Club G40 Forum

Technical => Engine and Transmission => Topic started by: wierdo on January 13, 2010, 08:00:07 pm

Title: Bigger water radiator
Post by: wierdo on January 13, 2010, 08:00:07 pm
Where I live in the summer becomes very hot temperatures around 36-39C and driving the G around in high traffic at low speed makes me see temperatures about 95-100C.

So I have decided to install new bigger water radiator. The ones with the holes in the left are only 700-720x320x32.
I think there is a way to put it a little bit on one side so it can fit in front of the charger. I have measured and maybe it will fit.
Have anybody done this ? Or, give some advice ?

Thanks
Title: Re: Bigger water radiator
Post by: giorgio on January 13, 2010, 10:43:09 pm
http://www.polog40.co.uk/forum/index.php/topic,3726.0.html

Has potential.

Although it may be an idea to change the fan rather than the rad.

If your in traffic its the lack of cool air that is making your car hot, rather than your rad being to small. All the rad in the world wont cool in 100degrees.

I know you can fit 2 highflow slimline fans to a stock rad. This will allow the heat to escape from the rad.
Title: Re: Bigger water radiator
Post by: wierdo on January 13, 2010, 11:05:46 pm
The fan will be the first thing to change. The question is can I combine the new slim fan with a bigger radiator, to get a better result.
Title: Re: Bigger water radiator
Post by: Puncharado on January 13, 2010, 11:18:30 pm
Absolutely agree with giorgio. For cooling performance you want one high flow fluid and one low flow fluid. In traffic both airflow and coolant flow are low so you need more airflow with a better fan set up. You can also connect an over ride switch to the fan motor so that you start it up before the temp sensor does, which will stop it getting so hot in the first place. IThis can also be achieved if you use a twin fan set up and use an additional lower temp switch to automatically start one up sooner so the second fan will ony come on when it really needs to.

A bigger rad is only any good if high air flow is also available. Also a bigger rad will put more stress on your water pump.

An alternative is to open all the dash vents and turn your heater and blower up to max, et voila a bigger rad!!
Title: Re: Bigger water radiator
Post by: Justin14100 on January 13, 2010, 11:21:17 pm
An alternative is to open all the dash vents and turn your heater and blower up to max, et voila a bigger rad!!

Haha, a classic on your 1l fox with a head gasket going, full heat all the time!

maybe my temp sensor is faulty but mine always seems to be at 70ish, a few times i saw it  up at 90 but very rarely!
Title: Re: Bigger water radiator
Post by: PeteG40 on January 14, 2010, 11:26:38 am
would an oil cooler also help?
Title: Re: Bigger water radiator
Post by: giorgio on January 14, 2010, 12:12:19 pm
Same kind of principle as the rad. If there is no air flowing through it then it wont be as effective
Title: Re: Bigger water radiator
Post by: PeteG40 on January 14, 2010, 12:18:50 pm
yeah but at least adds another rad into the system to keep the engine cool. 
Title: Re: Bigger water radiator
Post by: Alexiskayak_7 on January 14, 2010, 12:59:27 pm
Where I live in the summer becomes very hot temperatures around 36-39C and driving the G around in high traffic at low speed makes me see temperatures about 95-100C.

So I have decided to install new bigger water radiator. The ones with the holes in the left are only 700-720x320x32.
I think there is a way to put it a little bit on one side so it can fit in front of the charger. I have measured and maybe it will fit.
Have anybody done this ? Or, give some advice ?

Thanks

Wierdo, i live in Greece, we also have high temperatures (40C+) in summer, but the water was never going more than 95C even i was stuck in trafic...
Try a colder thermostat and a colder fan swich...
When i instaled an oil cooler i never saw more than 92C...
Also try cleaning the radiator fins or replace the radiator with a new one but i don't think that you need a bigger one...
AND check if the fan kicks at 2nd speed...
Title: Re: Bigger water radiator
Post by: Varley on January 15, 2010, 12:25:09 am

An alternative is to open all the dash vents and turn your heater and blower up to max, et voila a bigger rad!!

