Coolant issues nightmare

Zero4 · Post by **Zero4** » Thu Mar 15, 2018 11:48 am

HI all, hoping to get some advise. I've owned the 2.5 Z now for about 4 years and its been plain sailing to be fair, no issues to speak of until now.

I was going through some coolant recently so took it in and a new tank and hose was installed, looked like the old one had perished a little. Drove it for the day and when I booted it a little the pipe blew off the bottom of the tank and pissed coolant everywhere! ok, simple fix, put the pipe back on and ensure its a good fit, Garage sorted it, bled the lines etc... Seemed fine again for a day then this morning when I booted it It burst its coolant again, white smoke / steam so pulled over and had to get towed to the garage ( mates garage ) and now we are a but stumped. It overheats and the blowers run cold even on hot.

Is there any common uses with the coolant system I should know about. Trying to speed the process to find the solution

Thanks

ph001 · Post by **ph001** » Thu Mar 15, 2018 11:59 am

Hmmm, sounds like your cooling system is being pressurised, which head gasket failure can certainly do. A compression / leakdown test with your coolant bottle lid removed should confirm. Forcing combustion gases into the coolant circuit also creates air locks which lead to overheating and cold blowers.

piotrZ4 · Post by **piotrZ4** » Thu Mar 15, 2018 11:59 am

Sounds like head gasket gone and pressurise system. Very common on m54's

Zero4 · Post by **Zero4** » Thu Mar 15, 2018 12:01 pm

mines a 2003 2.5 though this issue was with later facelifts mostly? Is there an easy way to diagnose?

thanks is advance, complete none mechanical mind here.

Zero4 · Post by **Zero4** » Thu Mar 15, 2018 12:03 pm

hoping its not the head gasket, its been trouble free for years.

ph001 · Post by **ph001** » Thu Mar 15, 2018 12:14 pm

Zero4 wrote: ↑Thu Mar 15, 2018 12:01 pm Is there an easy way to diagnose?

Start car up from cold, remove coolant bottle cap and place your hand on top. Get someone to rev car up - if there is a lot of pressure then your head gasket is stuffed. Proper compression / leakdown test will confirm as already mentioned. Changing head gasket not a major problem, would expect circa £200 - £300 from a good indy + £80 ish to have the head skimmed.

rally-chris · Post by **rally-chris** » Thu Mar 15, 2018 1:21 pm

It might be worth replacing your expansion tank cap before any more drastic actions - IIRC the cap acts as a pressure relief valve and if this is not working then the system could be over pressurising (particularly if over filled following coolant replacement and/or air in the system) and causing the hose to blow off.

Chris

Zero4 · Post by **Zero4** » Thu Mar 15, 2018 1:28 pm

rally-chris wrote: ↑Thu Mar 15, 2018 1:21 pm It might be worth replacing your expansion tank cap before any more drastic actions - IIRC the cap acts as a pressure relief valve and if this is not working then the system could be over pressurising (particularly if over filled following coolant replacement and/or air in the system) and causing the hose to blow off.

Chris

I've got the garage to order a new cap just to see, they are gonna do a pressure test anyway but hoping its something simple. Its not had a hard life at all and I'l not one to blast it everywhere, always gets serviced and maintained well so hoping its something small.

Ducklakeview · Post by **Ducklakeview** » Thu Mar 15, 2018 1:42 pm

Does sound like head gasket especially as it's pressurising. Needs proper diagnosis though as stated, using a chemical or pressure test before jumping in.

The head gasket set for these isn't cheap at around £250, but it's worth doing properly if you're having the head off, so I'd be grinding the valves and be replacing the stem oil seals.

The head gasket, cam cover and exhaust manifold gaskets alone are about £160, so there's not much of a saving after by not going the whole hog, especially after another £30 for the head bolt set. Not sure what the labour time is, but I'll check Autodata when I get a sec.

I've got a 3.0 Zed with same symptoms waiting for me to do.

Mike

Nictrix · Post by **Nictrix** » Thu Mar 15, 2018 2:52 pm

Im sure I read this earlier and Marlon had replied saying something about the water pump
Either it was deleted or I am imagining things

Marlon · Post by **Marlon** » Thu Mar 15, 2018 3:28 pm

Nictrix wrote: ↑Thu Mar 15, 2018 2:52 pm Im sure I read this earlier and Marlon had replied saying something about the water pump
Either it was deleted or I am imagining things

I deleted it when the OP mentioned his was a 2003 so not the infamous facelift N52 electric water pump

Nictrix · Post by **Nictrix** » Thu Mar 15, 2018 3:59 pm

Marlon wrote: ↑Thu Mar 15, 2018 3:28 pm
Nictrix wrote: ↑Thu Mar 15, 2018 2:52 pm Im sure I read this earlier and Marlon had replied saying something about the water pump
Either it was deleted or I am imagining things
I deleted it when the OP mentioned his was a 2003 so not the infamous facelift N52 electric water pump

Good to know Im not going mental

ph001 · Post by **ph001** » Thu Mar 15, 2018 4:09 pm

Ducklakeview wrote: ↑Thu Mar 15, 2018 1:42 pm The head gasket set for these isn't cheap at around £250

The Reinz kit is great quality and just over £100.... https://www.buycarparts.co.uk/reinz/743 ... lsrc=aw.ds

Ducklakeview · Post by **Ducklakeview** » Thu Mar 15, 2018 4:17 pm

ph001 wrote: ↑Thu Mar 15, 2018 4:09 pm
Ducklakeview wrote: ↑Thu Mar 15, 2018 1:42 pm The head gasket set for these isn't cheap at around £250
The Reinz kit is great quality and just over £100.... https://www.buycarparts.co.uk/reinz/743 ... lsrc=aw.ds

Just checked with them, that set doesn't include the exhaust manifold gaskets or cam cover gasket. They are £100 on their own retail.

The Elring kit includes them, as well as the inlet manifold seals, those for the oil cooler and vanos gasket.

: 362110800.jpg (43.93 KiB) Viewed 972 times

Mike

ph001 · Post by **ph001** » Thu Mar 15, 2018 4:34 pm

Ah! I think my link above was for the earlier engine anyway now I've double checked. I think the correct Reinz kit part number is 02-33070-03

Avail on Ebay for £144... https://www.ebay.co.uk/itm/Genuine-OE-V ... #vi-ilComp

: head gasket kit.png (143.1 KiB) Viewed 965 times

I still don't think is has everything compared to the Elring kit though. Hard to know as many of the images are generic.

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