Engine/Transmission (1994 - 1998) Exhaust question (and some rambling)

[CGustafson]

Howdy,



I am relatively new to turbo diesel Dodges and TDR. About a month ago I purchased a '95 2500 4x4 with 145K on the clock and engine in near stock tune - plate all the way forward and line to the turbo wastegate disconnected. That last bit troubles me a tad, but haven't had time to research it on the forums. I suspect AFC star wheel is in OEM position - no black smoke ever. Bought the truck with light bubble rust over the rear fenders and a few minor (hopefully) problems to keep the initial price of membership down to $6. 2K. Been quietly lurking around the forums since then, trying to pick up some general knowledge by osmosis.



My inaugural question on the forum relates to the exhaust.



The current set up is a home brewed 1/8" walled 4" straight pipe attached to the stock downpipe about where I gather the cat would have been (had no idea these things had a cat). The guy had good intent, but welding that heavy tube to the frame in two places was not a very well informed move. I learned not to do that when I was a kid. The entire box functions as a speaker diaphragm. Sometimes the entire truck gets into the act. Can't wait to get it replaced.





To that end, I bought a s/s Rip Rook 4" turbo back w/27" muffler after perusing the forums for recommendations. Haven't got it yet, but I'm scoping out the install. Looking at the bolts holding the down pipe clamp at the cast turbo exhaust elbow, I'd say there is about 0% chance they are going to back out of their holes. In the spirit of planning ahead I'd like to hear other folks experience with this.



The way I see it, after I spend a bunch of time trying to sweet talk them out with the torch, penetrating oil, vocabulary, etc. , I will finally snap them off. I can then either drill and retap the holes to the correct thread (which is difficult to discern right now), or I can drill them clearance for the correct bolt diameter and run the bolts right through the flange into nuts and lock washers and not have to worry about it again. I'd appreciate some informed input on this. There is not a lot of material on those flange ears and I hate to weaken them with thru holes, but if you've tried tapping heat cured iron it has the potential to be a real gut wrencher. I don't need a broken tap in one of those holes right now.





A complicating factor is that my shop was struck by lightning and burned badly in July. I'd say I'm about 1/4 of the way to recovering from that, cleanup wise, never mind rebuilding things like work benches and shelves. For instance, before I use my torches I will have to clean a thick film of greasy black goo off them and hope I can clean the gauges well enough to read them. Same applies to all my tools. Not sure where my stud remover is. No compressor to run my now rusty air hammer, a really useful tool if applied with some thought. Don't know where my anti-seize is.



Don't have a fire. It has ruled my life this entire summer, and will continue to do so. For the same reason, my responses to this forum may not always appear timely. Sorry in advance.



Any comments appreciated.



Regards, Chuck

 

[Bob4x4]

Out of the MANY exhaust systems I have installed on various year CTDs I have never snapped a down pipe bolt..... admittedly I am not in the rust belt but I have run into trucks that came from outside of Cali. Soaking with a good penetrant should get it done.

 

[CGustafson]

Thanks for your views on that Bob4x4. I don't think the Michigan climate really got up that far under the hood, so maybe your experience will apply here. I'm used to Mercedes diesels where every fastener, no matter how nasty a spot, simply threads off like it was put on yesterday.

 

[Bob4x4]

LOL you wouldn't like working on the new version of the Mercedes 3. 0. They are micro encapulating many of the engine fastners and are supposed to non reusable. Thankfully Cummins bolts are high quality and in my experience even exhaust bolts are good for many years of service

 

[CGustafson]

Heh. I probably don't have to worry about working on one of those any time soon!

 

[GAmes]

I just replaced my stock exhaust with an MBRP system. I soaked the nearly 800k mile old bolts with PB Blaster and let it sit overnight. In the morning I gave them another shot, then went under the truck with a 1/2 inch breaker bar, all my 1/2 inch extensions and the proper size socket. To my surprise, the bolts broke free with very little coaxing. I think you will be OK.

