Cooling system over pressurised?

[Brooksie]

1.9 petrol water-cooled 1988 DG engine flat 4. New Forest, Hampshire

Back in December one of my vans metal pipes corroded through and I lost a lot of water - I couldn't see the leak until the engine was turning over. I was AA'ed home, stripped the pipe out and repaired it, as a new one was £70 plus. Still I lost water whenever the engine was hot. When I parked up I could hear steam escaping from somewhere. A friend found a split in the header tank, which I replaced, but sadly still the same problem - once the engine got really warm- say 20 miles of motorway driving at 65-70mph - she'd pop a pipe off or blow the bottle top off.
To check there was no blockage, I emptied all the water and refilled (as haynes), checking the rad and fan.
I've done a compression test and found the 3rd cylinder is lower, the others are 9.6bar, the 3rd is 8.2bar.

I feel this is heading in the direction of a head gasket, but I have contacted several garages who are reluctant to change one- mainly because they are a problem to seal even when reskimmed. Most point to a recon engine, but the body and interior is also tired, needing probably £2500 to get her spick and span. She is much loved, and as I took all of the plates, cups and childrens games out, it was like laying out a dead friend!

I just wanted your opinions on head gaskets, have you had / done one with success or is it the death of my van?

[kevtherev]

your header cap is faulty get a genuine VW one or one from Brickwerks

explanation...
As pressure builds in your cooling system it expands into the top up tank (behind the flap)
the cap has a valve that allows this

yours is broke

[Brooksie]

Cheers Kev for coming back so soon.
Thought of that- have a brand new VW tank and cap- have tried a few caps ensuring I have the darlek one with VW code and it 'duck' sqarks.
Cap and tank working well, but why does it overheat?
Had a chat with Brickwerks to make sure I had the VW tank rather than the cheap ones other places sell.

[kevtherev]

OK so it ain't that as you didn't mention the cap I assumed you hadn't changed it

These engines have no "head gasket" like inline engines.
At the top of the cylinder liner is a rubber 'O' ring as well as the bottom.

there's a steel ring at the top of the liner which sits between the head and the liner.
So the steel ring and the 'O' ring would have to fail to pressurise the system.
The only other ways are the bottom 'O' ring failing (doubtfull)
So a cracked head (common) is possibly the culprit

[kevtherev]

Getting the head off is the biggest job, the rest is easy.
It's big because of the danger of snapping the head stud.
if you use heat then this danger is significantly lessened.

Reconditioned used engines are about £900 fitted from Elite

[M Jonesy]

Hi

I'm struggling, I have recently put a second hand engine in my 1.9 watercooled pickup and am trying to get the water system right. The top-up tank keeps filling up when I run the engine. I have elevated it and bled it from the radiator but having no luck. Do you have any ideas??

thanks

Mark

[clartsonly]

it need bleeding more or the cap is knackered

[ghost123uk]

Hi

I'm struggling, I have recently put a second hand engine in my 1.9 watercooled pickup and am trying to get the water system right. The top-up tank keeps filling up when I run the engine. I have elevated it and bled it from the radiator but having no luck. Do you have any ideas??

thanks

Mark

Mark, have you been through this procedure here =
https://club8090.co.uk/wiki/Co ... ing_system" onclick="window.open(this.href);return false;

Oh and WELCOME by the way

[Ian Hulley]

Don't buy the £3 cap from GSF they don't work. Buy from either Brickwerks or if you've one near you a VW van center

Ian

[Mr Bean]

Don't buy the £3 cap from GSF they don't work. Buy from either Brickwerks or if you've one near you a VW van center

Ian

Well I bought the GSF one a couple of years ago and it works perfectly. In fact it solved the problem that a load of new plumbing parts and a couple of recon heads failed to do. Thats why I got the van so cheap. Maybe I was lucky. Anyway why hasn't anyone memntioned the thermostat or did I miss something?
cheers
Wolfie

[Ian Hulley]

Don't buy the £3 cap from GSF they don't work. Buy from either Brickwerks or if you've one near you a VW van center

Ian

Well I bought the GSF one a couple of years ago and it works perfectly.

So did the one I bought 5 years ago ..... the latest ones don't. Steve 'Gas' Shaw bought 20 and not one worked, neither did the replacement I bought for my failed one.

You don't have to believe me but I have no reason to lie.

Ian

[Damien]

If its been to a local garage has it had a sniffer test to see if theres combustion gases in the coolant? Its usually one of the first checks most places do if compression is down, that'll tell you where to look next.

[Mr Bean]

If its been to a local garage has it had a sniffer test to see if theres combustion gases in the coolant? Its usually one of the first checks most places do if compression is down, that'll tell you where to look next.

Since you mention it you can rig up a pressure test for the whole system by introducing a small "T" and pressure guage in a suitable position and pumping it up with a bike pump. A bit like the manometer test for domestic gas leaks etc. Looking for leaks of course but not analysing the source of the leak. I suppose those lacking boxes of junk etc. could get by with a valve stem from an inner tube and after a small delay, a pressure check with a tyre pressure guage. To check the botttle and Darlek in isolation you can remove the hoses, Jubilee clip pieces of car inner tube over the outlets - one with the valve in - and just pump up the bottle if the bulging rubber deflates you know the PRV is leaking. Thats how I found the original leak.
Cheers
Wolfie