V-Band clamp Exhaust Leak??

[archer2500]

Has anyone else noticed what sounds like an exhaust leak from their 04. 5 or up?

I have an 05, and since break-in and even after having my exhaust brake installed I have noticed a noise from the engine compartment, specifically when I am next to something that reflects my engine noises back at me; IE a building or in an underpass the noise sounds like a small exuahst leak its nothing more than a ticking really, like the manifold may not be properly seated or a V-Band clamp might not holding the two mating surfaces completely flush. But it drives me nutts, and if it IS an ehaust leak I want to find it and take care of it rather than risk eventually damaging someting from hot gasses escaping from somewhere they arent supposed to be.

Honestly I am just not sure what I am hearing, but my instincts tell me its an exhaust leak.

I was just wondering if anyone else has had this problem or has heard the same thing. I had a 2000 CTD and never noticed this although the 2nd gens were considerably louder than the 3rd gens.

I have taked it to the dealer a couple of times and he says it's a "normal diesel noise" but I was raised on a farm and have been around diesels my whole life (I have owned 2 CTD's and my Dad had one and now has a Duramax) and this really sounds like a leak, just like if there were a pinhole (in an older exhaust system) or like something is just not tightened or seated fully.

I have felt around the down pipe and around the turbo with the engine at idle and have found nothing. I am thinking about using soapy water to look for bubbles, like with a suspected punctured tire. But obviously, once the engine begins to produce enough heat this will just evaporate and wont provide any useful results.

Does anyone have thoughts or a similar experience or am I just being too overprotective of my new truck?

 

[jelag]

You need to give this some attention... . The clamp needs to be checked at least once after your exhaust brake installation... . We tell our customers who install PacBrakes to support the exhaust and tap on the clamp with a small hammer to make sure its seated, and than retighten it.....



Its common for them to leak some after a new installation. . and you won't get great performance from an exhaust brake if the clamp doesn't seal... .



Jim / A PacBrake Distributor...

 

[archer2500]

jelag,

Thanks for the info! Should I completely break torque on the clamp first or just take the weight off it and rap it then put a wrench on it to make sure its fully seated?

The guys at Mid-States Cummins werent exactly what I was expecting given that I was dealing with Cummins directly. They didnt mention anything about checking torque on it after a break-in period or anything, I found that odd and even asked if there was any follow-up maint I needed to do. I will give it a try tonight when I get home. Thanks!

 

[RockinJ]

What I first thought was an exhaust leak in the engine compartment of my '05 + newly installed Jake Brake is actually a ticking noise from the Jake's belt-driven vacuum pump. The engine did NOT exhibit this noise prior to the Jake's installation. It ticks regardless of whether or not the Jake is operating.



Regarding exhaust leakage, the coated steel shim gasket between the turbo and the Jake is quite delicate and is very easily compromised during installation (I should know, I messed one up during my install and had to buy a $32. 00 replacement - OUCH!) Took my time and installed the replacement gasket without incident. I then checked the v-clamp connections with the Jake both engaged and disengaged - - - no evidence of exhaust leaks so far.



Just my $. 02.

 

[jelag]

RockinJ has a good point... . the PacBrake doesn't use a gasket..... I have also seen one or two installations where the clamp wasn't fully installed correctly on the back side...



These are two machined surfaces that go together and need to be clamped tightly... one the engine starts the heat and expansion of the parts should seal them completely. . and there is some stretch in the new clamp... .



If you have the Jacobs make sure the gasket is in correctly, but in either case, we support the exhaust... . thus taking the weight off the clamp... . tap the clamp to seat it better. . and than tighten the bolt... . being carefull not to breake the bolt... . something we've done a time or two... .



Where we notice the problem first... . we're all hard of hearing here... . is going down hill with a load and we don't get the right performance from the exhaust brake... .



Hope this has helped... .



Jim @ Pacific Clutch

 

[archer2500]

RockinJ I have wondered if it was the vacuum pump or not, I noticed the other day it makes a ticking noise on its own. If it were the shim, how would I tell? Would there be performance issue or some other secondary symptom?

I am going to get under the truck tonight and check the V-band clamp as Jelag suggested. I will see what I find tonight.

Thanks for the info guys!



on a side note, I am a helicopter mechanic in the Marines, and I was talking to an engine mech one day about a white residue I noticed along the seam where the compressor section of one of my gas turbine engines was bolted together. I was worried it was corrosion, he said that they actually use "milk of magnesia" when they assemble engines. They put a film along the mating surfaces, and the first time the engine is fired up, it heats the stuff, and as it boils away it makes a film/residue along the mating surfaces that helps seal small gas leaks. I always thought that was cool but dont know if it would be effective on something with such low exhaust temps and pressures as a diesel (comparatively speaking). Anyone heard about that before?

 

[MacHaggis]

Just to reinforce what you've already been told, the vacuum pump will tick, that gasket is some wicked fragile (My kit from Cummins was short the gasket and I, too, had the first one flake apart on me, necessitating a second one. :{ ) and rechecking the seat of the clamps and tapping them is a good idea.



In my own ordeal, I was FINALLY able to track down the part no. for the front clamp that will accommodate the turbo and brake flanges with the gasket. Mopar #52103596AC. It's enough wider and higher in the arch than the original clamp on the dry fit to do the job. IF you do have to redo things, I'd suggest fitting the clamp to the brake while you've got it on the bench. You'll have to twist it to clear/get under the actuator mount -- there isn't enough clearance to get it on properly with the brake up in place.



Mine is an 03, so the brake will operate at idle regardless of engine temp, and I hear the hiss any time I'm idling. I've run my hand around the joints at both ends of the brake housing any number of times and can't detect any leak around the clamps. When I'm in the driver's seat, the noise I have sounds like it could be coming from around the clamps, but when I get out and stick my head into the wheel well to feel around the clamps, it turns out it's actually the hiss from the end of the exhaust pipe. Takes some gettin' used to.

 

[tkerrigan]

As long as we are talking about v-band clamps, maybe somebody can help me with this. I installed a BD 4" inline e-brake, many problems to get it right, mostly due to the fact that the factory header pipe isn't round. I can only get up to 35 PSI exhuast backpressure now. Should be able to get to 60 PSI. I think that due to taking the header pipe off so many times I wore out the v-band clamp. Is the stock v-band clamp the best sealing clamp to install, or does anybody know of an aftermarket that would seal tighter. Thanks

 

[jelag]

When we broke one... we couldn't find the stock clamp from another vendor than the dealer... a call to cummins found that they don't stock it... . as its part of the dealer supplied items. . We offer PacBrake and they have them..... but it was 2 days away so we just went out and bought one from the dealer... .



On the side bar """ he said that they actually use "milk of magnesia" when they assemble engines""" I have a first cousin who does repairs for a logger in Asia... he spends 6 weeks working 12/7 and 6 weeks at home..... and that's about all he works on... . I'll fire off and e-mail and hope he doesn't laugh his A** off at me..... as I think someone is feeding you a line..... but, the comment sure put a smile on my face this afternoon... as I don't have a clue.....



Jim @ Pacific Clutch

 

[tkerrigan]

Jim, does the 'Pacbrake clamp' clamp any tighter than the stock clamp? Is there a torque rating for the nut on the clamp? My clamp is so streched that I have to use a 1/2" drive 7/16" long socket to tighten the nut.