Turbo Lubrication Problem

[TurboRaider]

A hand held temp gun aimed at the oil pan is a quick way to verify your oil temps as well as into and out of the oil cooler. The oil thermostat is a good thing to keep. Cold oil builds up moisture causing acids and extra wear. Low oil temperatures lowers HP and creates extra friction.

 

I have found that flex lines dont do well when connected close to the turbo. I really think a hard line is the best way to connect the last 8" to the turbo for both the water and the oil.

 

Kevin C

[UNDRPRSR]

So your saying to remove the oil cooler bypass valve and insert a washer in the opening that will put more pressure on the spring (opening the valve) when the valve is reinstalled?

 

Yes, if your spring is intact but just worn, you can shim it to apply stock like pressure.

[Shelby]

what ever you do ,do not do things for no reason,,test first and only fix what has a problem,, randomly doing this and that may cause other problems and hide the real cause

personaly i'd do away with the fex hose and try a metal oil fed line ,sence thats the most likely canidate, after all it's only like $10 bucks new

[UNDRPRSR]

what ever you do ,do not do things for no reason,,test first and only fix what has a problem,, randomly doing this and that may cause other problems and hide the real cause

personaly i'd do away with the fex hose and try a metal oil fed line ,sence thats the most likely canidate, after all it's only like $10 bucks new

 

Don't take this the wrong way Shelby, but I wouldn't recommend things for no reason. It's happened before on two separate cars, this was the problem both times and it doesn't cost anything to try it. Shiming that spring is what I would call a "test" and if it works, then order the new part. If it doesn't, no cost incurred and you can try something else.

[Shelby]

i wasn't replying to you but to the guy working on his car .

 

i've seen it over and over again,,lots of guys do not like to take the time to do tests or check system operation ,it's quicker they think just to do this or that and see what happens

in truth that is not the quickest way

ihave seen oem heavy duty oil cooler lines go bad on the inside of the flex hose,, so why can't these after market hoses do the same thing

 

and i have replace'd more BMW volvo and M-benz flex brake lines then i care to remember

how does that relate,,it's all the same hose only diff is the inside id

 

UNDRPRSR i was only trying to warn him about asumeing and not doing the test's checks,, i have great respect for your knowlege and experiance , sorry if you took what i said in a diff way

Edited May 2, 2008 by Shelby

[UNDRPRSR]

UNDRPRSR i was only trying to warn him about asumeing and not doing the test's checks,, i have great respect for your knowlege and experiance , sorry if you took what i said in a diff way

 

Back at ya, sorry about the misunderstanding.

 

Jayton, let us know what you find. This is becoming a common problem and all the info we can get will be useful.

[TurboRaider]

50,000 foot view...

 

If the oil is getting so hot that its killing the turbo, I doubt the other bearings would be in very good shape and the oil annlysis would have shown that.

 

Hot oil usually results in coking, sludge and short oil life, like 2000 miles: not 50. Having the oil at the right temp does help but this is to happening a bit too fast. Checking the oil T Stat is a good idea, however as other have pointed out (including myself) braided lines and hot turbo's are not a good mix. I learned this on the cooling lines, I hade a failure after two years when using high quaility AN type lines. IMHO its either a batch of bad turbos or oil starvation.

 

Kevin C

Edited May 3, 2008 by TurboRaider

[Shelby]

with the short time it's takeing to wear the turbo shafts it has to be very little oil geting to the turbo brgs ,,and if thats the case a drain back hose check for oil volume will show that up as the cause

 

oh and for the guys mentioning the crank case blow by pressure,,the engine oil system is under 30 to 80 lbs pressure and no way the crank case can ever get that much pressure so the oil would push into the crank case eventualy , even tho it may back up in the turbo houseing a bit ,,but that would not cause oil starve'd shaft brgs

[jinx]

oil feed to turbo may be 30-80psi... but, its thru a tiny little orifice

 

....vs a big cavity in the CHRA that can easily be filled with crankcasepressure - hindering oil flow.

This actually causes our nissans to smoke, if not addressed.

Just a thought

 

Unlikely culprit, since crankvent in effect here.

I too am trying to understand how a mal-functioning oil cooler bypass factors into starving the turbo.

Hope that pinpoints the source. Not like turbo rebuilds are cheap

[Jayton]

oil feed to turbo may be 30-80psi... but, its thru a tiny little orifice

 

....vs a big cavity in the CHRA that can easily be filled with crankcasepressure - hindering oil flow.

