Tuned 850 T5 - Split liner or HG?

[pingpong]

Morning all, after getting the 850 T5 to where I wanted it last year it has been quietly working away for me for the last 12 months or so without any complaint. It currently rungs a 16T, downpipe, map etc.

In the last couple of weeks however I have noted that the coolant level has become extremely unstable, when cold it can all but disappear from the tank and when driven hard it fills the tank to the brim, I suggest very close to blowing! Gentle driving does also get some expansion, but only within normal bounds. It's using a small amount but nothing excessive, it seems more like the system is being pressurised based on how hard the car is driven.

If the system is pressurised to the brim of the tank and I switch the engine off it immediately begins to drain with a gurgling sound and the tank returns to normal levels, this will also happen if I crack the tank cap when the car is hot.

Last year I replaced the water pump and thermostat as part of a overall service and of course replaced the coolant. I did the coolant again on Friday paying extra attention to bleeding and ensuring the thermostat was opening correctly (which it was).

I guess at this point I am looking at either a failing HG or even worse a split liner. Can anyone suggest some diagnostic methods to determine this either way?

[claymore]

850 2.3 is very unlikely to split a liner, I'd guess HG

[Shinsplintz 101]

+1 with Colin

What about oil in coolant & visa-versa? You don't mention it. I'd not be driving that car until you've figured out what's amis.

Sniff test will tell you if the HG had gone.

Also found this thread that may help (or not):

http://www.vpcuk.org/forums/showthread.php?19717-Hubble-Bubble-Toil-and-Trouble

Cheers, Morgan

[Tim Williams]

You won't split a liner with an 81mm block with standard rods, as already said it's most likely the head gasket. Get the head skimmed and also change the coolant cap.

[pingpong]

What about oil in coolant & visa-versa? You don't mention it. I'd not be driving that car until you've figured out what's amis.


No sign of either, both look nice and clean (although as mentioned I did change the coolant a few days ago - but I have done a couple of hundred miles since then.)

Thanks for the input otherwise gents.

[Mental Wealth Doctor]

Make sure you've got the right coolant in her. Head gasket symptoms can be caused by the wrong coolant. Also as stated already try changing the coolant cap. Before doing the head obviously. Hope it's not the head mate

[pingpong]

Make sure you've got the right coolant in her. Head gasket symptoms can be caused by the wrong coolant. Also as stated already try changing the coolant cap. Before doing the head obviously. Hope it's not the head mate

Thanks for the comment. I have done some further investigation and found that there is a tiny split in the tank so I'm going to replace that and the cap at the same time. With regard to coolant I wish I could find a definitive answer on what type the car takes, even the Volvo dealer couldn't tell me - I have currently used the blue silicate type from Halfrauds?

[Shinsplintz 101]

.... from the Volvo workshop manual....

LUBRICATION SPECIFICATIONS TABLE
Application Fluid Specifications
Coolant ............................. 50/50 Mix Ethylene Glycol
and Distilled Water
Brake Fluid ....................... DOT 4 Or DOT 4+ Brake Fluid
Engine Oil
Ambient Temperature
Less Than 68 F (20 C) .................. SAE 5W-30 API SH/CD -4 F To 100 F (-20 To 38 C) .......... SAE 10W-30 API SH/CD Greater Than 14 F (-10 C) ............. SAE 15W-40 API SH/CD
Power Steering Fluid (1) ............. Dexron-IIE or Mercon ATF
Automatic Transaxle (AW50-42) ............ Dexron-IIE or Mercon
Manual Transmission (2) ......... Volvo Synthetic (P/N 1161423)
Or Type F/G ATF Wheel Bearings .................... NLGI Grade 2 Category GC-LB Steering Linkage (3)(4) ........... NLGI Grade 2 Category GC-LB Ball Joints (3)(5) ................ NLGI Grade 2 Category GC-LB Weatherstrip ....................... Dielectric Silicone Grease
(1) - At temperatures below -4 F (-20 C) Volvo oil (P/N1161001-1) can be used.
(2) - DO NOT use Dexron fluid in manual transmissions.
(3) - Use low pressure grease gun to prevent seal damage.
(4) - Fill until lubricant squeezes out from the base of seals.
(5) - Fill ball joint until seal starts to swell.

----------------------------------------------------------

I've no idea what halfords put in their own brand coolant...But it looks ok!?!? Suitable for pre 98 cars. Think the trick is not to put an OAT based coolant in the older cars as it has the potential to eat the internals. Silicate based IATs like the one you've gone for are preferable. Allegedly. Christ, I thought engine oil could be a mine field :lol:

[LeeT5]

You won't split a liner with an 81mm block with standard rods, as already said it's most likely the head gasket. Get the head skimmed and also change the coolant cap.


Make sure you've got the right coolant in her. Head gasket symptoms can be caused by the wrong coolant. Also as stated already try changing the coolant cap. Before doing the head obviously. Hope it's not the head mate

What they both said! :stupid: If the cap is leaking (ie, not holding pressure) then the system cannot pressurise, so the coolant will just expand with heat and then fill the expansion tank too much and leak out. Then when its cold, it will almost disappear because your losing a slight amount of fluid each time it gets very hot.
The split tank will cause identical symptoms to a leaking cap, so change them both!!!

If, after replacing the tank and cap, your still losing fluid and the level rises too much (ie, same symptoms, then it's most likely your HG leaking)

You will not be able to perform a Cooling system pressure test or Sniffer test properly until you've replaced the split header tank, so change these first.


