Coolant loss...

[HairyDave]

As stated in prior posts, I've just bought a v70 2.5T, but it has a little problem with a coolant loss.
At first, I noted a hissing sound form the cap on the expansion tank, and seeing the cap was at a slightly jaunty angle, I had a quick look and found the tank was looking stressed and hairline cracks visible. I replaced both the expansion tank and cap with genuine items but today found the newly renewed coolant had gone down again.
On checking the oil level for signs of use, I noted a slight "mayonnaise" on the bottom of the dip stick. Oh F**K.
However, i've seen postings about radiators leaking oil/water, but wondered if there was anything i could do to test this?
Are there any other things that could cause a diminished water level? From the looks of it, the thermostat seems to have been replaced and there are no sighns of any water leasking when it is stood.
I removed the cap to top up with water after it had been stood for 8 hour and there was still pressure in the system, but when topped up and after about 15 min of varied running I could see steam whisping from under the bonnet.
Upon starting from cold, there is a bit f white smoke, but thought this was just the Cat warming up.
Also there is a swishing noise to be heard inside the otherwised silent cabin when first started up. There is no moisture around the passenger area or radio.

Any help would be appreciated before starting on the head gasket, for which i've just printed off a 70 page SBS for dismantling and re-assembling

with thanks, David

[Yosser]

Mayo on the dipstick is quite common (and nowt to worry about usually), it's caused by the dipstick tube being in the cold air away from the block.

If you've got mayo in the header tank, thats a whole other story...

There's no substitute for fixing things properly, but FWIW as leak sealers go K-Seal gets a very good reputation.

[HairyDave]

FWIW? Sorry, never come across this before...

Has anyone actually tried this stuff before? does it really not clog your internal passageways? Surely any narrowing would intensify heat, therefore cause this stuff to coagulate?

David

[mightywolf]

FWIW = for what its worth. It could just be a leaking pipe. Have you noticed anything on the floor after its been stood? Although my mate had a similar problem. A pipe was leaking from around the back of the engine somewhere but it wasn't leaving a puddle on the ground, just using loads of coolant. Turned out the split in the pipe was only opening up while the car was running (as it was under pressure) so not obvious and very hard to find.

[HairyDave]

Cool! That's the sort of thing i was looking for! The nice, simple things to look for! you guys are the experts, ( experience breeds knowledge..) and so thanks for helping me in the ritght direction.

Keep it coming, David.

[The Flying Moose]

Like mensioned above mate the first and best thing to do is an extensive visual check as that will either draw out a simple cracked hose or confirm your hoses etc are in good condition.

[Flatout Phil]

Take the car to any reasonable garage and they will do a gas check on the header tank - essentially, it allows the expansion gasses to bubble through an indicator fluid to show if combustion gasses are leaking into the coolant. Last time I had it done it cost a fiver - but that was ten years ago - so assume about £15/20. My hunch is a head gasket I am sorry to say :(

[Yosser]

Has anyone actually tried this stuff before?

Yes. I have, and I've read multiple good reports online.


does it really not clog your internal passageways?

No, not really. It's not like some other leak sealers which can clog up.

That said, there is no substitute for a proper diagnosis and repair.

[Clan998]

As stated in prior posts, I've just bought a v70 2.5T, but it has a little problem with a coolant loss.
At first, I noted a hissing sound form the cap on the expansion tank, and seeing the cap was at a slightly jaunty angle, I had a quick look and found the tank was looking stressed and hairline cracks visible. I replaced both the expansion tank and cap with genuine items but today found the newly renewed coolant had gone down again.
On checking the oil level for signs of use, I noted a slight "mayonnaise" on the bottom of the dip stick. Oh F**K.
However, i've seen postings about radiators leaking oil/water, but wondered if there was anything i could do to test this?
Are there any other things that could cause a diminished water level? From the looks of it, the thermostat seems to have been replaced and there are no sighns of any water leasking when it is stood.
I removed the cap to top up with water after it had been stood for 8 hour and there was still pressure in the system, but when topped up and after about 15 min of varied running I could see steam whisping from under the bonnet.
Upon starting from cold, there is a bit f white smoke, but thought this was just the Cat warming up.
Also there is a swishing noise to be heard inside the otherwised silent cabin when first started up. There is no moisture around the passenger area or radio.

