I just thought I would share with you all how to diagnose, blue print and repair your turbochargers. Hopefully this will help you save some of that hard earned cheese.

The question I get the most that just makes me nuts is when a customer calls me and says I think I have blown out my seals in my turbo. Most of the time the customer thinks you can just pop in a seal and off you go.

Here is a pic of the inside of a t3/t4 bearing housing notice there is no majic seal.


The cut away bearing housing was from a turbo that died from a hot shut down or a car that had a stalling issue. Notice the discoloration on the right side of the unit. That is what we call the turbine side of the bearing housing. The turbine side of the turbo is the last place to get oil and the first place that looses it. So this is where the damage happens first. When a hot shut down happens most people don't know that they have just damaged their turbo until it is to late and the wheels are contacting the housings. If a hot shut down is caught in time the turbo can be repaired without much expense. You will only need a $69.00 repair kit which you can pick up from us or any diesel turbo shop that you can find.

Here is what the parts in the rebuild kit should look like.

 

Make sure you mark(scribe the compressor nut shaft and wheel) for re-alighnment. If not you can throw off your turbo balance

 

Turbos normally don't just die on their own, so determining why they failed so it does not happen again is very important.

Here are a few reasons why turbochargers fail.
1. Lack of oil or oil starvation. (this causes bluing of the turbine shaft and gauling of the frt and rear piston ring and or thrust bearing damage.)



2. Contamination of the oil would be another common cause of turbo failure. We see this mostly on rebuilt engines. Some of the machining debris gets by the filter and get stuck in the turbo causing massive wear. This type of damage leaves lines all over the journal bearing surfaces and wear lines on the turbine shaft as well.



The 2 outer turbine wheels and shaft show damage due to trash in the oil. If you can feel the scratches either on the turbine shaft or the bearing housing with your finger nail then the part needs to be replaced. Also I will give all the specs for shaft size and journal bearing and journal bearing bore size when we get into blue printing part of this discussion.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Redwidow &raquo;</TD></TR><TR><TD CLASS="quote">Make sure you mark(scribe the compressor nut shaft and wheel) for re-alighnment. If not you can throw off your turbo balance </TD></TR></TABLE>

Red is correct make a indexing line that covers the shaft, nut , and compressor wheel. This way during reassembly you will be able to index the rotating assy back the way it was balanced from the factory.

More to come after lunch.

 

Dan, was this the Candian turbo?

 

I'll be watching this thread for some good info.

 

I don't want to cover to much to fast so if you guy's have questions please ask away. Except for boostfed he is only concerned about Canadian turbochargers. We are going to covers those in 2011.

 

Alot of our turbo problems can be avoided with a lil more knowledge. Turbos are damaged on tunes most often.

Example:

1. A dyno pull WOT then ignition shut off to read plugs can lead to Damaged Thrust bearings why no vacuum to release excess pressure causing the hot side to slam against the thrust bearing.

2. Also when turning off the car immediately after a WOT pull there is no running oil going into the turbo to cool the turbo off, with a WOT pull with a now very very hot Turbo (hence oil starvation). This causes a discoloration in the turbine shaft and can scar up the turbine shaft.

3. Oil feed lines can be different with different turbos and engine applications -3an with a restrictor for a be series seems to work out for me. Honda's have a very high oil pressure which causes our turbos to ruin the turbo seals with a -3an/-4an line directly feeding them (turbo seals:basically a small piston style ring on each side of the cartridge) . I'd always use a restrictor .065 they have some pretty nice ones our these days.

Oh and my info comes from me having all these problems and learning from a turbo expert and my cuz. Which both say "boy you guys kill turbos"

 

Nice job Red. I see that alot and it normally comes along with a comment that sounds something like this. (I only have 2 thousand miles on it.) Keeping a turbo alive is all about not starving it of oil and making sure you have a good clean oil supply.

The tolerances in side of a turbo are very tight and don't leave any room for trash or oil starvation.
That is the down side of a free floating bearing system. It must have oil pressure to keep things from touching metal to metal.

On the thrust bearing all the pressure is pushing one way on the inboard side of the thrust bearing and when the engine is shut down to soon without giving the turbo ample time to spool down all that pressure burns the thrust bearing up in 2 seconds. That is what gives you the in and out play.

When the journal bearing start to wear you get alot of up and down slack and the wheels normally will contact the housing if you push all the slack out of the bearings in one direction.

As long as the wheels are not touching the housings there is a good chance your turbo can be repaired.


Modified by turbodano at 9:28 AM 9/7/2007

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Redwidow &raquo;</TD></TR><TR><TD CLASS="quote">Alot of our turbo problems can be avoided with a lil more knowledge. Turbos are damaged on tunes most often.

