leak test, air going into oil

[ceschwede]

Okay, I put my 16G on a few weeks ago, it ran just great untill I started to get a boost leak, so I tested it and found that air is actually going into my oil from the inlet of the turbo. I can hear it bubbling and if take my oil cap off, I can hear it venting. This is a new turbo with only 50 miles on it!!! I could only imagine that the turbo is shot for it to be leaking air through an oil line, but I wanted some second opinions before I called the vendor I purchased it from. Thanks for any help.

 

[honduraneclipse]

check to see if your banjo bolts are properly tourqued with washers

 

[ceschwede]

The nuts are not leaking, they are tight with all new washers. Plus, would that explain how air is getting into my oil pan? I dunno, please fill me in if yes, and I will definatly go back and recheck.

 

[BUCK]

My guess is it's going past the Turbo oil seals & into the oil pan via the Turbo Oil drain line that goes straight to the oil pan.

 

[ceschwede]

So I need to start making a phone call to the vendor for sending me a screwed up turbo huh? Well, thank you for your advice and help.

 

[GTM]

Originally posted by ceschwede
So I need to start making a phone call to the vendor for sending me a screwed up turbo huh? Well, thank you for your advice and help.

Whoosh, I'm missing something here. You have 10-35 psi oil pressure at the turbo seals, at idle you have no boost pressure and little exhaust pressure. I cannot understand how air is coming from the turbo into the oil pan much less hear anything. The oil pan is not full and for sure the crankcase had better not be, as a general rule the outside edge of the largest oil seal will be slightly higher than the full mark. The rest is gasoline vapor and blowby gasses. Unless your oil pump is loose and sucking air (crankcase gasses) and oil there is no way to get bubbles in the pressure oil feed. Before you make that leap into the supplier's face be on solid ground as to what exactly is happening. You certainly can alert him that you are having some problem but not sure what it is. This way he's on notice (get people's names) and you are protected if something is wrong.

Though I've never seen one their could be a casting crack which only involves the oil drain from the exhaust side. But remember you have water jackets in there too. Maybe you could describe how and where you are hearing these noises. Any chance you are hearing the oil draining into the crancase from the top of the head?

Cheers,
GTM

 

[ceschwede]

Well, as I stated, I know that there is air going to the oil from the inlet side of the turbo because I am doing a basic boost leak test by making the thing off vfaq to do pressure leak checks. As I start to pump, there is an obvious bubbling sound, not air in water type sound, but air in something thicker, and if I take my oil cap off and put my ear up to it, I can hear it bubbling and venting. Its not air in my coolant because I have taken the cap off and looked for bubbles, and there are none. When listening throught the oil cap, it is just one of those obvious things, the air is going from the inlet side (via a boost pressure leak tester) and into the oil. The tester only gets to about 5psi and quickly drops back, and there are no other leaks that I can hear through the I/C pipes. Your feedback is greatly appreciated.

 

[GTM]

Originally posted by ceschwede
Well, as I stated, I know that there is air going to the oil from the inlet side of the turbo because I am doing a basic boost leak test by making the thing off vfaq to do pressure leak checks. As I start to pump, there is an obvious bubbling sound, not air in water type sound, but air in something thicker, and if I take my oil cap off and put my ear up to it, I can hear it bubbling and venting.
...
Your feedback is greatly appreciated.

You are welcome.

That was most helpful in understanding that you are in fact getting those sounds. I am not familiar with the Vfaq "thing" (leak tester?) so can't comment on it's effectiveness.

I am taking for granted that when you pressurize the system as you describe that the engine is _NOT_ running. I can say that from what I know of the seal design it does not mean it's defective just because when pressure is applied from the outside going in for it's function is to prevent what's in from coming out. Thus I am not ready to condem the part based on what you have reported with the engine not running and no oil pressure. However, if it's a large quantity of air (subjective) it does mean it's getting past the seal and bushing which is a pretty close fit. But if you have no evidence the seal is leaking oil then your concerns about this aspect are not the problem. Under no circumstances will air be allowed to enter the oil when the engine is running as long as the inside oil pressure is greater. Plus the amount of air you are detecting won't amount to a hill of beans in comparison to what is being consumed by the engine. Now if there is shaft play this is not right and must be addressed.

