help! Engine HOT radiator COLD

[ermie571]

Ok folks, this could be a long one...

engine = 1990 2.1 w/c running on carb and LPG
Van = 1984 1.9 w/c

Hi chaps and chapesses,

We have recently spent alot of time replacing parts in my cooling system.

1. Thermostat housing and thermostat. As the van was displaying all the symptons of running without a termostat, temp guage rising on hills, and dropping to nowt rolling down the other side, we thought we had better put one in. But the housing had one bolt that was Sh*****ed, so when a second hand housing came along, we snatched it up! But when we took the old one off, there is a thermostat in there..... Anyway, replacement part and thermostat inserted.

2. New metal pipe that runs from the pump to thermostat housing, as old one looked in poor condition, and the pipe came with the thermostat.

3. Replaced the pump, as it seemed the sensible thing to do.


Put water in it, and started her up. Could see the water coming in the expansion tank, so believe the pump to be working.

Replaced a dodgy HT lead this morning, so seemed the ideal time to spend a bit of time making sure its bled properly.

So, expansion tank full to brim. Top up tank behind flap at max. Engine fired up and ran beautifully. BUT>>>>

THE RADIATOR IS STONE COLD. There is nothing coming through. Tried releasing the 13mm rad screw to see if there was an air lock, and water came out.

So turned it off damn quick!

What do I do now? This has only started since changing the parts above. Could the thermostat be faulty?

I must admit in changing the parts, we must have lost an awful lot of water, and I don't think I have put enough water in yet to replace the water. But its all full.So worried about an air lock.

I am letting it cool at the moment, and will then go an make sure that the expansion tank is still full, and if so, wether the levels in the top up have changed.

oh well, back to the drawing board.

All advice, as usual, greatly appreciated!

Em
x

ps - I will do my best to answer any questions

[jason k]

vw stat??

gsf ones are sh ite and cause symptoms like you describe

[Laurie]

Don't forget that the thermostat has to get to 87 degrees before it opens.
It's also wise to check the numbers on replacement stats.

If the radiator is going cold when the engine is under pressure, you may have a compression problem. Best thing is to look at Ebay and find one of the cheap chemical rad check tools under Head tools.

[syncrosimon]

Are you sure she is hot enough, I drove 9 miles the other day and the radiator did not get warm.

Make sure the heating is off, or she will not heat up.

[AngeloEvs]

Sounds as though you need to beed it again. as Mocki and Baxter say, once you have done it, do it again! Mocki and Baxter have different ways of bleeding the system and both are described in detail on this forum and on the Brickyard. I drilled a small hole in my stat. You shouldn't have to do it but I find it makes bleeding the system easier as a small volume of coolant is pumped into the rad without having to wait for the stat to open. Best of luck and no doubt you will get lots of good advice on this one.

[ermie571]

Flippin 'eck - that was quick

ok - genuine stat. don't know.....will go and have a look

Not hot enough....needle just rising beyond the led....so would have thought so, but not definite.

Don't think I have compression problems....she has been running fine - just replaced parts as some pipes were worn and leaking, and other parts seemed sensible to replace at the same time.

Thanks
Em
x

[ermie571]

ok - back down we go....

I just got worried as it seemed to be getting too hot. Will see what happens and report back.


Bleeding I am good at, but surprised at how warm the guage was with the rad cold.


Back in a bit.

Em
x

[ermie571]

ok - just spent some more time bleeding the van

Radiator is getting warm - maybe I wasn't giving it enough opportunity.

letting it "rest" now. And its flipping cold!

Thanks to those who replied.....this forum really does give you the confidence to give it a go!!

Em
x

[Pepperami]

I found reversing up some ramps made bleeding the system really easy. I think normal running the temp needle should just be past the LED.

[ermie571]

Pepp,
thanks for your assistance! But I think its nearly done! Maintaining temp just to the right of the LED - not quite coming off it, and rad getting warm.

Gotta have another couple of goes before I will be convinced that it is "bled", but think we are nearly there!

I don't have ramps.....but steep hills aren't a problem round here!!

Take care


Thanks to all that offered advice

Em
x

[dickspanner]

Ermie,

Although I do not confess to be any form of expert on VWs the guys who sold me my first crewcab are, the have been rebuilding T25s for years, and the tip they gave me when bleeding the rad and cooling system is to jack the front end up as high as you can before you bleed the rad. If no jacks then park on big hill as the routes taken by pipes from front to back allow very easy locks in them if not bled properly.

Hope this helps but other may say different.

Good luck

Dickpsanner

[sezicoolcat]

I found reversing up some ramps made bleeding the system really easy. I think normal running the temp needle should just be past the LED.

Crikey. Mine is always just over half way. Me thinks my cooling system needs looking at - FAST

SArah

[Nicola&Tony]

Crikey. Mine is always just over half way.

Sounds about right to me. That's where ours sits at once it's been running for a while and is up to temperature.

Tony

[Hacksawbob]

temp gauges change from vehicle to vehicle dependant on the state of the wiring earths etc so look at consistency one the one vehicle rather than comparing one with another. reve the engine 2000 rpm? put somehting heavy on the accel pedal for a while (10 mins) for an idling van to warm up.