Thanks for the comment. I have done some further investigation and found that there is a tiny split in the tank so I'm going to replace that and the cap at the same time. With regard to coolant I wish I could find a definitive answer on what type the car takes, even the Volvo dealer couldn't tell me - I have currently used the blue silicate type from Halfrauds?

The Volvo fluid is 'Pentosin' and is a blue colour. i'd advise you use the correct fluid as using incorrect fluid can have a detrimental affect on the engines internals long term and more importanatly, it can affect running temps.

Just buy it from Volvo! You don't need much and it's not that expensive.

[pingpong]

Thanks for the comments guys, I will let you know the outcome.

[Shinsplintz 101]

http://www.pentosin.net/f_antifreeze.asp

Pentafrost NF.

Can't find a UK supplier. But the Volvo branded stuff can be had for £10/L or less so it's probably not worth shopping about.

[pingpong]

So just to follow this up, changed the tank, cap, thermostat and coolant and no improvement sadly. Its clear to me now that if driven gently the coolant level stays normal, once you start boosting about the level rises dramatically which would correlate with increased cylinder pressures = leaking HG or cracked head.

I've got a head being cleaned up as we speak to next stop HG change. Will do stem seals and valve seats whilst I am there. All needs to be ready for LM24 in a few weeks time!

[pingpong]

So I had a head cleaned up and skimmed and I then fitted it to the car along with a new HG. Also replaced the two large coolant lines, coolant tank + cap, thermostat, gaskets, coolant etc - all Volvo original parts and...... its still got the issue!

31647

31648

31649

I took great care cleaning the block to ensure a good seat for the HG, as well as cleaning all the coolant deposits from the various coolant line fittings. I also carefully inspected each cylinder and there was no evidence of cracking etc. Compression test all ok.

So... what am I looking at now - heater matrix? Radiator? Water pump? Any ideas because I'm stumped!

[LeeT5]

It may help if you explain the symptoms. Have they changed or have they stayed the same?

Now the engine is reassembled, all you can do is retest everything.
So, Coolant sniffer test and Cooling system pressure test.

Both need to done to rule out combustion gases in coolant and excess pressure caused by a leaking head.
Use a thermo probe to ascertain whether the thermostat is opening correctly and then, that the Radiator fans come on.
Ensure Aircon is off when testing.

[Shinsplintz 101]

Have you checked the coolant lines to the back of the turbo? It's just you mentioned it only occurring on boost - perhaps there is an issue with the turbo or the coolant lines.

https://www.matthewsvolvosite.com/forums/viewtopic.php?t=53962

Have a quick read, might/might not prove useful!

Cheers, Morgan

[pingpong]

Thanks for the comments guys.


Have you checked the coolant lines to the back of the turbo? It's just you mentioned it only occurring on boost - perhaps there is an issue with the turbo or the coolant lines.

https://www.matthewsvolvosite.com/forums/viewtopic.php?t=53962

Have a quick read, might/might not prove useful!

Cheers, Morgan

I was just reading exactly that thread! I've changed the turbo return pipe but not the supply pipe, although the previous owner had had it done in the past. I'll definitely get the car up in the air and have a good poke around tomorrow with this in mind.

Symptoms wise if you drive it fairly calmly everything is fine, start using more erpms and the issue appears (coolant totally fills the tank and is purged by the cap). Starting to think this is erpm related (=water pump speed = pumping pressure) than boost pressure.

I'm happy I've done the head regardless as it's stopped using a small amount of oil due to valve stem seals.

Will report back.

[Ettienne]

Thanks for the comments guys.



I was just reading exactly that thread! I've changed the turbo return pipe but not the supply pipe, although the previous owner had had it done in the past. I'll definitely get the car up in the air and have a good poke around tomorrow with this in mind.

Symptoms wise if you drive it fairly calmly everything is fine, start using more erpms and the issue appears (coolant totally fills the tank and is purged by the cap). Starting to think this is erpm related (=water pump speed = pumping pressure) than boost pressure.

I'm happy I've done the head regardless as it's stopped using a small amount of oil due to valve stem seals.

Will report back.

Sounds a bit like waterpump, normal driving normal, driving fast would over heat as impeller was mishapened and inefficient.

Is it a gen pump? Maybe a blocked rad? Correct head gasket?

[LeeT5]

Sounds a bit like waterpump, normal driving normal, driving fast would over heat as impeller was mishapened and inefficient.

Is it a gen pump? Maybe a blocked rad? Correct head gasket?

Definately not! The car would overheat in minutes and boil itself over, even whilst gentle driving.

[Ettienne]

Definately not! The car would overheat in minutes and boil itself over, even whilst gentle driving.

My s60r didn't, drove normal sat 45 minutes running for mot and drove home, when you boosted it it got hot.

Cause mishapen impeller on the waterpump, it wasnt efficient at moving water and was a "Halfords special" I thought it may have been a plastic one that fell off but it was just a rubbish metal impeller

[960kg]

My s60r didn't, drove normal sat 45 minutes running for mot and drove home, when you boosted it it got hot.

Cause mishapen impeller on the waterpump, it wasnt efficient at moving water and was a "Halfords special" I thought it may have been a plastic one that fell off but it was just a rubbish metal impeller


Very true .......even if the water pump did hardly work the coolant still circulates due to the Thermo Siphon System (Effect) which all engines have built in.

Which is so long as the thermostat is open the water will circulate from the top of the rad to the bottom etc. .....hot water rises cooler water sinks.

If this type of system was not operational when turning off the engine the coolant would boil due to it not circulating.

But when booting it ...a different matter as said.