Coolant cold in return hose from Radiator???

[Diamond Hell]

That sounds 99% like an air lock.

Who are these experts?

Have you bled the radiator, using the bleed screw on top of it?

As it's a waterboxer you will need to turn the heater on, raise the front of the van by about 6" (don't quote me on that figure), let the engine come up to temp, so the stat opens, set the revs around 2k and then let the air out of the top of the rad at the front. Then you'll need to wait a while and do it over again.

Good luck.

If we knew where you are there might be someone near you who could help you out, best fill your details in as it'll make things rather easier.

[kevtherev]

my mate over t'road fitted a recon and the same symptoms happened
we did the air bleed thing 3 times before it truly cleared.
do it like the man sez

[TD]

Is the rad really new?, not just an old piece of crap?
These block easily, especially if some twerp has put rad weld in.
Do you mean VEGE?, mine is ok after 70K, so trust them(diesel)
get the bleed nut off rad and run it til hot water comes out, poke wire down it , hot water must come out.
If there is water 'coursing' through expansion tank, and level goes down, then worry!, other wise , keep bleeding

[ozzy]

I ve been bleeding mine loads due to another problem and i find if you jack the front up run the engine (i put a brick on the pedal) bleed it leave for 5 min do it again...again...again. Then take it for a spin for 10 min then bleed again then another spin then bleed again then another spin then the next day bleed again then another spin spin spin spin put petrol in then spin again you should have all the air out takes me about 1-2 hour to do it.
The symptoms you give sounds like air

[ozzy]

Keep the res full of coolant while you are bleeding thats not the one behind the number plate the other one, then when all the air is out top up and put cap on go for a spin then check rad again for any air keep engine running at a fast idle and open the bleed nut oh and make sure your heaters on hot setting.

[R0B]

that will be your problem.its deffo the front you need to raise

I thought though the back of van was meant to be raised? Not the front

[kevtherev]

bleed it leave for 5 min do it again...again...again. Then take it for a spin for 10 min then bleed again then another spin then bleed again then another spin then the next day bleed

bleedin 'ell

[Mocki]

Bleeding the cooling system on a T25Here's the proper way.......
Assuming you have an empty system, open the header tank, and fill up, put you hand over the top of the tank, and squeeze the rad pipes, moving the water around and letting the air out, keep doing this until no more water will go in, then.......
Put the van up your car ramps, or jack the front up at least 12"(or park on a hill!!)You cannot bleed a petrol T25 any other way, the shape of the cooling pipes makes it a scientific impossibility!
Put the heater on HOT, and undo the filler cap on the expansion tank, Run the van upto temp, so the thermo stat opens,
then increase the revs to 2000 rpm, then top up the expansion tank, and undo the bleed screw in the radiator, and then the one in the engine bay(if it will, do NOT force it) Keep topping the expansion tank up, ignore the top up bottle(behind the number plate) and keep topping up until only water comes out of the radiator bleed screw, should take about 20 mins, then put the top on the expansion tank, close the rad bleed screw, but leave the engine bay bleed screw open(if you opened it) then reduce the revs to tickover, leave for about 2 mins then switch the engine off, go have a coffee for about 20 ins, then come back, start it up, increase revs to 2000 rpm, open bleed valve in rad, and if you have a caravelle with rear heater, open the bleed valve in the top of that too(by the in/out pipes)take top off expansion tank and repeat bleeding until no air, only water comes out of the rad bleed screw, when you think it is all done, then put the top on the expansion tank, close the rad bleed screw, the engine bay bleed screw open(if you opened it) then reduce the revs to tickover, leave for about 2 mins then switch the engine off. Job done......

it takes about 15mins longer than you think it should, and you always need to do it one more time than you think you needed to....in short, when you think you have finished, go have a coffee, come back and do it again.

[sixsprings]

bluddy hell, what a pavlova

never had this trouble with my Aircooled

got it all to come now, i guess, but in't it nice to have proper heating

[Mocki]

tim, diesels arent so awkward to bleed, the engine isnt flat, and the pipes are less likely to airlock...that above is for petrol (wbx) bleeding

[sixsprings]

oh, ok thanks mocki.
when the temp gauge starts showing hot, then i'll ask the procedure.
if you tell me now, i'll only forget it.

[Diamond Hell]

Pah, diesels? Warm it up, crack off the bleed screw in a convenient layby, repeat, job done.