 

Standard Procedure!
Title: Re: Bigger water radiator
Post by: lance on January 15, 2010, 02:37:03 pm
http://www.carcooling.co.uk/products/Radiator_VW_Polo_III_a_1398_cc_1990_94_10_90_09_94_1_4_D_Diesel_Manual_525_320_34mm_12VW398-64050-1280.html
Title: Re: Bigger water radiator
Post by: djtez on January 15, 2010, 08:44:15 pm
idono the sandard dimensions.. is this bigger than standard..
Title: Re: Bigger water radiator
Post by: wierdo on January 15, 2010, 10:34:10 pm
Oh, so much replies.
I have Oil cooler with thermostat which opens at 86C. This one: http://www.bar-tek-tuning.com/lshop,showdetail,21447,en,1263594405-21457,1100250806.1204545103,2240003,2,Tshowrub--1100250806.1204545103,.htm
. Everything in the water system is brand new and stock.
I have found one bigger radiator that will fit. It is from a diesel polo I think. It's this one: http://www.euro07.bg/uploaded/article_images/6280.jpg

First will change the fan with bigger one 280mm. and force it start at lower temps so water keeps around 90C. If this does not do the job will try with the bigger rad.

Thank you guys for your sharing, will keep you updated with the results.
Title: Re: Bigger water radiator
Post by: Tommo on January 25, 2010, 07:12:35 pm
I dont see why it should need a bigger radiator myself, a G40 shouldnt take much keeping cool in traffic, less than a normal polo I should imagine.

I would suggest a coolant flush, maybe even a new standard rad.
Title: Re: Bigger water radiator
Post by: scotsjohn on January 25, 2010, 07:44:36 pm
Maybe some "Water Wetter" from Demon Tweeks. There are a couple of similar products about which I can't remember off-hand,that make the most of what you've got.
Title: Re: Bigger water radiator
Post by: hayesey on January 25, 2010, 08:19:20 pm
I don't have problems with my standard rad on track days with the turbo. 
Title: Re: Bigger water radiator
Post by: poloeatonm45 on January 25, 2010, 11:05:26 pm
hayesey do you have a part number for a standard g40 rad?? im looking for a new one also do you have any idea of how much  they are?

steven
Title: Re: Bigger water radiator
Post by: Puncharado on January 25, 2010, 11:45:23 pm
Got a brand new one upstairs, number on the box is 867 121 253 AB
Title: Re: Bigger water radiator
Post by: poloeatonm45 on January 26, 2010, 06:02:37 pm
is that a propper g40 one? or jus a standard mk3 rad?

steve
Title: Re: Bigger water radiator
Post by: wierdo on January 26, 2010, 07:18:48 pm
Mine is brand new, as all in the water system (pipes, pump, etc.) and stock.
But here in summer is very very hot, temperatures over 39-40 Celsius.

Title: Re: Bigger water radiator
Post by: Puncharado on January 26, 2010, 08:02:47 pm
is that a propper g40 one? or jus a standard mk3 rad?

G40 rad. Got a mate who works in VAG parts dept ;D
Title: Re: Bigger water radiator
Post by: poloeatonm45 on January 26, 2010, 08:46:20 pm
any idea on a prive for a g40 rad in the uk????

steven
Title: Re: Bigger water radiator
Post by: Puncharado on January 26, 2010, 08:51:07 pm
any idea on a prive for a g40 rad in the uk????

I haven't, mine's been in waiting for probably three years or more!
Title: Re: Bigger water radiator
Post by: poloeatonm45 on February 25, 2010, 03:24:41 pm
just been to vw and they want £126 for a g40 rad that is bloody expensive i nearly fell over

steve
Title: Re: Bigger water radiator
Post by: Puncharado on February 25, 2010, 06:58:28 pm
I've since got my reciepts file out, turns out I bought mine a year ago. Mate's rate was a fair bit cheaper than that quote!  ;)