Turbo Bark

[paccool]

Well, I heard my first case of turbo bark a few weeks ago. Was towing the travel trailer, had 15 or so psi of boost as I was accelerating. Someone pulled out in front of me and I got off the throttle real fast. Heard a strange noise that I'm assuming was turbo bark. Made a real sharp, almost a roaring sound. Has done it one more time since then. I'm going to assume part of the reason I never heard this before is the increased boost I now have and may also have something to do with the HX-35 turbo (maybe has tighter tolerance's?)



Question - is this"bark" harmful if it only happens now and then? What exactly is happening when it does it? I'm going to assume it is the pressure in the system coming back out the turbo end when lifting off the throttle. Saw reference to it in another forum and it sounds like it is not a good thing to have too much of.

 

[Greenleaf]

I love it!!!



Ya otta hear one of our pulling tractors when it's at the 300 foot mark and let go of the throttle lever!!



I wish I could recall the thread no. when we discussed this last. Was in October, I'm sure.



I can get my truck to do it with little effort. Usually at about the same psi, 15 or so



Scott

 

[skobylenski]

I know I've done it accelerating uphill when shifting from 3rd to 4th, and I have the dreaded 21cm still :{ I can't do it on level ground, though.



I seem to remember talk that barking, or huffing, a turbo is not a good practice, but once in a while can't hurt too much, I'd guess.



BTW - anyone want to donate a 16cm they might have lying around? I'll pay shipping, and maybe a little more if ya' want.



Another Scott

 

[sparks57]

Turbo bark is not good. You'll notice that sled pulling trucks goose the throttle right at the end of the run so the turbo does not bark.

 

[cerberusiam]

Well, with the H1C and 21 housing it would bark every time I got out of the throttle at high boost. I have to think it is not a good thing cuz the turbo went tango uniform after about 20k.



Running an HX35/16 and can't make it bark now at all. The BC meter says the truck runs better than ever with less fuel so am not sure if I have boost leaks or ???



Skobylenski, you need more fuel. Try 3 to 4 turns on the full power screw and see if it barks then.

 

[JStraw]

I've been barking the turbo for 3 years now. Primarily because I don't baby my truck. It's a work-horse... and hauls a$$ as well as heavy loads. No problemo



IMO, if I wanted a vehicle that needed TLC to keep running, it wouldn't have been the DODGE diesel.

 

[J DeMaio]

My old truck would bark with the 12 cm exhaust housing and no wastegate. It would build 28 pounds of boost It really isn't good though, it can twist a shaft.



Greenleaf: What kind of pulling tractors do you have?



John

 

[Greenleaf]

I started off with a John Deere 820 (Diesel) No turbo but really pulls well. Lots-O-Smoke!



Then got hooked up with a friend who needed some help with his rig, and because I don't have $150K to build/buy my own. This is a D21 Allis Super Stock built for the State Pulls. Three Turbos/P pump.



Currently; another friend of mine retired his Super Modified 4X4 (Chrysler) to build a pulling tractor. We have the chassis near completion and engine work is underway. Cat Power w/alcohol heads. This will be a State Super Stock puller. Three turbos. Shooting for 120psi manifold pressure.



Scott

 

[JLEONARD]

I have never heard mine bark... . I make almost daily "max boost checks" at 25- 30 psi, and then suddenly let off, and still have not heard anything.

Maybe because I have no intercooler and the air tube is short with literally no hose that the system acts differently??

Maybe I (my pump) need a couple turns??



Jay

 

[bgilbert]

I think I have this problem too, on my 89 5sp. I thought it was described as a 'cough'. The build-up of boost (pressure) then a sudden let off of the throttle and the built up pressure goes back through the turbo and out the air filter?? Ever since I installed a pair of 5" stacks I can hear this cough or bark when I wind the gears out and shift or push the clutch in quickly. It only happens when I get into it real hard-(more boost). Although I havent installed my guages yet, so I can't say how much boost (18cm stock). I figure this can't be good. Never noticed it before with stock 3 inch straight exhaust. Bill

 

[J DeMaio]

Greenleaf:



Is the guy who owns the D-21 a member of the NTPA/OSTPA? Is it the guy who owns Ross Agri Mechanics? This is the only D-21 that I've ever seen here that's a hot puller.



