Burning oil 4AGTE

[turbo_gze]

Just recently did a turbo conversion on an ae101 4agze with a RB25DET turbo.

Got a problem after 30 seconds of cold start up oil starts to burn and comes thru out of the exhaust system. After 5 mins of warm up and then a few mins of driving the burning of oil is gone.

The Turbo oil line is T pieced of the oil filter relocation kit close to the block.

The oil line that goes into the turbo is 5mm in diameter and all fittings to go with are the same size.

The return line is 19mm in diameter and mounted to the highest point to the rightest of the sump so oil in the pan is affecting any flow.

Did bit of a search and found that 1.5mm to 1mm is minium oil line required to feed the turbo. I was thinking of taking the fitting to Pertek to get the nozzle that screws into the turbo redone to 1mm. I asked a guy who rebuilds turbos he quoted me that, If i restrict the line it will affect the turbos lifetime and engines life time. I dont see how the engine will be affected because from factory there was never a T peice line going to a turbo?

The mechanic who did this conversion for me stuffed it up by putting a 10mm line braided to return back to the sump it was pissing out smoke so bad it wasnt funny. I quickly changed it to 19mm hose and it helped alot.

There is not shaft play in the turbo at all.

[fixeruperer]

if the inside diameter is 5mm to the turbo thats too big try 2mm, and when you restrict it do it on the turbo end of the hose not the block.
the rb25 turbo is ball bearing aswell and doesnt need as much oil.

[allencr]

5 mins of warm up and then a few mins of driving the burning of oil is gone.

Condensation. At least you didn't say oil/gasoline is spitting out the ex. pipe!

[turbo_gze]

Condensation. At least you didn't say oil/gasoline is spitting out the ex. pipe!

Its a bluely color smoke.

[YLD-16L]

You have a decent sized return line but does it remain close to vertical all the way into the sump or does it get close to horizontal when it enters?

Just seems odd that going to the larger OD drain helped but didn't completely solve the problem.

The restrictor will help too if it's an oil supply/drain problem but as mentioned fit the restrictor at the turbo end of the feed line and ensure the drain is well setup.

Oil smoke stinks like shit so there should be no confusing it with condensation burning off after a cold start.

[allencr]

Its a bluely color smoke.

OK, sorry to have to question condensation, have never worked on one and have only been in one going out for a quick parts run.
So if it clears up when hot when the oil flow must be better, it's been there from accumulating when it's been shut down and that's the 5 minutes you see burning up.
Oil feed on the bottom or top?
Is this the sign/s of a turbo on its last legs, guessing bearing/s that are loose & breaking/stretching seals, or just a bad seal that'll work when it's under pressure? Side & end-play?

[turbo_gze]

The oil feed is on the top.

The return line is horizontal but on 35 degree slope. Highest point being the turbo then lowest the sump.

There is not shaft play in the turbo too.

[YLD-16L]

The return line is horizontal but on 35 degree slope. Highest point being the turbo then lowest the sump.

So the fitting into the sump is an angled connector or angled fitting I gather. Sounds like the drain shouldn't be an issue.

[Cuzzo]

How long was the turbo run with the smaller oil drain?

[feral4mr2]

you'll find a turbo (unless really shagged) will emit smoke at idle and not when running as there is no internal pressure in the turbo at idle, making it easier for oil to seep past the seals/bushes.
i filled a fitting with solder and drilled a 1.5mm hole in it to restrict the oil feed to my t25 (placed on turbo end), solvered my smoke issues. though i have not used a ball bearing turbo, i beleive they can use as small as a 0.8mm oil restrictor. (someone will comfirm this i am sure....).

[limbo]

ball bearing turbos require a restrictor. Otherwise the oil floods the turbo and it seeps thru and damages the seals. The restrictor i got was part of the fitting to the turbo. Most fitting places(Earls or Pirtek) will know the size, as i can't rem.
If it keeps going too long it will need to be rebuilt

[Cuzzo]

On my gt2871rs i dont have an inline restrictor at all unless the turbo has it in the housing?

[YLD-16L]

Most "newer" turbos have the restrictor in the core at the base of the oil feed thread, this would most likely be the case for yours cuzzo.

[30psi 4agte]

Could be a rear turbo seal issue.

Are you sure it is the turbo and not a valve stem seal problem. They can leak oil into the ports and it can pool when the engine is stopped. On start up it is burnt by the hot exhaust. Once the majority has burnt up there will only be a little left to leak through and burn continuously (because of the leaking seal)
This depends on the how bad the seal/seal are. Bad cases smoke like a train all the time.

The only way to tell for sure if it is the turbo or valve stem seals is to pull the exhaust manifold off and see if there is oil in the ports. If it is clear the turbo is your issue.

In that case id look at the rear seal.

First thing first is get the restrictor setup correctly and re-test

[turbo_gze]

How long was the turbo run with the smaller oil drain?

Not long few runs left to idle to sus things out then I towed it home from the workshop.

you'll find a turbo (unless really shagged) will emit smoke at idle and not when running as there is no internal pressure in the turbo at idle, making it easier for oil to seep past the seals/bushes.
i filled a fitting with solder and drilled a 1.5mm hole in it to restrict the oil feed to my t25 (placed on turbo end), solvered my smoke issues. though i have not used a ball bearing turbo, i beleive they can use as small as a 0.8mm oil restrictor. (someone will comfirm this i am sure....).

Did you just use normal solder that you use to solder wires etc?

Could be a rear turbo seal issue.

Are you sure it is the turbo and not a valve stem seal problem. They can leak oil into the ports and it can pool when the engine is stopped. On start up it is burnt by the hot exhaust. Once the majority has burnt up there will only be a little left to leak through and burn continuously (because of the leaking seal)
This depends on the how bad the seal/seal are. Bad cases smoke like a train all the time.

The only way to tell for sure if it is the turbo or valve stem seals is to pull the exhaust manifold off and see if there is oil in the ports. If it is clear the turbo is your issue.

In that case id look at the rear seal.

First thing first is get the restrictor setup correctly and re-test

I doubt it being the valve stem seals as everything was fine when it was supercharged.

When I give it a hit you see a bit of smoke come out of the tailpipe. Blackish with Blue.

But I will give this restrictor thing a try.