 

[CGustafson]

800K. Whoa! That's impressive miles, and this job is starting to sound not too bad. I've got a can of Kroil right where I know where it's at in the storage units and I think it's pretty similar to PB Blaster. Have to clean all the gop off of it and my extensions, but you guys give me hope I'm not going to need the drill afterall.

 

[JMcCoy]

I also installed the 4" MBRP exhaust. Great kit. No problems with the bolts. It took two or three hours, on the ground, with a friend's help. PB blaster will really help. Good luck

 

[JKosten]

You should be fine with soaking it. Just remember that your turbo is working heat into those bolts and rust every time you put it under load. When I swapped out my exhaust system it helped to have a 3 foot extension (Snap-on).

Also I would not just disconnect your vacuum line to the waste gate. The aneroid should be blocked to prevent a vacuum leak. On my truck I installed a needle valve to allow complete block-off or the ability to open it without tools if I am hauling heavy loads on the trailer.

 

[CGustafson]

I'm glad I asked this question. Getting 100% reassuring feedback. Now I'm really going to be dismayed if I do have a problem!



I figured I'd give it a good soaking when it has just cooled down enough not to evaporate the penetrating oil, then douse it some more cold. I've always been fond of giving rusty bolt heads a few careful light raps from the air hammer with a flat bit just to jar things loose and help work the oil in. You can see when you get them apart how far the oil worked down on the threads. Alas, not an option this time around.



It's interesting that these exhaust systems seem to run a good bit hotter than what I'm used to on the Mercedes, both from what I read and from the appearance of the fasteners. I have literally run the car into the garage, changed my clothes, then dropped the turbo and carried it to the bench with bare hands twenty minutes after the car was on the interstate. I suspect you wouldn't do that with a CTD.



Glad for your views on the waste gate line, although I'm puzzled by the vacuum part. I assumed that's boost pressure, or atmospheric at lowest. Either way, the port is blocked with a pipe plug currently.



Apparently, then, it isn't unusual to disconnect them. My concern is that, having no gauges, I can't see what's happening. Sounds like not an issue if I don't put a load on it from what you say. Gives me a little breathing room, but I think I'll follow your lead and install a valve. I've got to move some machine tools back to the shop pretty soon and I'll feel better if I know I'm not over boosting.

 

[JKosten]

Sorry I meant boost leak but glad you at least had a plug in it

 

[GAmes]

I'll feel better if I know I'm not over boosting.

The only way your will know that is with a gauge. They really aren't that expensive or difficult to install. Overspeeding the turbo will shorten it's life, mine lasted 750k before I installed a new one. The original had just a tad of side to side. There is some info about wastegates in this thread that might help.

https://www.turbodieselregister.com.../225655-egt-too-high-too-much-smoke-bark.html

 

[CGustafson]

I definitely plan to install gauges. I like to know what's going on and I was a bit surprised the previous owner didn't at least have a boost gauge in it, particularly since he disconnected the waste gate. I never had an EGT in the Mercedes, but the most radical modification I made to it was to jack the waste gate up from factory 10 Psi max to 11. 5 and disconnected the overpressure switch which would disable the aneroid. 11. 5 seems paltry by Cummins standards, but the Merc runs a 21. 5:1 compression ratio. Anyhow, I wasn't worried about EGT's.



Unfortunately the fire is setting my priorities currently and getting the exhaust system on is going to be the end of my recreation for awhile. Gauges will have to wait. Gives me an idea for a Christmas present though. I just need to find someone to suggest it to my wife!

 

[hsmith]

GAmes gets a lot of mileage out of his truck, turbo, injectors, etc. I know for a fact he is still on the original rear brake shoes also!!!

 

[CGustafson]

A brief hiatus in the exhaust endeavor. The folks I bought the Rip Rook from forgot to ship it. One of the dudes' father died. Bummer for all. I called on that a day or two after I figured it should have showed up. Finally got it last Friday.



Got my Kroil penetrating oil and some 6 point sockets, extensions, and such from the storage units, about a twenty minute round trip. Got home, let the exhaust cool and gave the bolts a decent soaking around the threads and under the heads. I've got a little glass syringe I use to put it just where you need it. Did it one more time before hitting the sack.



