90 Turbo

iTrader: (3)

I have been trying to figure out why my car uses oil.
I replaced
turbo
pcv valve
Removed crankcase vent to intake and just used a filter.

It does not smoke.
I inspected the exhaust when replacing turbo and everything was black inside of course but nothing carzy. Although the cat was black inside and the used one i purchased to replace it was a yellow/orange color.

Any way the turbo change was recent so I was driving it today and nailed the gas an smelled oil. Pull over and the dip stick has popped out of place and oil sprayed all over prob a table spoon of oil maybe 2.

I do leak spots on my garage floor. Seems to be dripping from some where on front driverside of engine. I degreased and the oil seems to be coming from somewhere close to ac compressor.

I have done a compresion test and all good 175 185 190 185 all within 10%.


What does the dip stick thing tell me?

Braineack

iTrader: (62)

pressurizing crankcase.

chpmnsws6

iTrader: (12)

You are putting pressure on the wrong side of the piston.

BogusSVO

iTrader: (1)

^^^^^ yep

The block is not venting enough


Or maybe, the seal on the dipstick is just wore out.....

skidude

iTrader: (3)

If the compression numbers are good, where would the pressure be coming from? He said he doesn't have the intake manifold hooked up to the valve cover, right? Unless the PCV valve isn't the right one, of course.

rleete

iTrader: (21)

PCV installed backwards?

BogusSVO

iTrader: (1)

Piston speed = air movement

above and below the crown of the piston.

chpmnsws6

iTrader: (12)

Wouldn't the opposing movement of another cylinder counteract this effect?

This would be why a piece of paper over a good condition engines oil fill will flutter, while a tired engine will blow the paper upwards.

^ back woods blowby test.

BogusSVO

iTrader: (1)

Yep I know that test! Also when you hold a dollar bill at the end of the tail pipe it should flutter out.. If it sucks in the tail pipe, burnt valve

As the piston speed increases it acts more like an air compressor in the crank case, so the over pressurized air has to escape some how, normally a poped dipstick or in realy bad cases blows out the front seal or rear main seal.

Bad PVC or a system that is too small to move the amount of air needed to equlize the pressure.

Drinking straw and garden hose theroy again.

Add in the rotation of the crank, with the axial movement of the piston /rod and you have all sorts of strange air currents in the bottom end.

90 Turbo

iTrader: (3)

Ok so how do I further vent the crank case?

Savington

iTrader: (31)

If you're popping the dipstick with a GT2554R, it's time to replace the motor. Pushing the dipstick up is a sign of major blow-by.

90 Turbo

iTrader: (3)

The dollar bill fluttered. Wierd thing to see did not know what to expect. It kind of pulse up and down a 1/4 of an inch and flutters there.

I also blew in the driver side vent and it caused air to flow out the dipstick tube so with a simple air filter it should have plenty of venting? i guess?

90 Turbo

iTrader: (3)

Actual got a 2560 now at 13psi.

90 Turbo

iTrader: (3)

Wouldnt blow by cause smoke out the tail pipe.
isnt blow by air passing the cylinders thru the rings and presurizing crankcase. I figured a compresion test woud show that?

Braineack

iTrader: (62)

that's because they are connected. but you can only blow about 1-2psi...

90 Turbo

iTrader: (3)

I wrapped a towel around the air filter on the driverside valve cover vent to see if oil was escaping there and drove around for 20 miles getting into full boost many times and the towel was almost completely dry not a drop on it asmuch as a little black smoutes.

BogusSVO

iTrader: (1)

Lets get back to basics.....

Do a leak down test, that will supply more info, and point in areas that need to be looked into.

A compression test is good but a leak down test is better.

Braineack

iTrader: (62)

it's possible the pcv just got stuck and didnt seal correctly during a boosted run. I run check valve in front of my pcv to prevent this accurance.

90 Turbo

iTrader: (3)

I dont have that equipment. I will work on it.
I just dont see how without signifigant smoke I can be burning a 1/2plus quart of oil a tank.
I have no white smoke. A little black when I am in boost and when it is cold out side and I had the other turbo I would get some on start up.

It has never blown the dipstick out before. I have had the new turbo for 250 miles many many boost runs.

BogusSVO

iTrader: (1)

A cheap leak down tester can be had at Harbor Freight or Ebay for $60 or less