silent running

Should be 'Pools' not 'oools'!

Another situation stemming from my recent attempt to fix up my knackered inlet pipe on my MY98 WRX...

It had come loose again at the turbo end and for reasons that I won't go into on this thread, I'd had all the engine breathers BLOCKED OFF for a day or two when on boost - the rest of the time the crankcase-to-PCV line was still directly connected.

Took it apart last night and found the turbo and turbo-to-FMIC pipe full of fresh oil, pools of it sitting at every hose joint. Also there had been a lot of leakage from the entry and exit of the compressor, oil splashed around here and there and pooled under the inlet pipe on top of the engine. FMIC return pipe and throttle body seem clean and dry. Standard recirculating DV seems dry although there's a little oil at the turbo end of the return pipe.

Diagnosis please? Blown turbo oil seals? And if so, how and why? The blocked breathers? I can't see any other way that much oil can have got into the inlet tract. Would this be a permanent problem meaning a turbo rebuild or could it have been solved by opening the breathers up, meaning all I need do is check the oil level, clean up the inlet tract and bolt everything back together?

HELP!

Slowboy Racing

The problem is directly related to blocking of the breathers which is not a good idea.

The oil return on the turbo is subject to crank case compression, it needs to be free from this in order to return the oil to the sump. If it’s not the turbo will not cope with out being able to clear the oil and in turn will go past the seals via the induction which is what I am betting is what’s happened here.

The seals should be ok, the only way to now for sure is clean it up and put it back together, start again with the breathers connected correctly.

Hope this helps.

ZEN Performance

Clean it out, and it should be fine. We've had this before when a customer all but blocked the breathers, and the turbo spat loads of oil into the intercooler. We cleaned the intercooler and no more oil came out, and it's since been fine despite the customer being sure the turbo was fubar.

Jolly Green Monster

iTrader: (4)

what they said... very bad idea blocking the breathers

silent running

LOL well you live and learn. I honestly couldn't think how the compressor side of the turbo and the crankcase could possibly be connected!

I'll get the inlet tract cleanup operation going then, hopefully it should all bolt together fine and that'll be that. Now just waiting until I can afford a new inlet pipe!

Quick question: Is a Samco inlet pipe really just the same size as the OE one, just in silicone? Or is it oversized? I was mulling over whether to fork out for a Samco so at least I can get it to sit securely on the compressor flange. I get the feeling that however many OE pipes I get, they're always going to stretch or tear at the turbo end. I'm now on my third already.

ZEN Performance

the compressor side and the crank case are not connected. the core of the turbo drains it's oil into the carnkcase, when the crankcase pressure is too high, the oil in the core gets forced out into the compressor cover and exhaust housing.

silent running

So kind of 'hydraulically' connected then? HOpefully I should have it running soon.

Welloilbeefhooked

iTrader: (3)

Silent, did the same on mine, or rather the old man kinked the breather pipe I had running down the inner wing.

Had loads of smoke from the exhaust and oil in every part where it shouldn't be.

Been running fine since I sorted it out.

silent running

COol, sounds like I'm in the clear then. I just cracked open the FMIC entry hose and it's full of oil as well, so a good old blast with the carb cleaner and old rags should clear that out....

edit (after a bit of a shakedown):

It now drives OK, no oil anywhere in the engine bay and seems to be running alright, but it's hesitant/slow when building boost. It's also now not hitting its target boost at both my commonly used settings, 1.0 bar and 1.45 bar. Both build relatively slowly to about 0.1 bar less than their intended boost i.e. 0.9 and 1.35 bar respectively.

My immediate thought was that this could be either oil in the boost solenoid or a leaking in the boost circuit. There's no way on my own in my garage I can find a hose that leaks on boost, they all seem secure and no different to how they were before, plus I cleaned them all thoroughly before putting it all back together. Just cleaned out the boost solenoid but there wasn't a lot in it, or its pipes. Just going for a drive now to see if it's cleared the problem, but are there any other suggestions?

What else could cause this kind of underperformance?

Welloilbeefhooked

iTrader: (3)

Any progress on this mate? I'm wondering if the oil is slightly blocking your core and restricting things somewhat. I washed my TMIC out with petrol to get rid of the oil in the core.

