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Have I just blown a head gasket ??
Posted: 10 Dec 2012, 21:10
by cruachan
Hi,
I changed the coolant in my van today and everything seemed to be going well. However, this evening I thought I'd just take a peek underneath to make sure nothing was leaking. I wish I hadn't. There is a steady drip of coolant and as far as I can make out it seems to be coming from the head to block join on the left hand cylinder bank.
I gave the van a good run after I had finished the job earlier today and the temp guage never went past halfway, however the red light on the temp gauge did flash but when I got back home I switched off then re-started and the red light was out. I've checked the oil and there is no sign of emulsification, likewise in the header tank. It's a long long time since I last did a head gasket on anything let alone a waterboxer but I'm wondering if I've just knackered one of them? There was no sign of leaks when I got back from the test drive but the engine is now stone cold so I don't know if now everything has "shrunk" in the cold the gasket has started to weep. Do head gaskets weep? I thought if they let go it was pretty obvious right away.
Any thoughts would be greatly appreciated.
Re: Have I just blown a head gasket ??
Posted: 11 Dec 2012, 06:38
by Aidan
water jacket seals do weep, and weep onto exhaust so evidence evaporates
panic not just keep an eye on coolant levels and check under regularly till you find evidence of leak or hopefully not, if you've changed the coolant it'll likely take a few runs/temp cycles before it's fully full and steady, as long as darlek cap works then it self tops up as required and you only have to check the top up tank level
Re: Have I just blown a head gasket ??
Posted: 11 Dec 2012, 09:33
by Ian Hulley
On a late cooling system a leaking thermostat housing can also drip from the jacket seal, so it's important you find the real leak. Check the 2 bolts that hold the housing to the head ... the collars they pass through are mild steel and they rust, cracking the housing and breaching the seal.
Good luck, Ian.
Re: Have I just blown a head gasket ??
Posted: 11 Dec 2012, 17:21
by cruachan
Hi,
I've had a good look today and I think it is the water jacket seal that's weeping.
This morning ( Baltic freezing ) there was coolant lying on top of the block along the line of the seal. I dried everything off completely and could actually see the coolant begin to weep out again. Started up and coolant re-appeared immediately but this time on the right hand side of the engine as well! Warmed the engine until gauge half way , coolant more or less stopped appearing on the top of the block but was still dripping a bit underneath but quite slow.
Let the engine cool down again and coolant started to re-appear around the water jacket seals again.
So what to do? Do you think it will gradually "cure" itself? It 's only since changing the coolant that this problem started and I'm still a bit worried that the engine got a bit hotter than it should have during the change possibly causing damge.
Thanks for the info.
Re: Have I just blown a head gasket ??
Posted: 11 Dec 2012, 18:14
by kevtherev
cruachan wrote:Hi,
I've had a good look today and I think it is the water jacket seal that's weeping.
This morning ( Baltic freezing ) there was coolant lying on top of the block along the line of the seal. I dried everything off completely and could actually see the coolant begin to weep out again. Started up and coolant re-appeared immediately but this time on the right hand side of the engine as well! Warmed the engine until gauge half way , coolant more or less stopped appearing on the top of the block but was still dripping a bit underneath but quite slow.
Let the engine cool down again and coolant started to re-appear around the water jacket seals again.
So what to do? Do you think it will gradually "cure" itself? It 's only since changing the coolant that this problem started and I'm still a bit worried that the engine got a bit hotter than it should have during the change possibly causing damge.
Thanks for the info.
No it won't cure itself.
You are about to enter a world beset by dragons.
Seal replacement can be a nightmare.
It can be straight forward.
Will you be doing the work?
What year is the engine?
Re: Have I just blown a head gasket ??
Posted: 11 Dec 2012, 18:26
by cruachan
I will do the work myself. It's a 1.9 dg.
Give it to me straight!
Re: Have I just blown a head gasket ??
Posted: 11 Dec 2012, 18:43
by kit
K seal and forget about it
Re: Have I just blown a head gasket ??
Posted: 11 Dec 2012, 18:47
by Aidan
k seal as temporary bodge till inclination to do the job increases
I k sealed mine 3 years ago, still running, (had a waterpump in that period) but tbh the weeps on Edna not too bad to start with just numerous, about 1-2ml/mile overall loss
Re: Have I just blown a head gasket ??
Posted: 11 Dec 2012, 19:55
by kevtherev
early or late DG? (ie pre 86 or after)
Re: Have I just blown a head gasket ??
Posted: 11 Dec 2012, 20:59
by cruachan
Van's 1990 but not on original engine so not sure
Re: Have I just blown a head gasket ??
Posted: 12 Dec 2012, 07:25
by kevtherev
the engine number would help you there.
engine out, makes the job easier.
The exhaust studs will cause the biggest headache if they start snapping, thats why engine out is easier.
Use heat on the cylinder head stud nuts and crack them off one by one.
if the gasket faces are badly pitted then smear JB weld onto the faces and wipe the excess off
use the VW sealant and gaskets and re assemble it.
Re: Have I just blown a head gasket ??
Posted: 12 Dec 2012, 08:28
by cruachan
Well, I did all the studs earlier this year so hopefully that's one less thing to worry about. Do the engine number digits tell me what year it is or is that info available elsewhere.
From your advice I'm assuming the cylinder head studs can be a problem?
Re: Have I just blown a head gasket ??
Posted: 12 Dec 2012, 09:44
by Ian Hulley
cruachan wrote: Do the engine number digits tell me what year it is or is that info available elsewhere.
From your advice I'm assuming the cylinder head studs can be a problem?
The engine number may tell the story or it may just be a case that has been rebuilt. The fact that the exhaust studs have been done is a major plus point ... What about the head studs ? Yes early studs are prone to snapping and all can rust and snap like a carrot if the correct mixture of antifreeze/water hasn't been used. Being a late van it should have the better later studs and you just may be lucky.
There's a whole raft of other jobs you'll be wanting to do while the engine's out ... clutch (inc lubeing the lever and bearing guide), replace spigot bearing (if manual), bellhousing starter motor bush, thoroughly check engine & gearbox mounts, check the cooling system components thoroughly and replace if slightly iffy, ditto exhaust components, possibly the oil pump too, if you drop the engine AND gearbox (some people prefer it that way) then regrease the CV joints, weld M8 nuts under the slave cylinder bracket change gearbox oil .. the list goes on.
Good luck.
Ian
Re: Have I just blown a head gasket ??
Posted: 12 Dec 2012, 10:10
by cruachan
Ok so if we come from the opposite direction for a moment. If I hold up my hands and say I don't really fancy doing all that work right now then can the issue of the leaky seals be lived with for the time being?
Is it going to get worse through using the van? If the coolant level is kept at the correct level and checked regularly should that be enough or are the seals going to let go big style in the wrong place and at the wrong time?
The thought of pulling the motor apart is giving me a headache.
Re: Have I just blown a head gasket ??
Posted: 12 Dec 2012, 10:18
by Ian Hulley
cruachan wrote: Is it going to get worse through using the van? If the coolant level is kept at the correct level and checked regularly should that be enough or are the seals going to let go big style in the wrong place and at the wrong time?
You can never tell, it could last 5 years it could last 5 days ... that's the trouble with bodges or ignoring known faults. IF it all goes Pete Tong it could cost you the engine in the worst case scenario ... nowt that a grand can't put right of course.