Bleeding the cooling system

72_bay_simon · Padawan Joined: 13 May 2006 Posts: 79 Location: Hampshire

I seem to remember reading somewhere that if you drill the vent in the thermostat to 5mm and remove the little check ball it makes bleeding the system easier and has no adverse effects on the running of the motor.

Anyone donw this? Or am I immagining things!

mark-s · Posted: Wed Jun 07, 2006 1:01 pm Post subject:

i just drilled a 3mm hole in the thermostat - bleeding is dead easy now. takes a bit longer to reach operating temperature, but no big deal.

I also read that drilling a hole is good for remote radiator systems, because of the large volume of stationary water that has to be moved when the thermostat opens. With a hole drilled, it's already moving slightly, so is leas strain on the water pump. this could be a load of rubbish of course...

72_bay_simon · Padawan Joined: 13 May 2006 Posts: 79 Location: Hampshire

Thanks for that. It seems you agree with what I read (or immagined!). I will break out the drill bits.....

Where have you mouted your radiator?

mark-s · Posted: Wed Jun 07, 2006 2:59 pm Post subject:

It's under the bus between the chassis rails

72_bay_simon · Padawan Joined: 13 May 2006 Posts: 79 Location: Hampshire

Thats exactly where im going to put mine! Do you have a scoop or anything?

Does it run cool enough?

Any pictures?

Thanks!

mark-s · Posted: Thu Jun 08, 2006 12:53 pm Post subject:

no scoop, but it's at a slight angle with a fan behind it. I haven't driven in it any distance yet, just round the streets where it stays between 80-90 degrees. I do have some pics but they're still on my camera. I'll post them up soon.

autohausdolby · Padawan Joined: 20 Jun 2006 Posts: 51 Location: Sheffield

I've never heard that before - is that the general consensus?
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mark-s · Posted: Wed Jun 21, 2006 11:11 am Post subject:

I've seen pics of vans with radiators in loads of diferent places, but underneath seems to be a popular location - plenty of people have done it in Australia, and requires no body modifications.

autohausdolby · Padawan Joined: 20 Jun 2006 Posts: 51 Location: Sheffield

Ooops! My bad - I meant drilling the thermostat Happy

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mark-s · Posted: Wed Jun 21, 2006 11:38 am Post subject:

ah right - I just read about it somewhere so I thought I'd try it! Certainly helped the bleeding procedure.

rjes · Posted: Sat Jul 29, 2006 3:04 am Post subject:

Mine runs fine and bleeds very easily with no drilled thermostat or additional preather points in the system.
Unless I can find conclusive proof that something like drilling a thermostat works (such as Tom Shiels' work on heater bypass pipe bores), I leave it alone.
How easily the system bleeds is all to do with the design of the circuit. Some I have seen are truely awful - clearly done from a 'minimun effort' perspective, rather than designed to wirk. This doesn't prevent them being widely used though. See http://www.rjes.com/html/cooling_system.html for my circuit design. I've been very pleades with it. The key things are to have a through flow header tank - preferably all of the heater circuit flow, and to take the flow for this from a system high spot.
Read the thermostat'spage too - you DONT want to use an aftermarket thermostat!
Hope this helps.....
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panel · Posted: Tue Jun 21, 2016 1:39 pm Post subject:

Anyone still drilling a hole or removing the little check ball ?
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