Any help would be appreciated before starting on the head gasket, for which i've just printed off a 70 page SBS for dismantling and re-assembling

with thanks, David

Check the cap on the expansion tank ....mine is letting by slightly at pressure so you dont see any signs of water loss .

Its just going down probably about a litre every 2000 miles. BTW I replaced the expansion tank and cap a year or so ago ...Ivebeen told the caps can give up the ghost !

Id check all the hoses too ... The mayo on the dipstick isnt too much to worry about as Yosser said ... the wifes T5 gets that I think because it never gets a good run out.

Good luck with sorting it

[HairyDave]

Cheers folks.
Did a sniff test. It's the HG. Bummer. I'm now half way through taking it apart, seems quite daunting, but it's just nuts and bolts. At least thats what i'm telling myself! :)
Any idea what the head should be torqued down to?
Also, can only find two nuts holding the turbo to the manifold... the other two seem to be locating dowls? Is that right?
And a really stoopid question, but i could hear the dump valve working, but some young boy racer in me fancies hearing it out loud. Am i right in thinking it has a recirculating type and if so, could i take the pipe off, which one is it and would it naff up my car?
One last thing, the only part to break so far is a 6mm or so pipe in a funny foam cover, sat under the intake manifold. It had obviously been gone for a while as it was in four parts with the end all gunked up in road dust/oil and there is a thinner pipe in with it, also smashed.
A, what is this. And B, where would i find a replacement?

Cheers in advance, Dave

[mightywolf]

Cheers folks.
Did a sniff test. It's the HG. Bummer. I'm now half way through taking it apart, seems quite daunting, but it's just nuts and bolts. At least thats what i'm telling myself! :)
Any idea what the head should be torqued down to?
Also, can only find two nuts holding the turbo to the manifold... the other two seem to be locating dowls? Is that right?
And a really stoopid question, but i could hear the dump valve working, but some young boy racer in me fancies hearing it out loud. Am i right in thinking it has a recirculating type and if so, could i take the pipe off, which one is it and would it naff up my car?
One last thing, the only part to break so far is a 6mm or so pipe in a funny foam cover, sat under the intake manifold. It had obviously been gone for a while as it was in four parts with the end all gunked up in road dust/oil and there is a thinner pipe in with it, also smashed.
A, what is this. And B, where would i find a replacement?

Cheers in advance, Dave

ok.....don't know about the turbo dowels. you have a re-circ valve on your turbo. you can take of the re-circ and blank it off and fit an aftermarket dump valve if you wanna hear the psssst! the pipe thats broken sounds like part of the pcv system. its a common thing to get blocked up and break. you could do with replacing it all including the oil separator thats under the manifold that the pipes should be going into. they trace round the right hand side of the block and back into the intake pipe. contact simon (rufe) on here and he will be able to get you all the parts you need. should be about 70 quid-ish. if you search on the forum there should be a how to on replacing it. will be easy though seeing as you've stripped half the engine anyway!!

[HairyDave]

Right, they're not dowels, but studs with nuts way underneath. Fund them while trying to lift the head...

Cheers, Dave

[Dangerous Dave]

Headgasket change is not too bad a job, I've done mine twice now. Can't remember what torque the head bolts have to be, but get yourself a haynes manual as all the torque settings are in there and the procedure to change the HG, and buy new head bolts (as I reused mine and snapped one off deep in the block :( ) Might as well do the timing belt and water pump too.

[HairyDave]

Headgasket changed, found it had blown between the oil and water way near No.5... Think it was down to a bodged job before as some of the bolts were a bit looser than i'd expect and the was only 3 nuts holding the exhaust manifold on.
It's now all back together, but when i started it up, it seems to be missing slightly. Do you reckon it could be some damp (it was pissing it down when the ignition side went back on) or could it perhaps be the cams slightly out?
Also, no parts left over :) but I do seem to have a pipe left unconnected... :( It is a thin rubbery black pipe with one of those three legged spring connectors on. At the moment, it's sitting beneath the throttle cable with some slack.

Cheers, Dave

[mightywolf]

picture will help if you could put one up?

