your help! this forum rocks and I love my "new" 1992 u225 Foretravel! Never again I will own a gasoline powered rig!
Luckee!
$700.00 at Crosspoint Cummins . spent two hrs this afternoon with my mechanic friend . Dis assembly complete, now to tap out two bolts on rear most port sheared by shrinkage and two more that gave up the ghost on the other end when we torqued down . My friend asked why we couldn't bolt through the two upper bolts where there is room between the main body of the head and the flange of the exhaust port. I told him I couldn't really say? We've drilled through two bolts and broke our removal tap both times! :-(
Time to purchase a tap set for at least the bottom two busters although we will still try heat and thumping on them tomorrow.
If anyone knows why we can't simply ream out the upper two and add nuts and washers I would definately be curious the lower two are going to have to come out and or be tapped one way or the other.
That is what some backyard mechanic did to my exhaust manifold on my 8.3 Cummins. That was also my point of failure. Will not hold, lock washers will not help as the heat will destroy them. I suppose if you want a quick fix that you will have to redo and perhaps damage the head have at it.
Roland
Even heat treated steel? We successfully re-tapped all but one today. Maybe I'll through bolt just that one when we reassemble tomorrow with resignation that I will be having to continue to keep an eye on it. Will consider one last attempt at oversize tapping the last one. Frankly I am sick of it and having our beautiful old coach in this much disarray!
Thanks for the response !
Helicoil/new manifold/ARP hardware. Torque it.. one time. walk away.
Every time it is started, allow it to warm up for a reasonable period of time and shut down in the same fashion.
Personally, I wait until the feed hose on mine gets cool to the touch before shutting down.
Your turbo will last for a very long time too. pc
Nut and bolt repair is nothing I am terribly proud of . Will be much more confident when I revisit this area. My mechanic friend wants me to consider another insert method in the future. Ran for twenty minutes [around 160degrees] no leaks. Will definitely keep an eye on it for next couple trips, at which time we will tear down thermostat housing, cooling system and insert at nut and bolt and possibly one other that is suspect.
I feel strongly that vigilance both in operating procedure and watching for changes in boost will avoid any major catastrophe.
Nit and bolt repair on an exhaust manifold would be a deal breaker for me if I were buying a coach. Got caught once never again.
Roland
Its a 1 or 2 thousand mile deal for us. I took your advise to heart and will remove the thermostat/coolant filter assy. in coming months then install Helicoil or similar at nut and bolt and one other hole we re threaded. Old Trucker said the boost gauge is best tool for detecting any leaks before any scorching can occur. At this point the fact we didn't outright break the head is a victory from my perspective. Fired right up, no clacking nor visual evidence of any leaks.
Also pleased that head showed no signs of scorching from previous bolt issues. The fact remains that having traveled untold thousands of miles with two broken bolts at same port without damage is a true blessing.
Thanks for all your responses.
repaired many many bad threads in Deltic Diesel Engines in England with Helicoil inserts and other applications. never (that I know of) any issues and these engines pumped out mega HP.
I seem to recolect also using them in Helicopter rebuild situations (Sundstrand).
They were all we used in the 60's.
JohnH
Timeserts are oem line repairs for gm and Chrysler for damaged holes.
Bob..
I have a complete Helicoil repair kit.
Used it for decades without issue.
(Never buy a used manifold for a diesel!) pc
Then use it.....
Just saying technology is changing. Look at the Timesert itself. Solid sleeve versus threads only. Not saying yours does not work but my tap R&D,oval guy only uses Timeserts.
Jerry's broken tap and die removal. Santa Ana, ca. I donate occasionally to him.
Excellent transition from the Helicoil..
Thanks for the suggestion. pc
Threaded inserts are the new awesome. Various different brands, but all are pretty dang good.
Actually, not so new.
Used them in the early 1970's on 1968- 1970 VW air cooled cases. They used a soft alloy and the head studs pulled out. We overdrilled the holes in the case, tapped and installed what we called "case savers". Nothing more than inserts. But, they more than doubled the area over which the force was applied-- it was a permanent fix.
So the timesert is the more sure thing when we revisit?
By the way, drove 300 miles this weekend with no issue. boost pressure held at 25 psi max at end of trip.
I am on the verge of removing radiator and going through cooling and air system back to manifold. New cooling fans then opening up exhaust with larger resonator type stainless deal. Muffler back is showing its age!
Our Cummins exhaust manifold repair for broken studs involved drilling and KeenSerts which have locking tabs that keep it from rotating after installation. Keensert install tool is used.
Threaded Inserts from Aircraft Fasteners International (http://www.aircraftfast.com/keensert-inserts.htm)