This actually causes our nissans to smoke, if not addressed.

Just a thought

 

Unlikely culprit, since crankvent in effect here.

I too am trying to understand how a mal-functioning oil cooler bypass factors into starving the turbo.

Hope that pinpoints the source. Not like turbo rebuilds are cheap

 

Hey guys, Thanks again for all of the input. I have not had much time to perform any of the tests or to check anything out, but am still putting a lot of thought into this and all of your input helps. What sucks is that i could definitely go through a few more rebuilds until knowing for sure if i have solved the problem. If I fix the problem now I won't be able to tell with the current turbo because it is already worn.

[PDX87Starion]

Are you absolutely sure your crank vent valves are in the right way?

 

If either one is backwards your CC will be pressurised.

 

Also if the big KV fills with oil from oil vapor, under boost it can block the CC gasses from excaping causing high CC pressure.

This is when your dip stick starts to pop out, as seen with others.

 

Many of us here think that (under boost) the KV sytem is a downgrade from the stock separator system.

Others say it works just fine.

 

Do a search if you want, there has been long threads on the KV topic.

[Shelby]

i can't see any turbo geting damage at idle as long as it's geting any oil at all

there is anpother oil port that could be use'd to fed the turbo and thats the plug in the block ahead of the oil filter houseing it would not begoing thru the oil cooler but at the same time it should not get hot enought to loose all lube ability, after all several cars do not have an oil cooler supplying oil to the turbo

so what we have left is some thing is blocking the oem oil supply or the hose feeding the turbo is restricting the flow volume, the DSM's use an oil port on the rear of the cyl head so we know a diff source will work

 

if the temp valve on the filter adaptor is not working the oil cooler will not get hot simple as that

the auto trany cooler has a similar temp valve on it,,that was one of the first things i did away with

[Jayton]

Are you absolutely sure your crank vent valves are in the right way?

 

If either one is backwards your CC will be pressurised.

 

Also if the big KV fills with oil from oil vapor, under boost it can block the CC gasses from excaping causing high CC pressure.

This is when your dip stick starts to pop out, as seen with others.

 

Many of us here think that (under boost) the KV sytem is a downgrade from the stock separator system.

Others say it works just fine.

 

Do a search if you want, there has been long threads on the KV topic.

 

I am absolutely sure the Krank Vents are in the right way, but i'll check again just for arguments sake. I have never had my dipstick pop out. My dipstick actually has a lot of suction/vacuum while the engine is running. If I pull the dipstick when running it sounds like a vacuum being released. I also noticed that the ball in the PCV valve will rattle on and off while the car is idling and if i pull the dipstick and release the vacuum the rattling stops.

I believe I was supposed to hollow out the PCV when using the Krank Vent, but I never did. Could this be causing trouble?

 

I'm all for removing the Krank Vent system if the general consensus is that it's not beneficial to the performance. Prior to the Krank Vent I used a breather on the valve cover. I no longer have the stock seperator system and do not see myself putting it back on. Currently I have the nipple on the oil pan that went to the stock seperator is capped off.

 

How could I tell if the Krank Vent has oil in it? Would it drip out if removed?

Edited May 9, 2008 by Jayton

[Jayton]

I finally got to drive the car again yesterday and the oil cooler definitely gets hot so i think I can rule out the thermostat switch on the oil filter adapter. Next I'll look into the oil feed line and any problems that may be in that area.

 

I also never mentioned that I have a 'spacer' between the CHRA and the oil drainback tube. I did this because the drainback tube does not clear the compressor housing otherwise. The spacer I'm using is actually just a flange that i cut off an old drainback tube. I am also using 2 gaskets to make this work.

Edited May 15, 2008 by Jayton

[Jayton]

What happens if too much oil pressure blows out the rear seal on the turbo?

Would the turbo be starved of oil at higher RPM's?

 

My car definitely uses some oil with the turbo in the condition it is now so I'm wondering if the rear seal is shot. Then I'm wondering if too much oil pressure caused the seal to blow.

 

Would I be using oil if my only problem was insufficient lubrication of the turbo?

[Indiana]

you the one on the 3rd turbo they keep burning up? is that your engine bay all shiney there in those pictures?

[Jayton]

you the one on the 3rd turbo they keep burning up? is that your engine bay all shiney there in those pictures?

Yes that would be me.

[bamf]

any news? fix it or blow it up?