Saturday I crawled under there with about 3 feet of 1/2" extension and my good S-K ratchet, all looking black beneath a layer of fire goo. You'd think that stuff would just wipe off. Actually, it would take about five minutes for each extension, including freeing up the balls. A lot more for sockets to get all the rust and crap out of them. The ratchet I oiled up good, but the crud in the knurling is going to be a trial. Just haven't had time yet.



Anyhow, I reefed with a fair bit of force on the flange bolts, then more, and a bit more yet. I was impressed by the feel of the bolts under torque, but really didn't care to put more force on them than I did. Hmm...



Drove the truck over to the other house, the one that got struck by lightning, to heat the exhaust up, since the torches are at the storage units and may or may not work. Did some work over there and doused the turbo hardware with Kroil again just when things cooled off enough not to boil the Kroil off. Worked some more, then back to the other house and repeat the Kroil treatment, augmented with some firm tapping around the flange ears and straight up on the bolt heads. Applied more torque than I thought reasonable. No Dice. Not willing to snap them off yet, or strip the hexes. More Kroil and it's bedtime.



So yesterday, back to the storage units for my filthy torches. Searched for awhile to find my goggles. Yuck. Searched longer to find the torch tool box which has some old welding glasses. Something else that needs cleaning. Loaded it all up and hauled it home.



Kroiled things one more time, let 'em soak, then applied the torch to the problem. Got one ear up to just a slight cherry glow, then scrambled under the truck, reefed big time, and popped that sucker loose. One down. Repeat on the outboard bolt, with a U-joint and few cuss words thrown in because that one just doesn't quite let you get on it straight. Cracked it loose. I let things cool and Kroiled it all one last time. Don't need them galling in the flange with victory in sight. Spun them out and I believe that's the hard part of the job done.







I would not say that the bolts simply dropped out of their holes. I will agree that Cummins hardware is pretty impressive, though, because I put some serious torque on those babies and never felt any yield at all. The flange threads are clean, bright, and looking literally like new. The bolts are a tad oxidized, but a very light power brushing on the threads and under the heads - don't want to take that oxide off and open the material to more corrosion - has them looking plenty good for re-use.



I searched and searched for my copper and moly anti-seize with no luck. But we've got both a silver based anti-gall paste and a moly based paste where I work. The bolts will get a good thick coat of one or the other and run in and out of the flanges a few times to spread it out before I put it all back together.



I'll let folks know what I think of the Rip Rook when I get it put on, hopefully tonight.

 

[CGustafson]

Well. My estimate of when I'd be wrapping this up was optimistic. Actually finished the job Sunday morning the 14th, working on it an hour or two each night and most of Saturday.



First problem was removing the fabricated straight pipe that came on the truck. It was made out of 3/16" wall 4" tube (not 1/8" like I originally thought) and probably weighed approaching 100 pounds. It was a real bugger to get out of there.



After that, the main hurdle was the water tube that goes to the back of the transmission heat exchanger. Just couldn't get that little sucker out of the way. Tried to push it further into the rubber elbow, but that baby was pretty stiff and just didn't want to cooperate. Finally, a slight mod to the tube bracket and gentle force applied with a long 2x4 to shove the tube into the elbow while tightening the clamp gave me about 3/16" clearance on both sides of the down tube. Close, but adequate when all was said and done.



From the down tube to the muffler went pretty easy. Rip Rook (or Diamond Eye, the actual manufacturer) supplied two straight sections, maybe 48" long each, to run between the downtube and the 27" muffler. Individually, they were about 6" shy of being long enough, so I cut one such that the additional section would be 16" long, to put the clamp in a convenient spot.



The tailpipe came in two sections and it was a bit of a problem getting all the clearances acceptable and still having the outlet near a point that looked good and provided a spot to attach the last mount. I had to cut about six inches off the first tailpipe section, the one over the axle, to clear the spare tire and the frame. Then I spent quite awhile trying different positions of the two sections to have everything come out right. Finally trimmed about 3" off the second section and clamped everything down.



