Can blown turbo cause crankcase pressurizatiion?

[AL92]

Not sure if anything has to do with the other but my turbo is pretty bad in my 91fwd.It grinds on the sides of the housing and seems to be blowing a lot of oil thru the intercooler pipes. Not really noticing much out the exhaust though. Also it seems to be forcing oil out the oil cap and making the dipstick come out.
I ran a breather out of the engine to the ground from valve cover just now and also reconnected the pcv.I had it straight fitting to catch can and then catch can back to valve cover.
I think may also be getting some oil seeping thru other places.
Is there any other thing that can pressurize the crankcase if there are no blockages in the valve cover breather tubes? My engine seems fairly healthy and dont' seem to see any smoke buring from the rings.
I have another turbo on order that should be good.Right now I can't boost past 10 and it makes some bad noises when it does boost.

 

[huafist]

Even with as much play as your turbo is exhibiting, I don't see how it could possibly allow that much pressure into the crankcase. I suspect your problem lies elsewhere.

 

[skinnykenny84]

from vfaq.com

Dipstick popping out - happens due to crankcase pressure pushing the dipstick up:
A good running motor will blow out a dip stick with a shriveled hard rubber seal
A dead motor (lots of blow by, busted pistons) will blow out a good dipstick
A 1/2 dead motor will blow out a 1/2 dead dip stick
Depending on the actual cause and the severity, the fixes can be:
A spring/wire to hold the dipstick down
Pinch the tube at the top a bit
Get a new dipstick
A full engine rebuild or new pistons
If it blows out under boost with a glowing red turbo and manifold, it makes a nice engine fire. If it happens even once, figure out the cause and fix it.

Are you familiar with vfaq.com? and can a brother get a lil rep point ever now and then???

 

[skinnykenny84]

also yes, your turbo is bad

 

[AL92]

I had a spare dipstick so put it in there. I also put pcv back in and took off catch can just running a hose from valve cover down to road.
I decided to drive the car still but keep it out of boost. Would think this would help short term as wouldn't think it would be as bad if the turbo is not boosting.
I have another better turbo coming and will throw it on there.
I think the engine is sound it don't blow any oil out the back really and don't use hardly any oil either. Its possible the oil in the intercooler was from previous only owned the car a couple of weeks and mabye pcv was shot or something.
The turbo is shot for sure though and does only get maximum 10psi and sounds real noisy.
I still can't figure out why I only got 14 in hg of vacuum.Its very steady really but have some weird idle surge.
I have another isc in mail also.
I still suspect a big boost leak.I have changed injector seals, will change out tb throttle seals, tb gaskets, j pipe gasket ,blow off gasket and check intercooler hoses and intercooler. Need to find my boost leak tester!
So hoping the solution is in there somewhere.
Also I threw a new dipstick had lying around on there and think its staying in there.I also took off wire cover so can see if my new oil cap is leaking into the valve cover inner area.

 

[skinnykenny84]

first thing is fix the dip-stick problem, then put a turbo on it, .... then do the boost leak test.
also read the vfaq and look at the catch can, it should be as simple as the one on there. yours sounds kinda sketchy????? just pick at turbo up on the classifieds for cheap till you get everything straightend out.

 

[AL92]

I have rre catch can used it on my former 92 talon awd turbo. I know how to hook one up.You either just run the valve cover line that goes to your intake pipe to the catch can and block intake pipe nipple or you put a straight fitting in the pcv place,block pcv hose to intake manifold and run that line to catch can and out the other side back to valve cover.
I put in a brand new dipstick ,so far good but not going into boost. Another 14 b has already been ordered and will do boost leak test shortly as really want to find reason for the 14 in hg max vacuum. I thought timing gears might be off but they look ok mabye have to check timing on under the front cover.

I bought this car dirt cheap and plan on selling it anyway just like to fix things for the next guy and then feel good about the car.
I am using the profits for my 97 talon and my 99 trans am.Those are my serious cars.
Will give an update after turbo and the boost leak test.

 

[skinnykenny84]

I would think the turbo is causing the loss of vaccume but would like another opinion on that. anybody else?????

 

[4wd-Eclipse]

I would think the turbo is causing the loss of vaccume but would like another opinion on that. anybody else?????

Would you please EXLPAINE this

 

[skinnykenny84]

Would you please EXLPAINE this

are you being a smart a$$ or are you serious? Hard to tell these days!
I am not a 100% sure being that I cant see the car and from the info provided, thats why I asked for a second opinion. But, it seems to me that if you have air passing through a bad turbo (boost or vaccum) and its a bad turbo it would throw off that reading.

 

[dsm-onster]

Ok. I'm sorry but this is funny... I really am not here to offend anyone. So don't take that as a flame even in the slightest sense.

Nevertheless, no a good turbo usually takes you out of vacuum and puts you in boost during acceleration. If a compressor wheel strikes the compressor housing it iwll slow down. It will be harder to turn this would increase vacuum if a difference in idle intake manifold pressure is even remotely measurable.

Blowing out a dipstick is a symptom of worn out rings. This would cause a loss in vacuum as well.

 

[skinnykenny84]

man I know a good turbo takes you out of vaccum! thats called boost! I dont think we are all on the same page. I thought he meant he wasnt pulling enough vaccum @ idle. There for wouldnt a bad turbo make less vaccum. Unless his entire dip stick problem is related to his motor going bad wich will make less vaccum and blow the dip stick out.

 

[dsm-onster]

man I know a good turbo takes you out of vaccum! thats called boost! I dont think we are all on the same page. I thought he meant he wasnt pulling enough vaccum @ idle. There for wouldnt a bad turbo make less vaccum. Unless his entire dip stick problem is related to his motor going bad wich will make less vaccum and blow the dip stick out.

