Club 80-90 Forums

Hi there
I've recently bought a 1990 t25 with a 1.9 wbx engine knowing it needed the engine rebuilding due to dreaded mayo in the headertank so set about this task and rebuilt.
New rings.
New top and bottom liner o rings
New water jacket gaskets
New cylinder head spacers
All cleaned out with heads skimmed and put it back in.
Started running it in and noticed I was still getting mayo.
Drained the oil and bright blue antifreeze started running out.
GREAT.
Took the engine back out and rebuilt and cleaned again.
Engines back in and this time the oil and coolant are still mixing but the sumps empty. It's like the oil is just dissapearing .and the coolant is still like mayo.
Any suggestions ?
Can't find any issues with any components when it's stripped.
I'm just stumped.
Cheers

did you check this,seen a few of these reported failed recently

oil gallery drilling by Paul_Barr, on Flickr

failed

failed plug to oil gallery by Paul_Barr, on Flickr

Hi mate I didn't . I will strip down and inspect this time . Thanks for your help. Are they replaceable ? Or is it a new engine case ?

Leaky oil cooler/warmer? Just thought I would mention it in case you have overlooked it.
Whoops just realised it’s a1.9 ,so I don’t think you have one !

Kiw707 wrote:Hi mate I didn't . I will strip down and inspect this time . Thanks for your help. Are they replaceable ? Or is it a new engine case ?

yes fixable by drilling out and adding a threaded plug with sealant but you may be forced to remove the head stud for access which may break.
worst case is spark erode the snapped stud and then repair plug.

clearly you neec to clean swarf from gallery which probably means removing core plug and flushing.

Legend!
Cheers dude this will be my next port of call

of course it could still be a problem with a lower barrel seal surface not being flat or a head stud leaking into the rocker area but so much loss of oil implies its being pumped into the water system and this can only happen here
one more unlikely possibality is a cracked engine case perhaps if it was frozen with no coolant.

Good luck with finding the source of the oil mixing, you have some good advice already.

I note you say leak of blue antifreeze. I thought the WBX needed the pink G12/G13 stuff, otherwise there'll be problems down the road

937carrera wrote:Good luck with finding the source of the oil mixing, you have some good advice already.

I note you say leak of blue antifreeze. I thought the WBX needed the pink G12/G13 stuff, otherwise there'll be problems down the road

lots of people use blue but you can't mix, as long as its replaced regularly it appears to be ok

Originally the correct antifreeze used to be blue but vw have changed to the pink g13 (I think). Bought the blue antifreeze from just kampers.
Yes mate got some sound advice. Really appreciate it. Seems to be the only forum I've been on that's actually been helpful

Kiw707 wrote: Seems to be the only forum I've been on that's actually been helpful

In all fairness this is very specialist knoledge, not many people are rebuilding WBX and even less have seen this fault, seems like its becoming more common as the WBX cases age.

The sealing faces where the bottom o rings mate need to be cleaned up nicely, the o rings must be placed in nicely cleaned up grooves and I usually use some silicon grease on the o rings. It is also vital that the top of the liners is clean and flat as with the surface of the head where the sealing rings go. If there are any blemishes you can use a very thin smear of something like blue hylomar. And as the other chaps above have said check for cracks around the gallery plug and also around the head studs. The heads can crack allowing coolant into the oil returning to the case but not enough oil gets up there to lose it all that quickly into the coolant. If the oil is vanishing out of the sump it is more likely the gallery seal or the oil cooler if you have one. I often use a bit of valve grinding paste around the bottom of the liner and put it in place twisting back and forth as far as possible to make sure the mating faces are nice and clean and flat, obviously not with the o rings in and clean it up afterwards. Some people use some blue hylomar or similar around the base if the liners as well as the rubber seal. I just use silicon grease . Good luck.