Example:

1. A dyno pull WOT then ignition shut off to read plugs can lead to Damaged Thrust bearings why no vacuum to release excess pressure causing the hot side to slam against the thrust bearing.

2. Also when turning off the car immediately after a WOT pull there is no running oil going into the turbo to cool the turbo off, with a WOT pull with a now very very hot Turbo (hence oil starvation). This causes a discoloration in the turbine shaft and can scar up the turbine shaft.

3. Oil feed lines can be different with different turbos and engine applications -3an with a restrictor for a be series seems to work out for me. Honda's have a very high oil pressure which causes our turbos to ruin the turbo seals with a -3an/-4an line directly feeding them (turbo seals:basically a small piston style ring on each side of the cartridge) . I'd always use a restrictor .065 they have some pretty nice ones our these days.

Oh and my info comes from me having all these problems and learning from a turbo expert and my cuz. Which both say "boy you guys kill turbos"

</TD></TR></TABLE>

are you saying you shouldnt be reading plug on a tune? if you are thats the stupidest thing ive ever heard. id rather get a little bit of wear on my turbo over blowing up a motor that cost 5X what the turbo did because i couldnt see some detonation on the plugs.

 

I've been shutting engines down immediately after a pull on the dyno for years and never seen a turbo failure because of it. I think a big difference is normally on the dyno the oil temps aren't as high as on a road coarse or something. Dunno, getting a good plug reading is more important to me than a "what if" situation. Been working for me, i'm going to keep doing it.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by CoreyR &raquo;</TD></TR><TR><TD CLASS="quote">

are you saying you shouldnt be reading plug on a tune? if you are thats the stupidest thing ive ever heard. id rather get a little bit of wear on my turbo over blowing up a motor that cost 5X what the turbo did because i couldnt see some detonation on the plugs.</TD></TR></TABLE>

If you ask a turbo expert pulling the key after a WOT pull is very bad.. It may not completely ruin the turbo. The thrust bearing will probably show signs of wear(in/out play) Happened to me right off the dyno It is different for a BB turbo.. it can get by because its a BB turbo, don't think there is a thrust bearing inside it.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tony1 &raquo;</TD></TR><TR><TD CLASS="quote">I've been shutting engines down immediately after a pull on the dyno for years and never seen a turbo failure because of it. I think a big difference is normally on the dyno the oil temps aren't as high as on a road coarse or something. Dunno, getting a good plug reading is more important to me than a "what if" situation. Been working for me, i'm going to keep doing it. </TD></TR></TABLE>

So none of the non BB turbos failed quick with pulling the key? No oil and thrust pressure. So you can't bring the car to idle for a min and read the plugs? I'm sure immediately is better but can't you get by? hmm

 

I "get by" by shutting it off when i do, i've been doing this for a minute and if i haven't seen a failure because of it, then it's not all that likely that anyone else will either. Might be bad on paper, but in the real world i have yet to see it. Not saying that it doesn't happen, but i am saying that it's not as common or easy to damage one as you might think.

 

Here is a pic of most of the tools you will need for blue printing your turbo to make sure it is still in spec for rebuilding.

The retaining ring tool is from http://www.mscdirect.com the part# we order is Rotor clip EPS-100

You will need a feeler gauge to check the clearance on the thrust bearing to the thrust collar. It should measure no more than .004.

You also will need a id gauge to measure the journal bearing inside bore diameter. On a t3 or t4 unit it should measure .621. That is what they measure when they are new. It would be ok to see .0005 wear and still be an ok rebuild but a half a thou is about all you can go.

In the blue printing faze you will need to do a dry run on the piston rings to see what the gaps are. You will also use the feeler gauge to measure the gaps. .012-.015 is the largest the gap should be. No more than this or the car will smoke a tad at idle.
Here is a pic so you can see what I am talking about. This goes for both piston rings compressor side and turbine side.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Redwidow &raquo;</TD></TR><TR><TD CLASS="quote">

If you ask a turbo expert pulling the key after a WOT pull is very bad.. It may not completely ruin the turbo. The thrust bearing will probably show signs of wear(in/out play) Happened to me right off the dyno It is different for a BB turbo.. it can get by because its a BB turbo, don't think there is a thrust bearing inside it.

So none of the non BB turbos failed quick with pulling the key? No oil and thrust pressure. So you can't bring the car to idle for a min and read the plugs? I'm sure immediately is better but can't you get by? hmm

</TD></TR></TABLE>

if you bring the car to idle it burns off anything on the plugs from the previous WOT pull, so no.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tony1 &raquo;</TD></TR><TR><TD CLASS="quote">I "get by" by shutting it off when i do, i've been doing this for a minute and if i haven't seen a failure because of it, then it's not all that likely that anyone else will either. Might be bad on paper, but in the real world i have yet to see it. Not saying that it doesn't happen, but i am saying that it's not as common or easy to damage one as you might think. </TD></TR></TABLE>

Some people are lucky and the turbo does not show signs of the damage right away.