At idle, if a compressor wheel strikes the compressor housing it will slow down. It will be harder to turn this would increase vacuum if a difference in idle intake manifold pressure is even remotely measurable.

I suggest looking at each symptom individually...

Have you done a boost leak test? If you have a leak this will give the symptom of a loss in vacuum at idle...

 

[AL92]

Yeah I have low vaccum at idle..around 14 in hg.
My motor don't blow oil out the pipes though so figure its not rings.I haven't done compression on it though.
I get around 10psi on the hurting turbo but only 10.can't get any higher.
Another used one is in the mail.
I still have to check for boost leaks and hope to figure out the low vacuum thing.I might have timing out on the timing belt ,the sprockets are lined up but not sure if the mark on crank is.
I also have to double check motor timing although these factory balancers separate way too easy..bought a nice fluidampr one for my 97 2.4 build. They are very nice pieces.

 

[dsm-onster]

Yeah I have low vaccum at idle..around 14 in hg.
My motor don't blow oil out the pipes though so figure its not rings.I haven't done compression on it though.
I get around 10psi on the hurting turbo but only 10.can't get any higher.
Another used one is in the mail.
I still have to check for boost leaks and hope to figure out the low vacuum thing.I might have timing out on the timing belt ,the sprockets are lined up but not sure if the mark on crank is.
I also have to double check motor timing although these factory balancers separate way too easy..bought a nice fluidampr one for my 97 2.4 build. They are very nice pieces.

Causes of low vacuum:

1) Worn rings
2) Boost leak
3) Non- stock cam timing or non-stock cams

 

[1SloColt]

When I blew out a turbine seal with my scm61 I started getting a massive amount of blowby. I spoke with several people and we finally came up with this theory, though not sure it holds but it seems plausible, that the boost was making its way into the crankcase through the oil return line. Since the turbine seal was blown to all shit the compressor seal musta given up too slightly, because I had pretty severe shaftplay, and let boost go past it through the center cartridge, and since the turbine seal was blown all to hell the oil is gonna take the path of least resistance more often than not.

 

[skinnykenny84]

At idle, if a compressor wheel strikes the compressor housing it will slow down. It will be harder to turn this would increase vacuum if a difference in idle intake manifold pressure is even remotely measurable.

I suggest looking at each symptom individually...

Have you done a boost leak test? If you have a leak this will give the symptom of a loss in vacuum at idle...

So are you saying a bad turbo can absoluty not cause a boost leak and or loss of vaccum. Im not just talking about this bad turbo (wheel hitting comp housing) I mean in general. You know what I mean, turbos can go in diff ways. I think if nothing else it indirectly can.
SCHOOL ME

 

[skinnykenny84]

and I guess I have to use this thread to get an answer, why isnt my timeslip info showing up on the timeslip page or on each post???? sorry to use your thread but no body wants to return my pm's. Ive asked 2 moderators one of witch this site is founded by??????? if anybody knows the answer lemeknow.

 

[dsm-onster]

When I blew out a turbine seal with my scm61 I started getting a massive amount of blowby. I spoke with several people and we finally came up with this theory, though not sure it holds but it seems plausible, that the boost was making its way into the crankcase through the oil return line. Since the turbine seal was blown to all shit the compressor seal musta given up too slightly, because I had pretty severe shaftplay, and let boost go past it through the center cartridge, and since the turbine seal was blown all to hell the oil is gonna take the path of least resistance more often than not.

That is what I thought MIGHT be possible but didn't mention it becasue I'd never experienced it nor did I think enough boost could be captured through the seals. Great personal experience that should make this guy feel better . He should repace his turbo first and see if this helps everything... Obviously, it is entirely possible that it could!

Replacing rings is a bit more difficult than replacing a turbo.

 

[1SloColt]

I mean its the only theory I and some buddies of mine could come up with. When the turbo was rebuilt all the blowby stopped so something was obviously pressurizing the crankcase.

 

[skinnykenny84]

That is what I thought MIGHT be possible but didn't mention it becasue I'd never experienced it nor did I think enough boost could be captured through the seals. Great personal experience that should make this guy feel better . He should repace his turbo first and see if this helps everything... Obviously, it is entirely possible that it could!

Replacing rings is a bit more difficult than replacing a turbo.

isnt that what I said yesterday?

 

[dsm-onster]

Well every dog has his day... J/K

I just think that a compression test and a boost leak test should be done first. BEFORE anything... There's no way of knowing what's goin on without knowing what's going on...

 

[skinnykenny84]

Well every dog has his day... J/K

I just think that a compression test and a boost leak test should be done first. BEFORE anything... There's no way of knowing what's goin on without knowing what's going on...

why would he do that "BEFORE" replacing the turbo? I think most of his problem is his turbo. I think he should swap that out (since hes already got one on the way) then do a boost leak test.

 

[high klicks]

Just a warning but if your turbo compressor wheel is hitting anything on the intake side, if you have a peices break of they may end up in the engine and then you have a lot more then just replacing your turbo. So if I where you don't run that turbo if thats the case. Get that new turbo fast. But in the mean time see how much psi intake side will hold you may just have a leak somewhere that starts at 10 psi.

 

[dsm-onster]

why would he do that "BEFORE" replacing the turbo? I think most of his problem is his turbo. I think he should swap that out (since hes already got one on the way) then do a boost leak test.

If it's a problem more complicated than a loose clamp then it would be advantagous to repair it while he's doing a turbo swap... Because Heaven knows he needs one anyway.

Also, it's good to know where his problem is. If there is enough of a leak to blow out his dipstick at the turbo seals then he will hear it.

EDIT: please listen to high klicks... an engine ingesting metal is an engine about to lose alot of compression.