Got turbo issues

[dhjunkie]

I've been battling tubo issues for my last two trips pulling my toyhauler. The turbo cuts out on climbs to zero boost, tons of black smoke out the tailpipe and skyrocketing EGT's when the boost goes away. To top it all off it is intermittant, meaning once the engine cools a bit, it'll come back and then go away again.
I am running basically a stock engine,with the HDP balance flow,97 cooling upgrades,kennedy aggresive tow chip,kennedy hi-pop injectors,ip replaced about 3 years ago,new timing chain/gears,4" exh and 2 1/2" crossover full guages trans/egt/boost, 141k miles. in process of building the intercooler.
Checked the vacuum pump; 25-26# at idle, almost 30# at 2700rpm. replaced solinoid after first show up with factory GM unit. Checker vacuum actuator pot, holds 26# for over 10 minutes.
pulled off air intake tube and think turbo fins may be worn out and what looks like a lot of blowby from the CDR tube (replaced on last trip) and oil fill tube.
Also I am throwing no codes or SES lights when the problem occurs, on this last trip I hooked up my strap-on scanner to see what the IAT was reading. right before shutdown while operation the IAT was reading 272*, outside temps were around 40-45*.

I am stumped on this, any help or guidance will be appreciated.

 

[dhjunkie]

oops, pictures too big

more pictures

 

[ak diesel driver]

possible cracked vacuum tubing

 

[ak diesel driver]

also is there slop on the turbo?

 

[dhjunkie]

possible cracked vacuum tubing

checked the tubing with a mityvac tool, no leaks

 

[dhjunkie]

also is there slop on the turbo?

define slop? I cant pull or push the impeller bolt any, but can move it up an down a little bit. these things ride on oil pressure right, so a little play is expected.

 

[ak diesel driver]

Did you wiggle the tubing while you had vacuum on it? Sometimes temp and vibrations can open up a crack that normally won't leak. As far as slop I don't have any specs but I rebuilt mine when it got to about 1/16" of side to side slop.

 

[dhjunkie]

yes, did the wiggle test and also checked while hot (after a short road trip to dump trailer tanks). are the turbo inlet blades supposed to have the cutouts? Just ran out and could get close to 1/16" of side to side play. no scraping of the shell walls though.

 

[Gulfsurfer]

just a month ago, I posted about my similar probs. Turned out to be wiring to the WG soln valve. right at the connector, check it.

All gone now though, installed a TurboMaster a couple of days ago. project thread coming.

 

[nvmtnlion]

Gawd is that WEAR on the impeller? Mine don't look like that at all.. which turbo is that?

 

[Turbine Doc]

Gawd is that WEAR on the impeller? Mine don't look like that at all.. which turbo is that?

X2-3-4-5-6-7-8.............. that a GM turbo ??? if so it's toast what have you been feeding it, been that way whole time you owned it, somebody try to do a custom trim for you on the compresor wheel it looks to uniform to be a wear issue but could be wear I guess, 272 IAT at what boost pressure ?

 

[WarWagon]

:iamwithstupid:
I thought the same thing on seeing your turbo pic. What did the turbo eat?

 

[dhjunkie]

I tightened up the WG plug sockets when I replaced the solinoid, but I'll check it again (easynuf).
As for the turbo it is a stocker GM-4 I think (whatever came in '95) the tag is shot. No customizing, I thought it didn't look right.
I bought it second hand from Washington/Oregon border area and it was in great shape for an E-bay buy (never really looked at the turbo fins), I do a lot of back country wheeling and religeously change out the airfilter as to keep the nastys at bay. I am guessing it is all of the fine silt that the filter is having a hard time filting and letting it go by.
Can a air compressor cavitate?

 

[dhjunkie]

272 IAT at what boost pressure ?

272 IAT was at 12 psi boost @ 4000k elevation in a 5% grade. The Kennedy chip will let it run at 15psi, that seems to be the limit for the 5k elevations for now, haven't taken the new chip to the sierras yet.

 

[Turbine Doc]

If you have that kind of erosion on the compressor wheel the same stuff being injested in the engine, what kind of air filter you using, I suspect you are defueling on high IAT exacerbated by worn out compressor wheel not pumping enough air,

You ever pull a oil sample to see how much silica you have in your oil, that is some pretty major erosion you have going there, only time I used to see that kind of wear was on turbines operating in desert I suspect you may be going into some sort of compressor stall with that when you are at power as well

Have you run with vac gauge teed into the wg actuator diphragm while driving, possibly you are losing vac at speed letting wg come open ?, also I had one with a slow leak in the diphragm bellows that would not hold WG shut and I could not develop full boost

Odd you can make boost then lose it, but one thing for sure that turbo is in need of replacement. I'd get with one of our oil techophile vendors and get me a oil sample kit pronto, if your air filter is letting enough stuff to whittle away your compressor, there are other engine parts it's working on as well.

 

[saturntech95]

The vaccume systems on these seem to be utter failures. I would just install a new turbo with a turbomaster. Or if you tow and climb hils alot I have heard great things about the ATT (A-team turbo) for that kinda stuff.