Thread hijacking here;

Just noticed that when I turn the ignition off I can here air escaping from somewhere and its lasts around 2-3 seconds. Just wondering if the fact that the smaller of the 2 pipes from the crankcase breather (which has a narrower than 1/2 inch section) isn't allowing enough air to escape fast enough?

Or is it from the turbo spinning down?

Any thoughts?

silent running

Well I THINK I've finally got it sorted. Cleaned out the boost solenoid and all the half dozen vacuum pipes between there and the inlet tract - problem solves. Hits target boost spot on again, whatever the setting. Full load lambda voltage seems much better than before all these problems (back up to 0.84v). I didn't go as far as removing the FMIC because that would have been just something I didn't want to get into. But I did pull off all the joining hoses on the hot side of the FMIC and cleaned out all the pipes and joiners, plus the hot side of the FMIC entry itself. The cold side was pretty clean anyway. Once the weather's warmer and I need to overhaul the bumper anyway, I'll get the FMIC off and flush it out properly. This kind of job was a lot easier with a TMIC!

Sounds like something spinning down and turbos do get noisier if you've a leak somewhere. That's what alerted me to the inlet pipe leak I had in the first place.

The crankcase breather tees off two ways - the top one goes direct to the inlet pipe normally and is often vented elsewhere instead, is actually very restricted. You sound like you've found this out as well. It's not even 1/4" I don't reckon. The side tee goes off to the PCV and is full size to fit 1/2" ID hose. The bit that actually plugs down into the crankcase breather port itself is actually 19mm. I thought of hooking up a big boy 19mm pipe directly into this and just venting it straight out. It's still just a thought though.

At the moment the layout is 1/2" crankcase breather line to catch tank; 1/2" rocker cover teed breather line to catchtank; catchtank to atmosphere via long 1/2" hose to rear axle area. Whether this lets it breathe enough I don't know. Next job is to take the inlet side apart again and see if it's still clean.

Welloilbeefhooked

iTrader: (3)

Do you mean that you are using the larger of the 2 outlets from the crankcase breather for your method? IE with the smaller outlet blocked?

Wayne.

silent running

Yes I figured there's no way it's going to breathe properly through that little pinhole, now that there's no vacuum on it. So I blocked off the top (restricted) connector and use the one that comes out the side, straight into my catch tank. The main thing I'm worried about now is that you've got two 1/2" breathers going into the tank, and only one 1/2" breather going out, on a 4m long hose right out to the back, which must cut 'breathability' as well. After all, you or I wouldn't want to breathe through a 4m long 1/2" pipe. But I don't want exhaust smells up front, so what's to be done?

Welloilbeefhooked

iTrader: (3)

Modified my breathers today.

I have now got the 2 rockers t'd together and running down the inner wing to the front of the car.

The crankcase breather (the plastic part) is now in the bin. It does indeed have a 1/4" bore, hence the bin.

I have used some 19mm pipe that now runs from the engine and down over the gearbox towards the rear of the car. It stops about half way over the box and doesn't seem to give any increase in cabin fumes/smells.

I was thinking about the catch can idea but will see what drips I get first.

Wayne.

jasonius

iTrader: (1)

This is basically how mine has been running for 18mths or so, without any drips, although there is residue in them)..

Back in October I cut them both shorter (were running to rear axle) as first MOT was due (to prevent unwanted attention ) and TBH, I'd never been happy with the way they 'sagged' under the car.

They now run basically the same as yours which I think is better as there's less chance of them getting kinked..

Silent, when I first did this mod I cleaned out the TMIC and pipework with petrol as the core was covered in oily residue, so it may take a while for this to clear from your FM. I take it you know it has the potential to lower the effective octane rating of fuel..

silent running

Well I've also been modding my system again. I have now finished for the time being, now time to sit back and see how it works. I've run twin 1/2" vent pipes over the gearbox just past the gearstick linkage to the first bracket holding the propshaft in place, with a bit of heat sleeving over them in case the exhaust melts them at standstill! Better safe than sorry. No smells so far and much neater than going all the way to the rear axle.

I do like the idea of running the rockers out somewhere else. Next time I overhaul the inlet manifold I might strip those rocker breather metal pipes out from under there. They're in the way of everything.

Welloilbeefhooked

iTrader: (3)

I cut the metal breather pipes out when the manifold was off the other week. Cleans it up underneath.