Club 80-90 Forums

Hello all
Really hoping someone can shed some light on this. Took the van, for the first time to a garage to sort out a coolant leak (was way too busy to do it myself, though i wish i had now!) Driving it home (only 2 miles at most) the water temp warning light came on, got home and realised the garage hadn't put any replacement coolant in and pulled lots of air through
Filled and bleed the system but found the water wasn't circulating _ the bottom main coolant hose was scorching hot and the top hose was stone cold.
So i bled the system again and found the rad to be near on empty!?! Filled and bled and the tempreture still doesn't even out with the main coolant pipes. Bottom ones really hot and the top stay cold.
Next thing thought 'stuck thermo'. So change that, bleed system and pipes still the same - bottom scorching, top cold. Next think could it be the pump? So spend two days doing that (took it all out the first time, put it all back together and as i forgot to change the pump O ring it leaked everywhere, so all out again ARGH! but at least all the bolts where freed up!!) Bleed system and try again. Still in same predicament - bottom pipe scorching, top pipe cold. Rad doesn't seem to get very warm and i have had to top it up twice directly into it. I've also changed the rad thermo switch as i can't ever remember the fan coming on, but it's always ran at a good temp before. Could it be mases of air? Temp on dash only gets to about half way now (but used to sit just over the top of the white mark, before this all began) Plus temp light does not flash everytime if it heats up anymore that that. Really starting to get worn down by it. Any help would be massively appreciated

Did you follow the advice on bleeding in the wiki? https://club8090.co.uk/wiki/Co ... ing_system

Yes, i've read the wiki and watched so many videos on correct procedure but have found the if the vans facing down hill i can get better results at the rad end. But to be fair i've tried bleeding the system both ways about 10 times now! I now its a bit of a pain in the backside, but i would have thought it would be done by now!! Its the coolant pipe tempreture not evening out thats got me worried.

I know there are many opinions on how to do this but this is the way I've done it many times on 4 different vans.

Never bothered with having the front up but do it if you want.

Get someone to rev the engine up to around 2500 rpm and get as much coolant/water into the reservoir as you can, don't let the revs drop or it will p*ss out.

Have the radiator bleed screw open and the heater on hot.

When water comes out the rad and you've got as much in as possible fill the expansion tank to the mark and release any air from the engine bay bleed screw.

Take it for a run and get up to temp.

Come back and do it again.

I've used this method following an engine swap, a radiator swap and a full front to back water pipe swap inc heater hoses and never failed to get all the air out after no more than 2 repetitions.

So what the op is saying is the pipe from the pump to the rad is hot and the one coming back isn't ......
Then surely the rad is doing it job ?

No mention of what engine, so I'll assume it's not a diesel...... And that it's a late water system .....
( because you don't change the thermostat and the pump at the same time )

Just in the middle of that and' wahay' the rad is finally heating up evenly so i assume the pipes will too! I'll take it for a wee spin now and run through the procedure again

Mocki wrote:So what the op is saying is the pipe from the pump to the rad is hot and the one coming back isn't ......
Then surely the rad is doing it job ?

Soz must have been putting my reply on same time. That does make sense! Lol. But does the one pipe get so hot you wouldn't want to hold it for long at all?

Well, just got home - Still overheating on the gauge Though the red light won't flash and the engine itself doesn't seem hot. Could i have got the pipes to the thermostat the wrong way round? Would anyone out there have a pic of them? (tried google but nothing in detail that i can work out )

Hi Plan38.

Just to note - my van heats up to just over half, and stays there. The needle basically covers just under half of the red LED normally.
I have a new rad, thermostat and housing, new coolant lines ( most of them ) so I assume that the running temp is right.

My fan kicks in about 3/4 of the way up the temp gauge, although I have to be sat in traffic for an extended period to get to that stage.
( It doesn't get warm enough while driving. )

This seems normal to me, and you do say in your comment that the temperature that your gauge reads is half way, with no flashing LED...

What exactly do you mean when you say it is still overheating? ( If it is just because the gauge gets a tad over half way, then I would say that is normal. )

Nah wish it would stay at half way! Went to get the kids from school (about a three mile trip) and the temp needle went over the 3/4 mark. Got back and the bottom pipes boiling hot top pipes stone cold and the rad stone cold with no fan kicking in

Thermstat opening?

Is it a petrol?
Do you have a late van with plastic thermstat housing?
Does your heater in the front get nice and hot?

Sorry should have included all that in the first post! Its an early 1.9dg. Replaced the thermostat and the heaters in the front work really well. I've got the pipes set up to the thermostat as follows: bottom pipe to to top of the thermostat, top pipe to the bottom of the thermostat - does that sound right??

plan38 wrote:Nah wish it would stay at half way! Went to get the kids from school (about a three mile trip) and the temp needle went over the 3/4 mark. Got back and the bottom pipes boiling hot top pipes stone cold and the rad stone cold with no fan kicking in

Sounds like the pump might not be moving any water around to me...? Can you see water movement in the header tank when you rev it from the engine bay? Might need the blue darlek cap off to see the level rise and drop with revs.

Sympathies are with you, think we've all spent many hours with the water pipes :'(

Changing an early water pump is perhaps the worst!
Good luck

plan38 wrote:Sorry should have included all that in the first post! Its an early 1.9dg. Replaced the thermostat and the heaters in the front work really well. I've got the pipes set up to the thermostat as follows: bottom pipe to to top of the thermostat, top pipe to the bottom of the thermostat - does that sound right??

An early van will not have the plastic thermostat housing that I have, so I can't comment on that bit. Someone here will though.
I would try and make sure your fan is working correctly though.

It should kick in about 3/4 of the way up temp gauge. If not - as it sounds like yours didn't - it could be that.
( Although mine never gets hot enough in this weather to need the fan. )

Have you checked the WIKI?
There should be a bit in there ref early cooling systems. Even if it isn't fault specific, there may be pics and diagrams of what you need.

Ah i've changed the pump just in case (luckily i have a very splendid donar van) and the thermo switch for rad. Still no joy