overheating engine

[janieh]

Hello,
Any advice appreciated.

Our cooling system seems to have been playing up recently. The light had been coming on and a few months ago the garage did a proper sort out of it and filled it all up and got the air out (they said). Anyway, it hardly gets driven, and yet the next time I went to use it the light came on again. Back to the garage, as I wanted it sorted before our holiday to the New Forest. They did the full service and also said they pressure tested the cooling system, no leaks and it just needed topping up a bit.

Yesterday, after nearly two hours trying to get from Brixton to the M3, with the light flashing again, the engine seemed to be getting hotter than it normally does. Then after we got some speed up the gauge went right to the top. We were worried so pulled over at that point. We checked the coolant level in the top up tank by the reg plate and it was really high - up near the top rather than between the two marks. We didn't check the main tank as we had an awning on the boot and our bikes on the rack so we just ended up letting it cool and then driving home. Didn't fancy it overheating and being stuck on the hard shoulder with a screaming toddler. Oh, the only other thing is that the interior air vents are blowing temperamentally hot and cold, even when the engine is clearly hot.

I was pretty upset at missing our camping trip yesterday, and also annoyed that we've been to the garage three times with this now and it's still not sorted.

Any ideas before I have to go back to the garage? (sorry for the long post)
Ta, Jane

[Ralf85]

Did the cooling fan kick in when the temperature went up? Does you current garage work on our vans regularly? If not the cooling system may not be full up. If your van is left a long time and there is a slight leak it could be a possible airlock in the system. It does take a lot of careful effort to fill and bleed the system completely, including making sure the heater lever is open to ensure the whole system fills up.

Also, the coolant pump might be knackered preventing the coolant moving around the pipes and engine.

[rob1927]

It might be worth removing the belt(s) from the water pump and alternater, and checking by hand if the water pump and alternater pulleys arent stiff due to worn bearings, they should turn quite freely by hand.

[ghost123uk]

You did the right thing not continuing. Engines can easily get wrecked by cooling problems and overheating.

Oh, the only other thing is that the interior air vents are blowing temperamentally hot and cold, even when the engine is clearly hot

This is the main symptom of a major air lock. There is no doubt that you now need to do two things.

Firstly make sure it is correctly filled and correctly bled. (Full details in the wiki).

Secondly you need to take it to a local garage and get a "sniff test" done.

This involves putting a probe into the header tank (the one on the left that should be full to the brim) and a little machine then tests for combustion gasses in that tank. If it finds any, it generally means a head gasket has failed or the head has cracked (not uncommon on your engine, and not the end of the world either, unlike so often is the case with the petrol WBX engine) This causes air locks to appear in a system that was previously bled.

Note though, I wonder if the garage you took it to bled it properly ? There is a bit of a technique to follow to do it properly on a T25 (see that wiki article).

Top it up, bleed it and get that sniff test done first, for your peace of mind and so you can then look for other causes. It won't cost much at all, only taking a few minutes to do (the sniff test that is).

[janieh]

Thanks for the advice. Yeah I think I need these things checked out now. Our garage has previously been pretty good. It's a VW garage and they used to look after a lot of these types of vans years ago, but not many now. I might have to take it to Volkspares again as they do more of the older vehicles, they're just not as convenient for us.

[ghost123uk]

Bleeding it yourself is quite easy you know. If you are not confident, I bet you could find someone on here to come and show you for a beer or two. There must be plenty of 80-90 members in London

Or, look at our list of T25 friendly garages in the wiki = here.

Then any self respecting garage can do a sniff test = 10 minute job.

[Ralf85]

Thanks for the advice. Yeah I think I need these things checked out now. Our garage has previously been pretty good. It's a VW garage and they used to look after a lot of these types of vans years ago, but not many now. I might have to take it to Volkspares again as they do more of the older vehicles, they're just not as convenient for us.

I've sent you a pm!