[HairyDave]

I'll do that when I get back, but it's the pipe that comes from the side of the the turbo, from a little take off int the middle on the engine side...
Think it may go to somewhere around the vacuum tree, but buggerd if I can see where ;)

[Dangerous Dave]

Sounds like it should go to the boost control valve (bcs).

From what you're describing it sounds like the green pipe in the pic below.
http://i150.photobucket.com/albums/s101/bomb192uk/mbcinstallation.jpg
The red pipe in the pic goes to a takeoff on the front of the inlet manifold next to the vacuum pipe for the brake servo.

Hope this helps

[HairyDave]

:stupid: Found where the pipe went to. It was the connection on the inlet manifold. Just below the fatter one that goes to a none return fitting...? Sorry, really don't have a clue with more modern cars. As you may tell with my website, far more into Steam than cars. :)
Thanks for your help though, and that diagram is outstanding, thanks for your time and effort for that... What would the yellow pipe be for?
Found out why it ran like a bag of Shyte... The dizzy was full of water. When I put it together, it was hammering it down, thus why I was able to pour the water from the cap. Can't believe I stripped the engine down again to find this. At least the cams are in time ;)

Attatched is a quick snap of my engine, cleaned and re-assembled.

T'was fun.... Not!

Dave

[Dangerous Dave]

What would the yellow pipe be for?
OK its probably better to explain how the system works, as it gets confusing otherwise.

The red pipe goes to the recirc valve, this valve releases the boost pressure in the intake piping when the throttle flap is closed, thus avoiding blowing a pipe, etc. It works by using the pressure in the intake manifold (throttle flap open) to equalise the pressure against the recirc valve (with the aid of a big spring). When the throttle flap is closed the pressure holding the valve closed drops and the valve opens allowing the output from the turbo to recirculate back into the turbo intake.

The green pipe is a pressure feed for the BCS (boost control solenoid)

The yellow pipe goes from the BCS to the wastegate actuator. The engine ecu uses the BCS (via pre-defined maps and sensor inputs) to send pressure to the actuator to control the output from the turbo. The wastegate is a flap inside the exhaust turbine housing which opens to allow exhaust gasses to bypass the turbine wheel and thus decrease the turbo output.

The blue pipe is an exhaust from the BCS which connects back to the intake piping just behind the air flow sensor (MAF). This is because all the air used to control the actuator is accounted for by the MAF/ECU, so instead of dumping it back to the atmosphere it is kept inside the system (also why the recirc valve is used).

Anyway..... seems like the pipe that you were on about was the recirc valve pipe, and its a good job you've fitted it, as without it the turbo would have not boosted properly (just recirculated all the time).

And what a lovely shiny engine you have, looks fab!

[Flatout Phil]

:stupid: Found where the pipe went to. It was the connection on the inlet manifold. Just below the fatter one that goes to a none return fitting...? Sorry, really don't have a clue with more modern cars. As you may tell with my website, far more into Steam than cars. :)
Thanks for your help though, and that diagram is outstanding, thanks for your time and effort for that... What would the yellow pipe be for?
Found out why it ran like a bag of Shyte... The dizzy was full of water. When I put it together, it was hammering it down, thus why I was able to pour the water from the cap. Can't believe I stripped the engine down again to find this. At least the cams are in time ;)

Attatched is a quick snap of my engine, cleaned and re-assembled.

T'was fun.... Not!

Dave

Well done Dave, a bit of a job there - as I said, thought it could only be the HG because of the over-pressure. Doesn't it beggar belief that some spiv has left bolts and nuts off a previous rebuild - I have known Volvo Main Dealers do this (rarely but enough). Engine looking good. Is that a chromed intercooler pipe - or just well polished?
Phil.

[HairyDave]

Cheers guys, but :redface: I'll let the photo tell the story!
Figured the best way to see if anything was leaking was to make sure it was clean, so I de-greased the head, inlet manifold thermo housing and anything else that came off... Then I got some autosol out. They're ally, so should polish up? Nah, the 200,000 miles of oil stains wouldn't come out, so a quick spray over with said product got them nice and shiny! :D The Intercooler pipe got three coats with a quick flat off with 800 grit W&D between coats. Came up nice.
Used enamel on steam locos for ages, and it shouldn't discolour too quick, but it's a fraction of the price of chrome, or even stainless...