 

[dhjunkie]

If you have that kind of erosion on the compressor wheel the same stuff being injested in the engine, what kind of air filter you using, I suspect you are defueling on high IAT exacerbated by worn out compressor wheel not pumping enough air,

You ever pull a oil sample to see how much silica you have in your oil, that is some pretty major erosion you have going there, only time I used to see that kind of wear was on turbines operating in desert I suspect you may be going into some sort of compressor stall with that when you are at power as well

Have you run with vac gauge teed into the wg actuator diphragm while driving, possibly you are losing vac at speed letting wg come open ?, also I had one with a slow leak in the diphragm bellows that would not hold WG shut and I could not develop full boost

Odd you can make boost then lose it, but one thing for sure that turbo is in need of replacement. I'd get with one of our oil techophile vendors and get me a oil sample kit pronto, if your air filter is letting enough stuff to whittle away your compressor, there are other engine parts it's working on as well.

Thats what I'm not looking forward to, probably a factor of the blowby. I havent done a driving run with the T'd vacuum guage but did a engine hot test with the guage on the vaccum at idle and at higher rpm sustained for a bit (not overly too long) the vacuum pump kept up its end. so then came the test of the vaccum/wg pot for the turbo. It held a 25lb vacuum for over 10 minutes (pee break/beer method), I even tried to force open (gingerly) the WG while the pot was under vacuum- it didn't budge.

I dont think i'm defueling because of the tons of blacksmoke out the tailpipe when I lose boost, but I could be wrong. not 100% deisel savy but learning as I go.

But I agree about the turbo, I think the impeller is caput. and probably from the 94-95 airfilter design (not really a big fan of flat filters), I guess a 97-up filter assembly is in my future. I do a lot of wheeling/camping in the desert both in Ca and Az and have some serious grades to pull; Tejon pass(Grapevine),Cajon pass(I-15),Chiriaco Summit(I-10), LeeVining (HWY 395) just to name some. The factory setup (probably on its way out andwasn't up to snuff) wasn't cutting it pulling the trailer engine temps up high as were EGT's and maxing the speed out at 25-30mph ( little hard to cram air through the radiator at that speed :nonod: ) and to top it off most of the time the ambient air temp is around 80-90*.
95 suburban 4x4, 4:10's pulling 25' toy hauler weighing in about 9600# a bit more if I fill up the water tanks to full.
So now that I'm in need of a turbo what is recommended that would meet the needs above?

 

[Odlaw]

This is what the compressor wheel looks like on my GM-8. I had the compressor housing off for inspection and decided, what the heck - somebody on TTS might need to see one some day........looks like that day is now :sad:. Your compressor wheel looks like it has been run without an air filter for some time.

On edit; I decided to run out to my shop and snap a pic of my old GM-3 you can see some minor wear on the impeller blade tips - but not too bad for almost 200k miles.
Yes, it's late and yes it's cold (28 degrees)....but that's how we roll here at TTS.
A friend in need is a friend deed!

 

[NVW]

Thats what I'm not looking forward to, probably a factor of the blowby. I havent done a driving run with the T'd vacuum guage but did a engine hot test with the guage on the vaccum at idle and at higher rpm sustained for a bit (not overly too long) the vacuum pump kept up its end. so then came the test of the vaccum/wg pot for the turbo. It held a 25lb vacuum for over 10 minutes (pee break/beer method), I even tried to force open (gingerly) the WG while the pot was under vacuum- it didn't budge.

I dont think i'm defueling because of the tons of blacksmoke out the tailpipe when I lose boost, but I could be wrong. not 100% deisel savy but learning as I go.

But I agree about the turbo, I think the impeller is caput. and probably from the 94-95 airfilter design (not really a big fan of flat filters), I guess a 97-up filter assembly is in my future. I do a lot of wheeling/camping in the desert both in Ca and Az and have some serious grades to pull; Tejon pass(Grapevine),Cajon pass(I-15),Chiriaco Summit(I-10), LeeVining (HWY 395) just to name some. The factory setup (probably on its way out andwasn't up to snuff) wasn't cutting it pulling the trailer engine temps up high as were EGT's and maxing the speed out at 25-30mph ( little hard to cram air through the radiator at that speed :nonod: ) and to top it off most of the time the ambient air temp is around 80-90*.
95 suburban 4x4, 4:10's pulling 25' toy hauler weighing in about 9600# a bit more if I fill up the water tanks to full.
So now that I'm in need of a turbo what is recommended that would meet the needs above?

An ATT is in your future:smile5:

 

[dhjunkie]

This is what the compressor wheel looks like on my GM-8. I had the compressor housing off for inspection and decided, what the heck - somebody on TTS might need to see one some day........looks like that day is now :sad:. Your compressor wheel looks like it has been run without an air filter for some time.

On edit; I decided to run out to my shop and snap a pic of my old GM-3 you can see some minor wear on the impeller blade tips - but not too bad for almost 200k miles.
Yes, it's late and yes it's cold (28 degrees)....but that's how we roll here at TTS.
A friend in need is a friend deed!

I appreciate it a bunch....... I would definitely say that my compressor is FUBAR'D

Always ran an airfilter since I owned it Fram or wix Hd units with K&N filter spray on them.