turbo squeal/whistle

[aptacek]

My turbo whistles/ whines when it spools up. I know some noise is normal,

how ever this seems to be more noticeable while driving, and it is consistant, the whine down can be also heard as I let off of the throttle . The only motor work that has been done was the head gasket was replaced, but that has been done in Dec. , and there has been at least +2000 miles on it. I tried it to re-create the condition while parked and grabbing the throttle linkage can't hear nothing, figure the turbo requires load to "spool up" The truck has +200,000 miles. Only mods are the 40hp BDL injectors and a KN air filter, and a stock 5 speed mans. tranmission, 4wd

any help would be appreciated



Thanks

Andy

 

[CMckee]

first off, if you fill out your signature with your truck info it would really help others help you. first a question, have you owned the truck from new? if not someone may have taken out the silencer ring from the turbo, this makes the turbo whistle considerably louder in the cab, which a lot of us have done. and you are rightthe turbo hardly makes any noise unless it's under load.

 

[swankmetal]

hello and welcome. i have yet to hear a "bad" turbo, but i'm sure others will chime in. is it all of a sudden louder? the first thing i would check would be all the connections between the air filter and turbo. if you haven't already done that, probably be a good place to start. and if i were you, i'd ditch the k&n and get a bhaf (big honkin air filter). you can get them from napa for 50 bucks.



dave

 

[bgilbert]

Normal, relax.

 

[Dieselman359]

Watch out

Ya know aptacek, as soon as I read your first sentence, I thought to myself, I hope that Bill doesn't see this. I see that he went easy on ya though.



I wouldn't worry about it. I drove around all say yesterday with the windows down on my VW so I could hear the turbo. :-laf

 

[paccool]

Chris,

No silencer rings on a stock 1st gen turbo.



Andy, I would pull the inlet hose off and check for excessive shaft play in the turbo. There have been a couple of guys report noise and it turned out to be the vanes on the impeller rubbing on the housing. Will just take a minute to check.

 

[JLEONARD]

There have been a couple of guys report noise and it turned out to be the vanes on the impeller rubbing on the housing

I be one of those guys a few years ago.

I was fortunate that I suffered no engine damage (that I know of) from all that aluminum dust.

Check the impeller for play... NOW. Pull forward on it (while the engine is NOT running) with your fingers and make sure it can't come forward enough to hit the housing.

You'll be glad you did.



Jay

 

[TKingsbury]

If it doesn't sound "normal" to you, then check the turbo. We have had a few turbos grenade the compressor wheel and get a bunch of oil and parts in the intake tract on trucks at work. It isn't pretty. The good part is the intercooler catches the big chunks. When in doubt, check it out!

Travis. .

 

[aptacek]

Thanks for all of the input; I have owned the truck for 5+ years, and something has definitely changed in the last 3 weeks/500 miles.

I attempted to update the signature card, it does not let me edit, change etc.

The truck is a 1990 3/4 ton 4wd regular cab pickup, with the stock getrag

transmission. The 40 hp BDL injectors or the only major motor mod.

I will look into the BHAF. It does not have an intercooler, so it will not be driven until I inspect the compressor side of the turbo. I have other vehicles to drive. If there is rubbing, end play etc. , Where do I start to find replacement parts? I live in the Portland OR metro area. I have been considering going to the 16 cm turbo housing, should I consider a aftermarket unit that is bolt on ready and will give sufficient boost? I do realize guages will have to be a requirement if I do the performance upgrade. The truck will be pulling a mini excavator or a 1845C Case skidsteer 400 miles to my recreational property once a month.



Please advise



Andy

 

[swankmetal]

i would highly recommend calling high tech turbo in ogden, ut. talk to paul and get "schooled on turbos". htturbo.com will give you hours of reading.

 

[caleb c.]

Aptacek,I have a good H1C for cheap if you end up needing one. PM me for details.

 

[JApplegate]

here i go again... be carefull! turbos are very picky!... u mess it up a little u'll be lucky if u get out it alive. when those things blow they take the cummins with it!

 

[JLEONARD]

Aptacek,

A stock H1C from an intercooled truck will be a nice upgrade for you, but you will need to "scrounge up " some additional parts in order to make it work.

The newer turbos have a 4 inch intake into the compressor, so you will need a different intakee hose arrangement.

The outlet to the crossover is also different and you will need to adapt that as well.

I am in the process of making this change right now... my temporary set up is similar to DPuckett's (he has a pic in his reader's rigs).

My new crossover tube will go on this weekend... I'll post a pic when I'm done.

(Can't do it now... I'm in Brazil)

Jay

 

[dpuckett]

You mentioned a screeching noise. Is this under load, or just in sync with the turbo? How long after the head gasket job did you notice it? I had a similar noise in my (non intercooled) 91, changed the turbo, no change. I read on the DIS of Pittsburg website that the noise could be a HG in the N14s. After eliminating ALL other possibilities, I replaced the HG, and the noise has stayed at bay the last 45K.



Retorque the head bolts if the turbo checks out ok.



I dont think the 40HP BD injectors will give you much more than stock- the nonIC engines have bigger holes, flow more fuel than the later IC trucks.



Daniel

 

[tugboatphil]

(Can't do it now... I'm in Brazil)

BRAZIL?!



Jay,



Does this have anything to do with that rumor we were going to start last year. The one where a rich guy decides to retool a plant in South America, to build new 1st Gen trucks. I thought that was just made up. Now if you're holdin' out on us... ... . :-laf

 

[JLEONARD]

where a rich guy decides

Then it's obviously not me!! :-laf :-laf

But here's a link to where I am right now.

Will be back in Ct tomorrow.



http://travel.yahoo.com/p-travelgui..._friburgo-i;_ylt=AgGmlulsQj_3scsQbZFlIqryWGoL

 

[aptacek]

I sent the turbo to hi tech turbos in UT, they went thru it and also put the

16 cm housing on it. Have re-installed turbo and I still have the load whine

more then normal. It will only do it under load, which leads me to believe

and air leak. I have looked at intake air ducting and related items, serviced the KN (Which has been in for 1. 5 yrs). My next thought is to to go to the

Dyno day in Vancouver WA 4-16-05. The facility is only 15 miles away.

The idea I have is hopefully I can find one of the NW bombers there that would either run the truck on the dyno of be willing to pin point the

whine while, under load on the dyno. If any one has another idea to

try and simulate the problem while not moving or another way to check for leaks let me know



Andy



1990 3/4 ton reg cab, 4x4 40 hp BDL injectors, 16 cm turbo housing

Stock Getrag 5 sp transmission,

 

[JLEONARD]

I built a simple test rig out of some 4 inch PVC pipe fittings and a few air fittings and a gage that the air box hose clamps to... I can pressurize it and find leaks using soapy water.

As a matter of fact I used it last night and found a couple of leaks that need attending to.

Jay