Dave

[HairyDave]

The dreaded water loss is back. It's only done 2000 mile since the HG change. Not happy. The dipsick is full of mayo, but as has been mentioned earlier, i'm not going to worry, but where is it going? I'm talking like 500ml (coke bottle) every 150 mile or so. There is no over pressure on the header this time...
I'm off to investigate now, but will be looking towards the heater, or water pump, or pipework. There's no obvious signs of any of these, but i've seen mentioned that there could be coolant on a panel under the stereo? I've got the ashtray there, so should i be looking there when i take it out, or have i missed the location?

Regards, Dave

[HairyDave]

Had the engine ticking over and moved, tugged, pulled and twisted every hose, pipe and connection I can see. Considering it is minus out there, even a tiny leak should show as a puff under torchlight. Took the ashtray out and nowt there. Pulled back the passenger side carpet and found the attached photo. Any ideas what this staining is from? There's no moisture under the carpet.
Also, there is no oil in the water, last time there was a faint skin in the header.
Something I did notice is that the fan did not kick in. I know it's minus outside, but after standing ticking over I'd expect it to have started up, but my temp gauge is rock steady at halfway. I've spent some time stood in traffic recently, infact, last night I was stood in traffic for a good twenty minutes, and the fan never kicked in. Could this cause the water to disappear?
No, scratch that thought. Of course it would. Any help in finding the fan switch? (thermostat?) Are there any ways to tell if the switch is at fault, or is it a case of jumping across the terminals of the solenoid, and if so, which wires to cross?

Many thanks in advance, David

[Jamest5r]

Just an idea as you have seemed to of checked most things, the 2 pipes that go into the bulkhead for the heater matrix can sometimes leak under pressure while driving but not at idle, they are only plastic connectors and the rubber seals can wear.

[HairyDave]

Hey James(?), checked those by twisting pulling and pushing on them to see if I could get them to leak. Also there is no sign of leakage in the form of staining from the antifreeze. Alas, doesn't seem to be any pipes, but if you can think of any hidden ones, I'd really appreciate hearing about them because I am really puzzled by this....

Cheers, Dave.

[HairyDave]

Alrighty... Spent five hour fitting poly bushes to the front suspension. Yes, there was four inch of snow on the ground and I didn't start till half two, so when i finished it was dark and pushing minus four. My jeans were sticking to the ground... DIY fitting my arse!
Any way, back to the coolant problem, or rather, my overheating problem.
I stuck a screwdriver across the temp sender. No response. Did the same under the relay. No response. Juped the power in, under the relay to the power out(low). Fan runs. did the same to high, fan runs. So the problem would seem to be not the fan, but either the input to the relay, or the relay itself...

Any ideas how to test the relay?

Regards, David

[Mr Sheen]

Have a wee look here on how to quickly check a relay

http://www.askthemechanic.co.uk/electrical/relays.html

[Jamest5r]

Alrighty... Spent five hour fitting poly bushes to the front suspension. Yes, there was four inch of snow on the ground and I didn't start till half two, so when i finished it was dark and pushing minus four. My jeans were sticking to the ground... DIY fitting my arse!
Any way, back to the coolant problem, or rather, my overheating problem.
I stuck a screwdriver across the temp sender. No response. Did the same under the relay. No response. Juped the power in, under the relay to the power out(low). Fan runs. did the same to high, fan runs. So the problem would seem to be not the fan, but either the input to the relay, or the relay itself...

Any ideas how to test the relay?

Regards, David

After i did my last engine swop my fan would'nt kick in no matter what i tried, in the end just run a new lead direct to the battery.

[HairyDave]

Quick update.
My fan kicked in! Also my heater is working!
I took the thermostat out again to check it once more. It was fine. However, whilst re-assembling it I found the jubilee clip on top of the housing had stripped itself. Replace said clip and now it (seems) to be working fine... Just need a couple hundred mile to be sure. Really can't find anything else wrong with it though. Whilst I was at it, I re-checked all the hoses I'd disturbed whilst doing the HG and they were fine.

Just waiting for the post to come (not had anything for 10 days now...) and i can fit my double piston DV instead of the single i ended up with :)

David