The final issue was the rear most mount. Due to all my welders and most of my power tools being trashed by the fire, I spent the extra $25 for a rear mount that did not require welding.



I lay on my back for a good hour total holding that thing every which way to try and make it work for me, but it never even came close. I finally went to Napa and got a universal hanger and managed to do a solid job of supporting that last section, but it has a big 4" clamp in a spot that's a little more obvious than I like. That will change when I get some fabrication capability back.



All in all, not too bad, although it took longer than I really wanted. The sound is perfect IMHO. Just enough to hear what's going on without being a nuisance. A dramatic improvement over the original straight pipe, which you may recall was welded to the frame and the OEM rear mount. Bellowed like a love sick bull with any but the slightest pressure on the throttle.

 

[GAmes]

Dang I'm glad I got the MBRP after that narrative. No cutting, everything the right length. I did the whole thing in about 2 hrs after removing the old exhaust. I had the same issue with the rear hanger though but finally figured it out (after drilling two sets of holes). I recently sent these to another member. They might help.

 

[CGustafson]

Yah, thanks for the pics GAmes. That bracket is exactly like the one I have. But I have two 4" clamps w/mating hangers attached instead of your more elegant welded hangers. What I don't have is any drawings or instructions remotely hinting how to use any of it. Your picture makes that pretty evident and I may crawl back under there and move things around. Maybe wait till I get a welder up and running and use the old hardware to attach some hangers like yours instead of the slightly cheesy clamp/hanger approach. I even recall two holes up that way that may well mate w/the bracket.



The MBRP system looks like a more refined product - slightly smoother bends, no cut installation - and you don't mention any hassles with the heat exchanger water tube so I wonder if the downpipe takes a better path through there.



But! The Rip Rook cost $452 plus $85 shipping for the T409 Vs $655 plus whatever for shipping from MBRP. Quality of the tubing, bends, and slip joints is very good. The $200 difference for the systems alone spoke pretty loud to me, and I'd probably go the same route again. I live in a Dutch area and I guess some of that ol' Dutch tightness has rubbed off on this Swede! Still, what would a good instruction sheet cost them to copy and toss in the box? That alone would have saved an hour (ultimately fruitless) of laying on my back scratching my head.



For anyone weighing the pros & cons of the two vendors, consider that I'm a super picky mutha. I'd guess most folks would have shaved 30% off my installation time because they'd have slapped things up there and clamped them down without a couple trial fits and filing all the burrs off the saw cuts, and basically wound up with as good a final result.



Recall too that removing the fabricated portion of the system took a couple of hours that wouldn't have been necessary with the OEM pipe. Sawing thru that 3/16" wall, twice, took some doing, even with the Sawzall. Probably should have gone to the hardware and bought a longer blade, but that would have been another day delay, plus more $. Just lifting that pile of steel over the rear axle and snaking it past everything took me a half hour. It was heavy enough I didn't want it grinding on the parking brake cable when moving it so I had to keep re-rigging Ancras to support it.

 

[GAmes]

The MBRP system looks like a more refined product - slightly smoother bends, no cut installation - and you don't mention any hassles with the heat exchanger water tube so I wonder if the downpipe takes a better path through there.



But! The Rip Rook cost $452 plus $85 shipping for the T409 Vs $655 plus whatever for shipping from MBRP. Quality of the tubing, bends, and slip joints is very good. The $200 difference for the systems alone spoke pretty loud to me, and I'd probably go the same route again.

I don't have a heat exchanger water tube, but the downpipe is very close to the firewall.



You may not want to hear this but the T409 MBRP kit from Genos including the bracket and shipping was $534. Shipping weight included 7 oil filters. MBRP is lifetime warranty too.



At any rate, I'm glad you defeated the bear.

 

[CGustafson]

GAmes, you're right! I don't want to hear that.



Oh well, I had a character forming experience which you were denied, not to mention getting to enjoy the great outdoors, lying on my back beneath a truck for hours. And I've got a bunch of extra 4" 409 series stainless tubing that will lie around my shop waiting for some future use, forever.



I guess you wouldn't have the heat exchanger. Didn't catch the 6 speed in your signature (envy).