Overheating problems.................T25 DG series 1987

Post by **Jutstar** » 11 Oct 2008, 20:19

I have read loads of threads now regarding overheating. I ve got the usual coolant coming out of the expansion tank, and then causing overheating.

Firstly thought it was a faulty thermostat, so replaced it, still the same problem but noticed that all the waterpipes around the engine were hot but the pipe the other side of the thermostat was cold, and also the rad was stone cold.

Taken it to a garage and they changed the expansion tank, cap and sensor and reckon that the overheating and loss of coolant stopped however there was alot of pressure coming into the system. (expansion blew up like a balloon)

Its not misfiring and runs sweet, the garage reckon that its eiether a cracked head or piston seal and are reccommending a new recon unit. No sniff test of compression test carried out as yet.

Also mentioned that the water pump is leaking.

Now £160 lighter i am set with looking at a new engine, just wondered if people felt that this diagnosis was accurate and whether i should get a second opinion.

Post by **Fritz** » 12 Oct 2008, 07:28

Make sure the small bore pipe which runs around the inside of the engine conpartment and all the pipes linked to the engine are clear of any restrictions.

Regards

Fritz,,,,,,,,

Post by **dugcati** » 12 Oct 2008, 10:28

check the rad is getting warm (all of the rad not just the bottom0 - sounds like airlocking in the water system

Post by **jason k** » 12 Oct 2008, 21:22

dont mess about , get it sniffed this will give a definitive answer. if all is well with the sniff test change your thermostat for a genuine vw one. gsf ones are sh1te.
then rebleed.

but get it sniffed, its normally free too.

Post by **stuart vw540** » 13 Oct 2008, 12:50

I had a similar problem, I was fine whilst moving, but when I stopped at junction's or services all the water would get thrown out into the overflow.
The AA found that the Blue pressure cap was not holding any pressure, so Just Kampers came to my rescue at Bug Jam 2008, as the van kept overheating all the way there, I did actually drive in through the gates and around to club camping, with the AA van following me.
After that all seemed reasonable, except for airlocks, which meant that the pressure cap would allow water to go into the overflow tank when warm, but would not suck the water back in when cold, tried blleding till I was blue in the face, even took to topping up the pressure vessel every time I stopped for more that 15 - 20 min's, also letting the air out of the bleed screw on top of the thermostat housing, this did help as a temperary fix, to keep me going, even got from Redditch to Skegness and back, but alas only temperary as now my distribution pipe has burst and I am having trouble finding one, someone on here has given me a lead and I am currently checking that out.
Anyway to cut a novel short, when you have had sniff test's and the like done to rule out anything from that side, find someone with a vacuum bleed machine, usually garages, because that should solve any air lock's, as trying to bleed with the bleed screws and following the guidlines in the Haynes manual just doesn't work, I have tried everything to the point that now the bleed screw on my radiator no longer open's, as I would never get it back in again, so in my mind a vacuumn bleed system is the way to go.
I used to have Toyota MR2, so similar engine and cooling system setup, and had the same problem woth that, until it had the vacuum pump treatment, then good as gold.
Oh well, hopefully have my bus back on the road soon, good luck.