Help with Turbo oil leak

mcbusaturbo

Registered
So I am no dumby but I am deffinantly no expert and that is why I came here. I have been here a lot and read probably majority of posts... I finally joined and need to ask the help of some of you brighter individuals that I read so many replys of. I got a turbo kit (half a kit) from someone who bought it and then needed the money before it got installed and I bought it off of them, so it is new I looked over the components and it was easy to tell it was new.

The problem is a little oil drip coming from the compressor housing. it is a velocity kit, most of it. and it has a -4 inlet I believe it is about a 1/4 inch coming in I haven't measured it but around that. coming out is a -8 it is 3/8 line coming out for the return. the turbo sits higher then the oil pan and it drops out of the turbo and makes a sweap to the side of the oil pan (aftermarket 2 inch flat bottom pan forget the manufacturer name though) were there is a large 90 degree bulkhead fitting going into the side of the oil pan -8 (had to drill a 3/4 inch hole in the side of that brand new $500 oil pan). it seems adaquate but I am no expert. I really don't want to have to have a pump for it and I don't think it needs it either. the turbo is a Gerret T28.

I am just needing some help as to how to get rid of it, I heard that people run the oil lower (no oil cooler) in the sight glass like by the min, any truth to that? it makes sence because you don't need that big of a surplus of oil without the oil cooler but I am not sure. oh and the fitting is in the side, only about a half inch from the top of the pan. no uphill run on the oil drain line either, and the turbo sits level, and is only maybe 5 degrees out from being perpendicular from the ground.

If you can help with some ideas great or how you guys have it ran, wonderfull. I am looking for any suggestions on what could be the prob. If I need to include more info I will


OH yeah.... Happy 4th everyone....

no oil system mods, except removed oil cooler and
removed the restrictor because of the block offs

compression is good so I wouldn't think blow by would be
a problem cause cylinders seem good.

K&N air filter, flows 380cfm per K&N guys which should be ok
for me (7psi, stock displacement, K&N said at 100% efficiencey
it would only need about 400cfm)


so any help at all would be great and if you need more info I can provide.
 
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Id go down to a -3 AN oil feed line
and possibly add a .06 restrictor in the feed line also
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I thought about a restrictor and I am greatfull for any and all input... thanks for replying. My only question about restricting the inlet is how do you know you are getting ENOUGH oil to the turbo, because it is basic bearing style not a ball bearing and the oil is the only cooling source and also the only real lubrication/bearing. I know I ask a lot of stuff but I like to know exactly what is going on.
 
Some of the early velocity stuff mounted the turbo a little lower than later kits
i have one of there early headers on my streetbike, cut 3/4 " out of the header just above the turbo flange and never had any problems,
but even the low header can work ok,
as you mentioned don't over fill, having the oil nearer the low mark will help,don't use a rear stand , or if you do.. know it will burn or leak some oil as your tipping the oil into the turbo by lifting the rear.
go over the bolts on the turbo centre and be sure there tight,
double check the breather is not restricted in any way as crankcase back pressure will restrict the oil flow down the drain
 
Humm.........do you have any extra oil being shot up into your charge tube? Meaning coming out the compressor side, not the exhaust side?
 
yes there was evidence of oil in the intake pipe, but there is no oil burning out the exhaust at all, not even on start up.

I do use a rear stand a lot, I had thought about that just wasn't sure if that would weep by the seals when it wasn't running, also my side stand is to short so the bike leans a bit more then I like (I had it lowered more before and then scraped some parts so raised it up a bit more cause I like the corners a little too) I am buying a new adjustable one, because I thought about that to the oil is running all to that side which could want to push it through the return line (my return is on the left side of the pan) and into the turbo. I sort of dismissed those ideas though a little because I would think it would burn a little oil to then because isn't it the same seals/bearings on both sides?

the turbo is mounted just above the oil pan, so that the return line does not run up hill at all. I read on the Garrett site that they say the return line should attach ABOVE the oil level, but there is no way to do that as far as I see. I have seen where people mount the return on stock oil pans into that low hanging spot on the oil pan where the stock pick up goes down in, I am wondering if any of them guys with the return there has a problem.

and the breather, what size crank case vent do you guys have??? I have the MPS short breather cover and I believe it has a 3/8 opening that my little filter is attached to. I thought of putting a gauge on there and seeing what kind of preasure/vacuum might be present in there, has anyone done that? What size crank case vent do you guys have? and my crank case vent is new, and still clean.

once again thanks for all and any help

an earlier post was about a restrictor and there is one I am going to remove the feed line and check the size of it to make sure, Garret did say around .06 for journal bearings and .32 for ball bearing type. mine is just journal type bearings.
 
Do you run any kind of scavenge oil pump to help pull the oil back into the pan? I had this problem as well, & if you don't deal with it, you will ruin the turbo seals.

Cody
 
I think your rear stand will be a lot of the problem, see if you can get a front stand, it will hold the front high and keep the bike straight , the oil will be collecting in the compressor , side stand may also be tipping the oil above the turbo .
your oil return is about as good as you can get , my racebike runs similar with no probs
mine use a std breather with the hose pointed at the chain, figure if its going to breath a little oil it may as well be doing some good
 
True, I do have to put my bike on only a front stand because if i dont the turbo fills with oil big time, then when it sits for a couple days the next time i ride it she spits oil all over! If i put it on the front stand, i have no problems! :beerchug:
 
Do you run any kind of scavenge oil pump to help pull the oil back into the pan? I had this problem as well, & if you don't deal with it, you will ruin the turbo seals.

Cody
We often used scavenge pumps and also (make sure line is vented if this is done) Probably not going to have much effect on a leak that only happens after oil runs back after shut down btw..

Restricting the feed line will not help for oil that leaks back down after shut down either.

We only restricted feed lines that had issues when running (IE hi pressure oil systems that would force oil out past the seals in the turbo when running after making sure that crank case pressure was not the real culprit)

We fixed a few of these by using a catch can on the turbo drain and then running the scavenge pump on this tank.. (make sure tank is vented to outside world via crank case vent)
 
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Having a very similar issue. Just once though after a good ride with some folks I parked the bike in a lot and there was some oil right below the intake filter on the turbo K&N Filter. Motor has less than 500 miles on it. Wondering if I am having the same problem? Rode it home next morning no oil. Rode it to work today no oil. I don't understand...
 
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