Oil Water heat exchanger (probably) thingy

[BarneyVR6 0]

Last night blasting down the A1 when car suddenly started dumping its coolant. Had a look and it seems to be coming out of the gasket between the block and something which looks like some sort of oil & water heat exchanger. It's right next to where the oil filter mounts. Anyone have any ideas whether this assesment of what it s is right and then Is it straight forward front slam panel, bumper radiator etc. off to get to it?

[Kevin Bacon 5]

Sounds like one of the heat exchanger hoses has ruptured or the HE itself has blown. Oil comes out of the block into the HE and water enters and leaves the HE via the small hoses, so the O ring is unlikley to be the problem otherwise you'd have oil leaking out of it.

 

Kev

[Henny 0]

kevhaywire I think you've hit the nail right on the head there... The aluminium oil "coolers" are a bag'o'sh!te... I have had to do an engine rebuild in the past 'cos a car dumped it's oil into the water thru a crack in the "cooler"...

 

They're not even that good at cooling the oil either. Dump it and get a mocal one instead...

 

Depending on which engine you've got in your C depends on how difficult it is to replace. They're not expensive if you don't want to go the Mocal route.

 

On a 1.8 16V it's not difficult and you don't need to remove much apart from the oil, coolant, oil filter BIG nut under the oil filter and the pipes which attach to the cooler... It's tight, but not too difficult...

 

On a G60 things get a bit more interesting! :?

 

Drain the coolant system

Drop the oil into a suitable container and recycle like a responsible person... :lol: (public service announcement for the day!)

Remove the boost return plastic pipe and the 2 pipes for the intercooler.

Remove the charger outlet.

Remove the battery, grill and driver's headlight so hhat you can get access...

Undo the 4 10mm head screws on the corners of the rad fan cowling and undo the wiring connector to the fan. The fan + cowl can now been removed intact giving you access space to the filter and "cooler"...

Disconnect the 2 water pipes to the cooler. Do this BEFORE the next stage else the cooler keeps moving about and it's a pain in the butt to get the water pipes off! (I speak from experience here! :roll: )

Remove the oil filter and above it there's a BIG nut on the thread (think it's a 30mm :shock: ) that you remove to take the cooler off.

 

Putting it back together is roughly the reverse of getting it off, except you add the oil at the top of the engine and the coolant goes in by the top hose of the Rad into the rad first to avoid air locks! 8)

 

If you're handy with a ratchet and spanners you should be able to do this in about 2 hours... If you've not gone this deep into the engine bay before you should still be able to do it with a bit of cursing, a few bruised knuckles and about 6 hours... :D

 

I've no experience with the other engines in C's so I can't comment on those...

 

Good luck! :D

[spoier 0]

Or for a cheaper cooler solution, I believe the entire oil cooling system including the sandwich plate from a Volvo 740 turbo bolts right on to any A2 (from what I've heard - going to try it soon)

 

Skye

[Rams 0]

spoier, whats A2? I am needing an oil cooler for my vr.

[Kevin Bacon 5]

spoier, whats A2? I am needing an oil cooler for my vr.

 

A2 = MK2 Golf/Rabbit.

 

Use a new Mocal, I wouldn't personally fit a used oil cooler. You don't know what might be inside it that could contaminate the engine.

 

Cheers

Kev

[BarneyVR6 0]

Henny, it's a VR6 so it should be fun. Hopefully I should be able to get to it if I dismantle the front end. Will check if it's one of the hoses first though I think. I think if the unit had blown it would be leaking water into the oil or oil into the water and it wasn't.

[Kevin Bacon 5]

spoier, whats A2? I am needing an oil cooler for my vr.

 

You need one of these.

 

Excuse the state of my car and the crudeness of the brackets, but it's held very firmly in place and is deadly effective.

 

Kev

[Henny 0]

Henny, it's a VR6 so it should be fun. Hopefully I should be able to get to it if I dismantle the front end. Will check if it's one of the hoses first though I think. I think if the unit had blown it would be leaking water into the oil or oil into the water and it wasn't.

 

I guess I should have guessed that from your name! :oops: :roll: :lol:

 

Think I was half asleep when I wrote that post! :?

 

The unit can fail in one of three :shock: ways...

 

Internal failure of oilways resulting in oil exiting engine into the water system and blowing the cap off the expansion tank (this is what my old golf did which then needed an engine rebuild!)

 

External failure of waterways resulting in water escaping into the outside world (sounds like what you have) there should be no contamination of water/oil systems with this failure, just a wet patch on the floor!

 

External failure of oilways resulting in oil leak. This is most uncommon and tends to be just the rubber O ring failing causing an oil leak... Again, no contamination of oil/water systems should happen with this failure...

 

If you've just got a wet patch and your oil and water don't have "Mayo" in them then I recon that you've cracked the water jacket part of the cooler and that's why it's leaking... It oculd also be one of the 2 waterpipes though, or even one of the spring clips which hold the pipes on... Whatever you do, replace the spring clips with either new ones, or a pair of jubilee clips so you don't risk another leak! :D

[G60 0]

spoier, whats A2? I am needing an oil cooler for my vr.

 

A2 = MK2 Golf/Rabbit.

 

Use a new Mocal, I wouldn't personally fit a used oil cooler. You don't know what might be inside it that could contaminate the engine.

 

Cheers

Kev

 

used cooler should be fine if you let parts washer run through it over night.. unless there are chunks of metal or something but if you clean it out and shake it around and run parts washer through it then anything that would come out while running it should come out then... but you're right better safe than sorry.