John

 

[dpuckett]

I've had a few make a kind of shhhuuuffttt!!! noise as I let off it. I guess it was air passing backwards through the system, or trying to. On my current truck, I have pegged the 40 psi guage several times, mainly trying to see how soon I can build it with how little smoke (it's harder than you think) with my new EDMs. BTW- they havent worked for me too well- too much smoke on the bottom end. Don's making me a new set that is a little cooler, to go with my naturally hotter running engine. So far, I've been able to hit 37 at 57mph in 5th. I have never heard this one bark, but it seems to come don slower than with teh bigger NWG housings. May have something to do with it.



Daniel

 

[soslow91]

Turbo "barking" definitely isn't a good thing when it happens the turbo is spinning at 100,000 rpms or something ridiculous like that then suddenly stops and turns around. I haven't heard of allot of people wrecking H1C's or HX35's very often but I've read this will do in an HX40 in a hurry the shaft breaks. I am pretty sure piers does something to their HX40's to make them tougher for this reason but I don't know what.

 

[Greenleaf]

J De,,,,

That tractor of which you mention,,,,

It lives in Z'ville. Goes by name of "Hoe Handle Engineering" They won the state points race this past year. Charlie Ross/Jeff Englehart. Formerly known as the "Eagle Snacks" sponsored tractor about three years ago. They really turned the tractor around.



There are more and more D21's out there than ever before. I'ts just that the no. of John Deere units out number then 3 to 1. Go figure.



Yes, We are the OSTPA. You can read about the pullers/results here..... www.OSTPA.com



Scott

 

[phillips5]

My 90 has barked every shift sence 1995 when I installed the stack. It had 95000 miles than has 500000 miles now. still ticking haul heavy all the time 35 psi. Nothing wrong with the turbo yet not sloppy not blowing oil. Remember to always let the truck idle before shutdown to alow turbo to slow down and cool down when the oil pump is not pumping oil and the turbo is wound up tight there is no lube for the turbo bushings this causes bad where for the turbo.

 

[dixdodge]

Is there any kind of repair or tune up to get rid of the turbo bark in a stock -01 24 valve HX-35 turbo Cummins? When driving (automatic trans) with heavy trailer the bark comes at upshift and nothing to do to avoid it. Thankful for answer.

 

[ProspectorTim]

Yeah, what's the answer to that one?



I just got my ATS transmission & Triplelok converter installed, and now mine barks sometimes when it upshifts or TC locks up.



I've only had the ATS in it a couple of days, and haven't towed anything with it yet.

 

[BushWakr - RIP]

Basically we're all talking about compressor stall... . the boost backs up and hits the turning compressor wheel and it wants to stall or stop rotation.

It is not a good thing in any turbo and over time will cause permature wear in the bearing(s) at the very least. In worst case situations it will shear the turbo shaft and take the turbo and possibly the IC with it.

The HX35's are a pretty tough unit. That is why you rarely hear of this condition causing catastrophic failures.

In fact the '35 shaft is the pretty much the same shaft that is in a stock '40. The problem with the '40 is the larger rotational mass of the pinwheels and the shear it causes on the shaft during stall.

Stan, that unit of yours will take some pretty good pounding before you have any trouble. If you want to look at some ideas for dealing/curing this give the shop a call and talk to Harry or Mark. In the mean time, drive it and have fun.



pastor bob... .

 

[dpuckett]

I have a friend with an 03 305/555 (maybe 04) auto that he put an Edge box on, (no gauges, though I'm leanin on him REAL hard)and he says on levels 3 & 4, it makes a weird noise when you let off the throttle. My first thought (esp with a HY and a 10cm housing) turbo bark, but I dont really know what to listen for. He said it makes kind of a woof, woof, woof noise, real fast as it winds down. Is this barking? It would make sense that a woof and a bark go together... ... .

 

[ProspectorTim]

Yeah, that sounds like it.



Mine is more like a sneeze than a bark. Stock turbo, stock air filter housing, stock exhaust. I guess my dog don't have enough "bark". LOL