[mikec]

Any updates on this? If it's still a mystery, I have a few off-the-wall ideas:

 

1: any chance you've got an incorrect dipstick in the car - how much oil do you have to put in when doing an oil change to get a "full" reading? You might be running a quart (or more) low on oil all the time... so slosh during high acceleration or cornering is leading to oil starvation. The dash oil pressure guage is VERY VERY SLOW to react - you will NOT see this on a stock gauge. A true mechanical gauge will blip though.

 

2: a weak, damaged, or worn-out o-ring on the oil pick-up tube (where it plugs into the oil pump) will leak, allowing air into the oil.

 

3: crud in the turbo's oil passages. If the damage/blue-ing is always in the same spots, it may be that one dinky passage inside the turbo is blocked... oil can flow through others (so you get roughly normal oil flow from the turbo drain hose) but certain parts of the turbo don't get enough oil. Of course this requires another turbo dis-assembly... ask the rebuilders how they clean & test the cartridge.

 

4: ask the rebuilders what excessive oil pressure would do to your turbo... and if they've ever seen those symptoms during your rebuilds. If your engine oil pressure is excessive, the restrictor on the turbo oil feed line might not do enough and you get excess pressure inside the turbo. That can blow seals (moves them "out of the way") and then, when oil pressure returns to normal/idle levels, the oil now leaks around the bad seals and less gets to the bearings leading to turbo bearing failure.

 

 

To add to what Shelby and others have said about the oil feed hose... we've also seen folks with real mystery fuel supply issues. The rubber section of the fuel hose (from the fuel filter to the throttle body) tears internally (like a hangnail on your finger). This "flap" sometimes folds over and blocks a lot of the hose. At idle, there is enough fuel flow to read normal pressures and the engine idles fine... but under acceleration the half-blocked hose starts choking off the fuel flow. Rubber brake hoses do something similar. Sometimes the flap acts like a "check valve" - brake pressure passes to the calipers and the brakes work okay... but when you lift the pedal the check valve activates and traps the pressure - so the caliper doesn't release and you have dragging brakes! Hose failures can be VERY funky.

 

mike c.

[Jayton]

Any updates on this? If it's still a mystery, I have a few off-the-wall ideas:

 

1: any chance you've got an incorrect dipstick in the car - how much oil do you have to put in when doing an oil change to get a "full" reading? You might be running a quart (or more) low on oil all the time... so slosh during high acceleration or cornering is leading to oil starvation. The dash oil pressure guage is VERY VERY SLOW to react - you will NOT see this on a stock gauge. A true mechanical gauge will blip though.

 

2: a weak, damaged, or worn-out o-ring on the oil pick-up tube (where it plugs into the oil pump) will leak, allowing air into the oil.

 

3: crud in the turbo's oil passages. If the damage/blue-ing is always in the same spots, it may be that one dinky passage inside the turbo is blocked... oil can flow through others (so you get roughly normal oil flow from the turbo drain hose) but certain parts of the turbo don't get enough oil. Of course this requires another turbo dis-assembly... ask the rebuilders how they clean & test the cartridge.

 

4: ask the rebuilders what excessive oil pressure would do to your turbo... and if they've ever seen those symptoms during your rebuilds. If your engine oil pressure is excessive, the restrictor on the turbo oil feed line might not do enough and you get excess pressure inside the turbo. That can blow seals (moves them "out of the way") and then, when oil pressure returns to normal/idle levels, the oil now leaks around the bad seals and less gets to the bearings leading to turbo bearing failure.

 

 

To add to what Shelby and others have said about the oil feed hose... we've also seen folks with real mystery fuel supply issues. The rubber section of the fuel hose (from the fuel filter to the throttle body) tears internally (like a hangnail on your finger). This "flap" sometimes folds over and blocks a lot of the hose. At idle, there is enough fuel flow to read normal pressures and the engine idles fine... but under acceleration the half-blocked hose starts choking off the fuel flow. Rubber brake hoses do something similar. Sometimes the flap acts like a "check valve" - brake pressure passes to the calipers and the brakes work okay... but when you lift the pedal the check valve activates and traps the pressure - so the caliper doesn't release and you have dragging brakes! Hose failures can be VERY funky.

 

mike c.

 

Sorry Guys, I have not been recieving email notifications of replies to my topics or posts otherwise i would have responded sooner. See my replies to the suggestions below...

 

In response to #1

I have had the same dipstick since I bought the car in '93. I I have to put it just under 5 quarts if I remember correctly.