[California Dreamin]

As Ralf said...does the electric fan cut in? faulty thermo switches are pretty common this time of year (when they work for the first time after an autumn/winter where the coolant just doesn't get hot enough to trip the switch). It is often the FIRST long drive that reveals the switch fault..especially when getting stuck in traffic.

I would also change the DARLEK cap as a matter of cause...if the cap isn't allowing pressurisation the coolant will boil at a lower temperature than it should.

Martin

[janieh]

Hi Guys.

Thanks for advice. We're still not sorted unfortunately. Van went back to the same garage as they agreed to spend time on it without any extra charge. They spent quite a while on it, and when I went to collect they claim that they're sure the light is an electrics issue due to the circuit board and not an actual coolant issue. (they did some test that shorts the electrics and means the light shouldn't come on, but it did).

However, after driving it around a bit I've discovered I'm still having the issue with the blower sometimes going cold and the heat increasing a bit more than is normal. I don't think I want to take it back to them as I've got to the point where I don't feel they know what they're doing enough!

The dalek cap - is that the header tank cap? I'll get one from Brickwerks. Also, he mentioned something about a valve that may have caused the high level of coolant in the top up tank. Any ideas? is there something else I should order while I'm at it?

Do you think there might be anyone near Brixton that may be able to come and help us out? We're not really sure what we're doing! How would we find them?

Cheers
Jane

[ghost123uk]

The dalek cap - is that the header tank cap?

Yes

I'll get one from Brickwerks.

Also, he mentioned something about a valve that may have caused the high level of coolant in the top up tank. Any ideas? is there something else I should order while I'm at it?

That valve is part of the "Dalek" cap.

Do you think there might be anyone near Brixton that may be able to come and help us out? We're not really sure what we're doing! How would we find them?

Hopefully someone will be along soon with a recommendation...
Did you look in our "wiki" at the garages section, there might be one in there ?

[300CE]

Might be worth giving Olly a call at T25 Direct in Dulwich:

http://www.t25direct.com/" onclick="window.open(this.href);return false;

Or maybe the VW Engine Company in Deptford - they maybe able to advise or point you to someone:

http://www.thevwenginecompany.com/" onclick="window.open(this.href);return false;

Hope you manage to get it sorted

[janieh]

Also, he mentioned something about a valve that may have caused the high level of coolant in the top up tank. Any ideas? is there something else I should order while I'm at it?

That valve is part of the "Dalek" cap.

Do you think there might be anyone near Brixton that may be able to come and help us out? We're not really sure what we're doing! How would we find them?

Hopefully someone will be along soon with a recommendation...
Did you look in our "wiki" at the garages section, there might be one in there ?

Thanks, I've ordered the cap so once it arrives we can see if that makes a difference.

I've looked at the wiki garages and unfortunately there's hardly anything in London on there. I can always try Volkspares again. They've been ok in the past.

[janieh]

Might be worth giving Olly a call at T25 Direct in Dulwich:

http://www.t25direct.com/" onclick="window.open(this.href);return false;

Or maybe the VW Engine Company in Deptford - they maybe able to advise or point you to someone:

http://www.thevwenginecompany.com/" onclick="window.open(this.href);return false;

Hope you manage to get it sorted

Thanks for the tips. I hadn't heard of T25 direct and that's really near.
cheers

[janieh]

Might be worth giving Olly a call at T25 Direct in Dulwich:

http://www.t25direct.com/" onclick="window.open(this.href);return false;

Thanks so much for this tip. They sound brilliant. I just spoke to them, and aren't booking in the van yet as I'm waiting for my new header cap to arrive. However, I told him about the issues we've been having with the other garage, and the fact that they blame the circuit board but say it can't be replaced. Anyway, this guy has circuit boards so will easily be able to change and check if that is the problem. I'm probably going to book the van in with him next week.

Cheers
Jane.

[New Kentish Campers]

It's not a bad idea to test your new Dalek cap before you fit it.

Just blow hard though the pipe outlet and you should hear a quacking noise, like a Duck If you can blow straight through with no noise, then it's a duff cap [I happened to me on a brand new one recently ]