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Discussion Starter #1
Good afternoon..

Did the usual Oil Change on my Van today, figured while I had the under tray off, I would give the coolant a flush and change as I haven't done this since buying the van.

I dropped all the old coolant out and flushed through the radiator with a hose.
I refilled the system with G12 Coolant and then ran the engine with the cap open to expel any air bubbles.I hear there is a bleed screw on these vans but I had a good look and no idea where to find it! (any detailed pointers?)

Now the Van gets up to temperature on the dash but the Coolant light constantly flashes, even though there is coolant up to the max line on in the reservoir. As well, the fans blow hot when I am travelling at about 50mph but as soon as I idle, they go cold again. I can feel the top radiator hose is hot, but the bottom one is cold.

Is there any suggestions on how to solve this or what im doing wrong? And also, is the van alright to drive short distances? Is there a chance of overheating?

Thanks very much and hope to hear some good news!

Cheers,
Lee
 

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Almost sounds like the water level is low, did you recheck after a road test?

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There’s a bleed actually on one of the hoses that goes through the bulkhead, it’s close to the bulkhead
 

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Discussion Starter #4
There’s a bleed actually on one of the hoses that goes through the bulkhead, it’s close to the bulkhead
Thank you for the pointer here, I’ll have a look tomorrow and see if I can bleed the system this way!

Thanks!
 

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Almost sounds like the water level is low, did you recheck after a road test?

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Yeah it does seem that way doesn’t it.. I put 7L I’d coolant into the system and it’s up to the Max line. It did drop slightly after a 10 minute drive (where it got up to temperature) but I refilled and still no heat through the fans at idle and the lower rad hose is still cold.

I have heard that squeezing the hoses will hopefully push the air out as it does seem like there is an airlock somewhere. But I will have another detailed look tomorrow and see what I can find out.

Thank you for your help!
 

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Sometimes air settles over night so check for level today. Think the bleed point is in one of the heater hose to the matrix near the coolant bottle if not, just be careful not to snap it as they are normally plastic

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Near the bulkhead is a hose with a plastic bleed nipple in it. (Be aware....OLD plastic....has been know to break when opening!)
You could always split the joint, but again..OLD hoses...may not seal again. o_O
Did you have the heater set to fully open when you did the drain, otherwise some fluid will drain out, leave some in, but cause an airlock when re-filling.

I NEVER fill mine to Max....but 10mm below.
As it expands, it just blows the excess out, and you "think" you have "lost some somewhere".
Max, should only read when at full temp....hehe..it's why it's called an "expansion tank".

Gentle "hint"...always state what engine when asking questions....luckily it was in your profile, but I had to look it up. (Sooo many T5 people posting in this section now!)
 

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Discussion Starter #8
Near the bulkhead is a hose with a plastic bleed nipple in it. (Be aware....OLD plastic....has been know to break when opening!)
You could always split the joint, but again..OLD hoses...may not seal again. o_O
Did you have the heater set to fully open when you did the drain, otherwise some fluid will drain out, leave some in, but cause an airlock when re-filling.

I NEVER fill mine to Max....but 10mm below.
As it expands, it just blows the excess out, and you "think" you have "lost some somewhere".
Max, should only read when at full temp....hehe..it's why it's called an "expansion tank".

Gentle "hint"...always state what engine when asking questions....luckily it was in your profile, but I had to look it up. (Sooo many T5 people posting in this section now!)
Hi and thanks so much for all your help there!

I did in fact locate the bleed screw - I spotted it as soon as I opened the bonnet today.. I can't believe I missed it yesterday! Mine seemed to be in good condition - I can open and close it with finger tightness alone so that's a good sign!

Absolutely. I think in my frustration with it all yesterday I didn't even explain what engine I had!

Thanks for all your tips with the expansion tank and hoses. Much appreciated! I've done coolant changes of Volvo's and Jeeps in the past and never had a problem like this so wondered what was going wrong!

I am pretty certain I did have the heater open when I did the drain. But in any case, opening the bleed screw to let air escape will rid the system of airlocks anyway. Is that correct? As well, I left the expansion cap off whilst the van heated up to burp the system, this would also have expelled all the air?

Thanks again for all your help, much appreciated!
 

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Discussion Starter #9
So to update on today..

There was no warning light on the dash which is a good sign!
The vans coolant had settled a bit since last night. It was well below the MIN line. So I topped it up between the min and the Max and got the van up to Temperature. I found the bleed screw leading to the Matrix and when I opened this a bit of air came out and then coolant seeped out.

On the Radiator - the bottom hose was still cold and the top really warm. So something must be wrong? I squeezed all hoses and especially the bottom one - this just made coolant erupt out of the system.. So I'm guessing I'm just pushing coolant around the system and its overflowing? It doesn't feel like there is any air in there..

I took the van for roughly a 6 mile drive and the fans blew hot when I was cruising at 50mph but cooler when I was idling. When I got home, I released a little more air through the bleed nipple until coolant came out. Now my fans were blowing slightly warmer at idle and the bottom hose was slightly warmer as well. My fans were never amazing on this van to begin with and its the height or summer up here so I figure this can be a problem I can try again in a few months!

I am assuming its not the water pump as coolant is clearly circulating the system as I can see it coming back into the expansion tank bottle from the smaller hose?
Could it possibly be a problem with the Thermostat? ie. The thermostat is not opening to pull coolant into the system? Or not?


Can't believe I missed this bleed nipple yesterday.. It's at the back of the engine bay, I wasn't looking there unfortunately!

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Should this be getting hot when the van is up to temperature? It remains cold and I can touch it?

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Basically - is the van alright to drive as it is? There's plenty of coolant in the system and no warning lights.
I do plan on doing another coolant flush again and this time will probably replace the thermostat as I may as well while I'm there.


Thanks for all of your help so far!
 

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Does sound like a poor thermostat, the bottom hose should be cool until the thermostat opens when it's up to temp. Worth putting a new thermostat in but use a good quality one or it will end up the same.
The bit on top the engine is the intercooler that cools the air going into the engine so should be cool too

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Does sound like a poor thermostat, the bottom hose should be cool until the thermostat opens when it's up to temp. Worth putting a new thermostat in but use a good quality one or it will end up the same.
The bit on top the engine is the intercooler that cools the air going into the engine so should be cool too

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Thanks gtijames for your help with this and advice on the bleed screw. Luckily mine seems to be in good condition so no damage or snapping when opening or closing it.

In the end I dropped all the coolant out after a few weeks and did another flush and change. This time I changed some hoses, the thermostat housing and thermostat.. Figured I may as well considering it was up on ramps anyway and it saves me doing it at a later date.. The job went better than before and after getting all the old coolant out and refilling, the van got up to temperature and now the fans blow red hot constantly.. It must have been a small issue with the old thermostat, it looked like the original one so it's definitely proved its mileage. All good now and the van is better than ever!

Thanks again for all your help, really appreciated!
 
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