This seal is used in air conditioning compressors and some water pumps. In the case of the water pump they have been known to suck air when high levels of cavitation occur but never leak a drop of water. I won't go into those ramification since we are addressing your turbo.

So unless the Vfaq article specifically identifies this as a bad sign and gives the reasons it's my opinion this by it self is not enough to condem the turbo.

You stated previously that you had a boost leak, was this the only thing you found? Were you experiencing an actual power loss from the turbo or some other problem? Or were you just checking to see if the installation was good and the bubbles were the only thing you found?

Cheers,
GTM

 

[ceschwede]

Wow, that is really helpful. As far as why I was checking for boost leaks, I started hearing the whining sound that I know from past experiances is a small leak in the I/C pipes, and I did find a leak at the J-pipe which is now fixed. I do not understand how I can actually maintain any pressure in the intake system to check for any other leaks if all the air is going past my turbo and somewhere else that I have no control over. I would like to pressurize my system to at least 10Lbs, but that will not be possible, cause I cant keep it at 5Lbs when Im continuously pumping air into it. I dunno, but you are most helpful in the matter. Oh yeah, the turbo has NO shaft play, in any direction.
Thanks again.

 

[GTM]

Originally posted by ceschwede
Wow, that is really helpful.
...
I do not understand how I can actually maintain any pressure in the intake system to check for any other leaks if all the air is going past my turbo and somewhere else that I have no control over. I would like to pressurize my system to at least 10Lbs, but that will not be possible, cause I cant keep it at 5Lbs when Im continuously pumping air into it. I dunno, but you are most helpful in the matter.

You may not say that when I send you off looking for snipes...

So how about trying to put your pressure _after_ the turbo???

I know the throttle plate should be closed, don't know about the Biss screw position though I would _think_ it needs to be snugly seated if you are not going to pass air through it. Someone on this list had his father helping him and put 45 psi into the system, car hasn't run right since and I've not heard if any of the things he thought were damaged were fixed. I don't know what you are using for a pump but be careful.

Do you have the exact URL for the turbo leak checker so I don't have to go searcing Vfaq.com? I've never had to go through this process on any car so let me get up to speed with what they are trying to establish and maybe I'll have some helpful ideas.

Cheers,
GTM

 

[ceschwede]

The URL is http://www.vfaq.com/mods/ICtester.html That is what I am using except I hooked up a bicycle pump to pump it up. Thank you for being so helpful on this matter.

 

[GTM]

Originally posted by ceschwede
The URL is http://www.vfaq.com/mods/ICtester.html That is what I am using except I hooked up a bicycle pump to pump it up. Thank you for being so helpful on this matter.

Ok, I'd seen that before, no mention of the turbo seal.

I see no reason to not by-pass the turbo with your hookup. If you are using a foot pump or a bicycle frame mounted pump you probably can't keep up with the air loss and check at the same time so you are pumping yourself to death and getting no place fast.

So you need an air storage tank that you are thinking you don't have. Look no further for it's in the trunk of your car and other family members cars. It's called a spare tire, you just need a hose and fittings plus some way of controling the pressure. Using a pair of Vice Grips you can pinch off the hose and then have someone adjust the V/G set screw while you let the air out of your own tire. Just remember you got a whole lot of pressure there and if you don't control it you could be in trouble.

You can also use a 3'-5' piece of 1/2" garden hose as a listening device by pressing one end up to your ear and then moving the other end around suspect areas.

Other storage tanks can be made from 2 liter plastic soda bottles, I've used them at 20 lbs for an air brush storage tank but am told the big model airplanes run them up to 100 psi for their retractable landing gears are gas operated. If you decide to test that 100 psi do in a big tub of water so If it does explode it won't break the windows 2 blocks away.

You can mix some dish soap and water in a trigger type sprayer which you can then spray on fittings to see if you have any bubbles.

Remember necessity is the mother of invention so improvise on this stuff.

Keep us posted on what you find.

Cheers,
GTM