Here is a story from last weeks Indy.
Rado and the team was 2 stepping the car in the pits when all of a sudden the air hose blows off the pole that goes over the race car and bounces off the valve cover and slings over by the turbo. Well Rado having a reaction like a cat shut the engine off right away before the hose got sucked into the turbo or got wrapped around the crank shaft. Before he shut the engine off the turbo was making 20 psi of boost. It took maybe 30 seconds for a crew member to move the hose and another 10 for Chris to start the car again so the turbo was not running dry any longer than it had to. At the end of the race weekend the turbo did show signs of wear from that happening.

Sometimes it just happens and there is nothing you can do. As far as reading the plugs on the dyno I was not aware that Hondas came with carbs on them, that is some old school stuff right there. There is easier ways to tell how the tune is other than killing a turbo to read the plugs.

If you are looking for signs of detonation on the plugs, those signs will still be there after you wait 1 minute while the turbo spools down.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by turbodano &raquo;</TD></TR><TR><TD CLASS="quote">

. There is easier ways to tell how the tune is other than killing a turbo to read the plugs.

If you are looking for signs of detonation on the plugs, those signs will still be there after you wait 1 minute while the turbo spools down.

</TD></TR></TABLE>

come on dano ! what better way to see whats going on, other than diagnose the plug.

 

subscribing to aome great info

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by turbodano &raquo;</TD></TR><TR><TD CLASS="quote">


Rado and the team was 2 stepping the car in the pits... Before he shut the engine off the turbo was making 20 psi of boost....At the end of the race weekend the turbo did show signs of wear from that happening.


</TD></TR></TABLE>

I don't think you can really relate that kind of condition to the way most people tune a Honda.

...and yes, you can foul out a plug by letting it idle for 30 seconds after a hard pull if it's rich. Hence the part of "tuning" the car to get the correct tune.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nsxmatt &raquo;</TD></TR><TR><TD CLASS="quote">

I don't think you can really relate that kind of condition to the way most people tune a Honda.

...and yes, you can foul out a plug by letting it idle for 30 seconds after a hard pull if it's rich. Hence the part of "tuning" the car to get the correct tune.</TD></TR></TABLE>

It is the same thing as making a wot pull on the dyno and killing the key before the tires stop rolling. If it is that rich that it fouls the plugs at idle you wouldn't be able to clearly see the plug cause your eyes would be watering to bad lol.
Two words for you wide band.

We dont tune by the plugs and we are making 1700 bhp @ 70 psi and our motors live the entire weekend. Gary G went through six engines last week at Indy. I think he must tune by the plugs.

People can take care of their turbos anyway they would like. The more yall break the more money us turbo shops make. I am here just to edjucate peeps on why they break so they don't think it's always the turbochargers fault. After all they are not bullet proof. Nothing that turns 100k+ rpm is going to be bullet proof.


Matt I do understand what you are saying and as long as your turbochargers are not failing I would not change a thing.
Good stuff, so keep it coming.

 

You keep building turbos, and i'll keep tuning engines...

 

i have a turbonetics t3/t4 60 trim. works fine. i bought it new off this other guy. i was wondering how do i know if has a restrictor in it? also what is the psi of oil that shold be going to it?

 

Once again turbodano looks like a big dumb dumb. Bringing the car down from 10000rpm to 1200rpm, you are probably going to go through a couple of ignition cycles. More than enough to change the way the plugs looked.

$1000 or less engine, det cans/electronic knock detection is fine. When your engine starts costing a lot more than your turbo, pull the plugs. See what is going on in the engine. It's not like we are talking about shutting down the car 50x a day, every day. You do it less than a dozen times on the dyno and maybe 1-2 times before an event if you feel your tune could be off.

 

I guess tuners and turbo guys will agree to disagree on that topic. Not like it is a wide spread epidemic.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DrivinVtec &raquo;</TD></TR><TR><TD CLASS="quote">i have a turbonetics t3/t4 60 trim. works fine. i bought it new off this other guy. i was wondering how do i know if has a restrictor in it? also what is the psi of oil that shold be going to it?</TD></TR></TABLE>

If it is a journal bearing unit the restrictor is normally screwed into the oil feed hole of the bearing housing. What does the top of the turbo look like? What kind of fitting does your oil feed line connect to? Put up some pics.

Idle oil pressure should be no less than 12 psi and no higher than 55 psi. The magic number for performance is 40 psi at the turbo. The higher the oil pressure at the turbo the more of a chance you have of out flowing your oil return system.

One thing most people don't know is that oil pressure over 40 psi makes the turbo laggy and slow to spool.