 

A2 is a golf over here too... only A1s were rabbits ;)

[BarneyVR6 0]

Well took the front end of my car to bits today and discoverd the problem is the pipe from the oil cooler to the block has burst. Going to get a replacement. Does anyone know what the flow is. I would guess water would go into the cooler then into the block. Is this right? Just thinking there could be a further problem that's caused that pipe to go.

[Henny 0]

If you've already got the car apart enough to change the pipe, it's worth also changing the cooler... £20 (ish) could save you a lot more if the cooler finally does let go... :?

[BarneyVR6 0]

Do you know how it comes off Henny? Appears to be attach a big socket onto the bit that sticks out and turn just like a filter, that right?

[CazzaVR 0]

Got any pics of this? Got coolant leaking out of the cylindrical thing at the back right of the engine- sound like the same thing, directly behind the coil pack- is this the oil cooler or water pump? Is it easy to replace?

 

Cheers!

[Henny 0]

Do you know how it comes off Henny? Appears to be attach a big socket onto the bit that sticks out and turn just like a filter, that right?

 

Dunno on a VR6... If it's the same as the 4cylinder cars (and I think it is) you take off the oil filter and there's a 30mm (IIRC) nut on the thread above where the filter went. Remove this and the cooler then slides off the threaded center pipe. Make sure you also change the rubber ring/seal on the top of the cooler else things will get very oily in your engine bay! :roll: :lol:

 

If this doesn't sound or look right, lemme know, as I say, I've never worked on a VR before, but I can look into some of my documentation I've got and work out how to do it if needs be... 8)

[BarneyVR6 0]

Andy not too sure about yours as yours is a later version of engine to mine. Is the bit that's leaking driven by the fan belt? If so that's your water pump.

 

My oil cooler is located on the front face of the block directly in the centre. It has two water pipes attached and is fixed to the block. Right next to it is the oil filter.

 

Henny they do appear to be joined somehow, have no idea about the insides of the oil filter housing as I have not yet dismantled it so I couldn't tell you if it sounds right or not. Don't have a garage so local one did my oil change. Planning to leave it in anyway as new cooler is £100 so going to just replace 2 pipes and see how it goes. If I need a new cooler then I'll just have to take it to bits again, wasnt a big deal.

[Mike Edwards 0]

To remove the cooler on the VR6, just undo the really big nut at the front. It clamps the whole thing on the block. Leave the filter alone.

 

The hoses should be easy to replace if one has already split, has you don't have to woryy about draining the coolant. :D

 

Take them off before you remove the cooler, as one of the hoses attaches to a plactic pipe not noted for it's longevity.

 

BTW. The term cooler is a misnomer - it's there to help the oil heat up faster, so if you do fit a seperate cooler, make sure that it has a thermostatic flow-control valve and that you leave the "cooler" in place.

 

Maybe not a problem if you live somewhere warm and never do short journeys, but otherwise you're going to wear your engine out faster...

[Henny 0]

Mike? Have I been barking up the wrong tree with what I've been saying then? As I've said from the start of this thread, I've never had, or worked on, a VR but I'm interested (ok, sad I know) in whether I was right about it being similar/the same "cooler" as the 4 cylinder cars. You've got both, so you're most likely to know! 8) :lol: 8)

 

And yes, I am envious of you having 3 Cs! :lol: 8)

[CazzaVR 0]

Barney,

 

Went to VW and the bit I need is an 'additional' water pump. It's around £60 :? , but looks easy enough to fit myself :)

 

Cheers

[stu 0]

Andi, do the stealers have a random number generator when quoting prices?!!

I have just had to replace the additional run on pump, because of a leak, and was quoted £192!!!!!

I eventually got a 2nd hand one for £60, though.

Easy enough to change, just a bit fiddly.

[CazzaVR 0]

Stu, seems like it! :mad: I've heard about prices for other things also that have a huge discrepancy with prices I've been quoted- thankfully all in my favour :D

 

Does seem strange though.....£192 is a complete rip off!

[stu 0]

It's so annoying. I live near 2 stealers, and i've started phoning both to get prices, as neither are consistent! (Apart from consistently expensive and unhelpful, that is!)

[Kevin Bacon 5]

Mike? Have I been barking up the wrong tree with what I've been saying then? As I've said from the start of this thread, I've never had, or worked on, a VR but I'm interested (ok, sad I know) in whether I was right about it being similar/the same "cooler" as the 4 cylinder cars. You've got both, so you're most likely to know! 8) :lol: 8)

 

And yes, I am envious of you having 3 Cs! :lol: 8)

 

No you're not barking up the wrong tree. VR6s just have seperate oil filter housings (enviromental reasons - disposable elements and all that bollox) and so don't have screw on filters that attach to the oil cooler as on 4 cylinder cars.

 

Further to Mike's comment on the cooler being a misnomer, the correct terminology is 'Heat Exchanger'.

 

When the engine is cold, hot water 'exchanges' it's heat with the cold oil's, err, coldness, therefore warming up the oil.

 

When the engine is hot, hot oil 'exchanges' heat with cooler water and thus a symbiant circle is formed.

 

I'm not envious of anyone having 3 Cs. 3 time as much maintanence, tax and MOTs! One is more than enough for me!

 

Kev

[Mike Edwards 0]

:shock:

[Mike Edwards 0]

£ lots of MOT, tax and insurance is the down side, but being a mechanically inclined saddo, the maintenance is the good bit (apart from thrashing them along the local rural a-roads that is...) :D