 

In response to #2

Yeah, I checked into this about a year or two ago upon suggestion from someone (may have been you). I dropped the oil pan and pulled the oil pickup tube and checked out the o-ring and even replaced with new.

 

In response to #3

I have had the rebuilder thoroughly check all of the passages and inspect for ANY cause of concern. They have found nothing of concern.

 

In response to #4

I don't have a restrictor on the oil feed line as there is none in stock form and not typically needed on cars that are factory turbo or that have journal bearing turbos (from what i understand).

 

Lastly,

I have purchased a new oil feed line to rule out the possability of any internal tears or blockage on the hose like you are tlaking about. I have also decided to use the port on the side of the block as an alternative source of oil to feed the turbo and have plugged the oil port on the oil filter adapter.

I am putting the car back together now. I put an M6 head and new header on and have to button it all up. I'll be in good shape for when the weather turns. I have also rebuilt my two 20G turbos (primary and backup). Let's hope I won't have to use the backup one.

 

 

[Guest c89zx7r]

what are your other mods to support the 20g? ever think about running lean, glowing turbo/header and overheating the turbo to the point it starts to bake the oil?

[pitboss]

Jayton, let us know what you find out. Also, I have an almost totally stock auto, and I changed out the stock turbo oil feed hard line, in favor of a new JollyRoger SS line a few months ago and so far no issues. I used the same TEP SS line you have for years also on my other car with no issues. Edited December 29, 2008 by pitboss

[Jayton]

what are your other mods to support the 20g? ever think about running lean, glowing turbo/header and overheating the turbo to the point it starts to bake the oil?

 

Yes I have thought about this. I had installed a wideband last season and it was reading fine, but other factors indicate that I am running on the lean side.

So you are saying that a lean condition which increases heat in the turbo could actually bake the oil while the car is running and therefore starve the bearings? I had asked my turbo rebuilder about this and he didn't think it was a probable cause, but I'm willing to explore all options.

 

Besides, don't all turbo's/headers glow under hard/high boost conditions even when not running lean?

 

As far as supporting mods: fuel pump and lines, ignition module, header, exhaust, ported and polished head, blah, blah, blah. Nothing in the way of upgraded or additional injectors yet though.

Edited December 31, 2008 by Jayton

[garychoffmann]

Make sure that your KV coming out of your valve cover is allowing pressure out. The easiest way to do this would probably be to stick a hose on it and run it into your cabin and just hold your thumb over it. If pressure is escaping then it's working properly. I would do the same with the one running to the intake. Under boost make sure that there is no pressure on there. You should be well safe gaurded with your pcv still hooked up in factory trim. It probably wouldn't hurt to take off your pcv and krank vents and clean them really well. Check to see if those lines have pressure. one off the valve cover should, one off the intake manifold shouldn't(under hard driving). I've seen these fail before so I'd definately check those out.

 

Also, if you are running high cfm/boost and your engine isn't in the best of shape, the CC pressure could over compensate what the KV can vent. If the CC is pressurized it will not allow the oil to flow out of the turbo. I believe this may be a venting issue/ oil draining issue. KV's are much like a pcv valve IMO. How much they can flow verse what your engine is producing is the question I have.

 

How long have you had this engiine? Have you always had this problem since this combo was introduced (turbo/engine). I have other questions about your turbo but we'll start here. I'll look into weight of the different wheels. If one wheel is heavier I wonder if it can put stress on the bearings. Sounds goofy but think GYRO. You know one of those things that you spin and hold iny our hand but no matter how hard you try you can't hold it straight. It makes your hand move with it. Wonder if 2 objects, weighted differently would put force on one bearing or the other.

[Jayton]

Upon the input of another member via PM and the suggestions/input you guys have provided here I am beggining to strongly believe that this is a crank case pressure problem. What I did not realize about the stock seperator and PCV setup is that it actually uses the Turbo to create a vacuum under boost to relieve CC pressure. I honestly don't believe the rear KV is capable of relieving the CC of all the pressure a 20G at 15+ psi produces.

 

Even before I had the Krank Vent setup (and before the 20G) I have always had a breather on the rear port of the valve cover (and i have had the car since '92) After completing the restoration with all the mods and upgrades is when I installed the KV system. I had removed the KV system in the past when I had suspected it might be problematic and noticed no difference, but I was using a breather on the rear of the valve cover. I have never fully returned to the stock seperator setup and I think it's time I do this! I believe I need the vacuum it creates to extract the excessive pressure the larger Turbos create.