VW Bora 4mo leaking issue

[forsakencrew]

I'm going to hazard a guess and say this has already been covered, but I think mine goes a bit more in depth than most.

Probably about 6 months ago, I was driving home from work one Saturday afternoon, and not 5 minutes from home I heard (and felt) one of the coil packs go in my Bora 4mo (Sep 2001, BDF engine code). Limped it home, ordered a few replacements, and realised she was leaking around the valve cover seals (hence broken coil packs). I replaced those, intake gasket and various other seals, thought that was the end of it.

Realised a week later she was still leaving small puddles of oil (plus coolant) if left parked for an hour or so. Did some more investigating and replaced crack pipe, thermostat & housing, oil cooler, cooler seals, oil filter & seals, oil filter housing seal, plus pretty much every other seal in the area. Took her out again (on another Saturday afternoon, probably 3 months ago), leaked oil all day at work, and decided to spit out half of her coolant (possibly didn't double check my work, bottom radiator hose fell off ). Managed to get it back together in the woolworths carpark and limped her home again.

Since then, she's been sitting in my garage (while I bought another car, Toyota RAV4 ).
I've done a lot of research in the last few months, and all I've come up with is oil pressure switch, which no doubt has never been replaced, and would explain a lot of things. So, I have just ordered a replacement oil pressure switch which I hope will rectify the problem.

Which brings me to my question, is there something I'm missing? Anyone been through this stuff and got to the bottom of it?
Cheers!

[RubAVeeDubDub]

I don't understand how you've come to the conclusion that the oil pressure switch(es) is causing you oil leaks?

If it's never been removed then it's factory tightened and highly unlikely be leaking oil. Even if it was the issue, it'd either be seaping or it'd be gushing out, and the car would be giving you low oil pressure warnings. You're more likely for the oil filter housing to be cracked or not properly fitted than the oil pressure switch somehow leaking oil.

Also - sidenote: Did you order 1 or 2 switches? I'm almost dead certain that the BDE engine's had two oil pressure switches.

If you're having coolant and oil leaks - i'd first be doing a compression test for a head gasket issue or cracked block issue. Would be worth running a test with a vac tester as well.

Maybe you didn't tighten something enough? Or broke one of the many fragile hoses/joiners in the cooling system?
It's incredibly hard to get in and around the front of the engine and it'd be easy to miss a bolt or two, and/or not tighten them enough. I've lost a lot of skin trying to get in and around the front of the bay many times. Misery to work out without the front end off.
The front coolant hose from the engine block to the secondary aux pump is right near the oil filter housing - maybe it cracked or slipped off with all your frolicking about there? Youd be able to see if it was visually leaking but getting the car at temp, turning it off and jacking the back end up.

[dylan8]

Can you trace where it's coming from?
Id be looking at the head gasket if it's coolant and oil together.
Has the coolant overflow bottle got oil in it? Has the oil got coolant in it?

[forsakencrew]

A few things have led me to think its the oil pressure switch. First, after a bit of research, I've read that after a while (~100,000 miles) they go a bit funny and start leaking. The car has been giving me the oil pressure light leading up to the coil packs going, but I thought it was down to the leaks in the valve cover seals. I'm just giving it a go as a precaution at this stage (can't hurt, can it?).
It is just a small leak, only when engine is running. I turned it on the other day to see if she was still starting, left it running for 5 or 10 and she left a drop of oil the size of a 20c piece.
I should get under there again and check over the oil cooler housing. It seemed to be okay when I was under there, and I did take my time putting it all back together.
Did just order one switch. Bentley manual seems to only have one on the diagram in the oil cooler area (I have read that there are two though).
The coolant leak has stopped, it was crack pipe and thermostat housing, which has all been replaced with new bits.
Coolant overflow bottle is not showing signs of oil, clear as anything. Oil seems to be nice and clear as well, no signs of coolant in it.

[RubAVeeDubDub]

The reason I am surprised and skeptical about the oil pressure switch is that I've replaced mine in the past. I've done plenty of work at the front of that engine and I can't see how that oil pressure switch can just start leaking. I did an oil pressure test and cracking that switch after it has 200,000kms of wear wasn't easy. I don't think it's the cause of the leak. Tighten every bolt and clean the engine. If she still leaks then you'll have a decent clue where it may be coming from.

Also I'd recommend a quick check of the oil pressure with a tester. I picked up one off fleabay for only $30 - was a godsend. These engines are expensive to repair and rare to find - you don't want to risk it.

[JustCruisn]

Its not a simple half moon seal ?

[grtuned]

I've seen oil pressure switch leak. Change it it's cheap.
Also possibly replace oil cooler seals if you there.
You can take out the oil cooler complete and replace all o rings.

[forsakencrew]

Its not a simple half moon seal ?

Half moon seal?

I've seen oil pressure switch leak. Change it it's cheap.
Also possibly replace oil cooler seals if you there.
You can take out the oil cooler complete and replace all o rings.

The oil cooler has been out. I replaced the two seals between the cooler and the block, then the two on either side of the oil cooler.

I have spent the morning pulling everything out that I can from the engine, to get in there and have a look. So far theres a fair bit of oil coming through the intake manifold (via PCV), then bone dry from that down to oil filter housing, which is pretty well covered in oil.
I did find that the dip stick tube had come free, but I suspect that could've been knocked out when I pulled the intake manifold off. How easy would that be to pull out, as a side note?

[JustCruisn]

Half moon seal?

VWVortex.com - DIY How to replace valve cover gasket plus cam tensioner gasket / half moon seal

[forsakencrew]

Not sure I can see a half moon seal on the diagrams in the Bentley manual. It doesn't seem to be leaking in the top end anyway.
I'll wait for oil pressure sender to come in, replaced the o-ring in the dip stick tube and report back.