Radiator on its last legs? (Aux rad?)

[dan_b]

Hi guys
Fiddling around (on my day off as well) with the S2 today and having had the car running for an hour or so, I opened the bonnet to check a few things.

I noticed that the small radiator that runs along the front horizonal length of the nose of the car immediately behind the front grill is weeping ever-so-slowly in 2 places. There appear to be quite a few vanes missing, obviously some insects have had their last laugh on this radiator...

Is this the much-maligned Aux radiator? There is another radiator further back and to the side of the engine with the big sucking fan (and the aircon unit in front of it) which I assume is the main rad.

How much to replace, or should I just take it out as quite a few people here seem to have done with no side-effects? Mine's a 3B if that makes any difference.

Is this an easy job for a goon like myself? What happens to the two hoses that take coolant in and out of the rad? Do these need to be replaced, or can I just bodge them and plug them up with something that's not going to leak or pop out?

I'm sure this has been asked, and answered before!

Getting seriously cross with my S2 at the moment, it's just a constant stream of faults

[S2central.net]

Thats the aux rad... Modern mentality is 'get the ****** out'

Bung up the remaining pipe holes with a 25mm errrrrrrrr bung !



Paul

[gavs20v]

yep this is the aux rad, theres another recent thread about by-passing it and using oil drain plugs as bungs for the two pipes. New rads are quite expensive, failing that might be worth getting it recored. Or use a rad from a 10v n/a 5-pot that doesnt have the etra pipe at the top for the aux rad feed and use the matching top hose from the 10v. Be much neater way of doing it. I did this on my old 2.3 20v cq and it never missed a beat water temp was always spot on.
Nice one
Gav

[dan_b]

Glad to confirm it's the Aux, and that it's current contemporary thinking to get shot of it sharpish! Is it an easy job? Can it be done without removing the front bumper etc, or should I be going to someone who knows what they're doing to do this?

[Jamo]

Even i was convinced to ditch it, think the £160 pounds for a brand spanking new one finally put the nail in it's coffin.

I replaced the tee pipe with a completely new pipe, (Ben supplied part number) instead of bunging it up and then used plumbers 22 mm copper bung to block the upper outlet.

[Jamo]

Sorry post got duplicated, don't users have the option to deleted their own posts?

[S2central.net]

Glad to confirm it's the Aux, and that it's current contemporary thinking to get shot of it sharpish! Is it an easy job? Can it be done without removing the front bumper etc, or should I be going to someone who knows what they're doing to do this?

Its easy enough - except knuckle ripping access to lower auxrad nuts. Bumper stays on...

Its a 15 minute job if nothing is rusted up along the way. Of course when I did it I had to drill out one of the upper (Torx) mount bolts which a previous nob had butchered.

Checkout S2central.net - theres a full how-to in the Technical chapter - under cooling system somewhere.


Paul

[dan_b]

Great, thanks again, I think this goes to the top of my "to do" list on my next free weekend!

[GeorgeS2UK]

Removed mine on Saturday, fairly easy job. I removed the front bumper to make life less complicated, only took 10 mins to remove the bumper and made the whole job that much easier, only tricky but was working out the best way to separate the bumper from the bottom tray under the engine as i actualy left this in place. Rad removal done 2x 25mm plugs from Forge motorsport 2 x jubilee, bled the main rad, job done.
Engine seems to run cooler and saved a mint on not having to buy a replacement aux rad.

[Graham]

I had a quote for £60 to re-core the aux rad

[dan_b]

Will I still get adequate cooling on my 3B given that I've got Air-con as well? I'm sure the air-con paraphernalia in front of the main rad can't help the airflow, although I suppose once the aux-rad is out the airflow to the engine should improve anyway? I think I'll try just by-passing it first and seeing how I get on with temperatures, then remove it later if it stays ok.

[Fat Audi 80]

I must be the only one on here who paid someone to fit a new one!!!

I sleep at night with the satisfaction that my S2 is just as Audi intended.

[jameswkr]

There are lots of old threads on this topic and a lot of us have run without the aux rad all through the hot summer of '03 with no problems at all. Blanking the pipes is much more effective than joining them together - all you are doing is bypassing the main rad without cooling the coolant.

[APNess]

Mine runs at 3 notches below 90 without aux rad, 2 nothces below if have been giving it some. In traffic the fan cuts in at 90 and temps don't really go above that, though the air con rad got pulled out too, so that helps with air flow.

We did Chris M's aux rad at weekend - piece of cake to take off, longest time was spent cutting through a section of anti roll bar (Doug's old one) to use as bungs. Perfect fit!

[dan_b]

Ok, you've convinced me. I'll bung it first to stop any further leaks and see how it runs, then when I get a bit more time will whip the whole thing out once and for all.