RS2 owner needs advise from the experts

[S2central.net]

There's a whole episode in http://S2central.net about the radiator fan and how to test the after-run system - its pretty straightforward.

The after-run relay is in the auxiliary relay panel.

Testing the functionality is easy with a large bladed screwdriver to short the after-run temp switch. It will only run when the engine is off. The after-run relay has a 15min timer to shut off the pump should the switch fail closed. Actually this little trick is how MarkH gets his car to ALWAYS trigger after-run pump when he shuts his engine off. Neato...

You can also hear the pump be briefly tested when the turn the ignition on.

Welcome by the way !


Paul

[Stick Insect]

Somewhere on the forum is a post about the wiring connecter for the Coupe Quattro 20V fan burning out. I don't feel it is the S2 is the same as this but I just thought I'd mention it. Was it in the section about Aux radiators?

David

[martinjs]

Actually this little trick is how MarkH gets his car to ALWAYS trigger after-run pump when he shuts his engine off. Neato...


Paul

tell me more mark/paul, how have you done that?
just what i need.

martin

[s2avant]

I wouldn't mind something like this as well. For piece of mind.

Is it as simple as shorting the switch out so the connection is always live and then letting the timer in the relay turn it off?

Ben

[Mark Halligan]

I wouldn't mind something like this as well. For piece of mind.Is it as simple as shorting the switch out so the connection is always live and then letting the timer in the relay turn it off? Ben

Ben,

thats exactly what it is, I just shorted the switch connections with a blade type fuse, and the fan and electric afterun pump run for ten minutes after switching off and then the relay switches them off. Ten minutes is a bit too long but maybe the relay is adjustable in some way? I havent looked.

By the way, before this my afterun pump and fan never came on no matter how hot the engine was, and I changed the switch too .

Mark.

[martinjs]

Ben,

By the way, before this my afterun pump and fan never came on no matter how hot the engine was, and I changed the switch too .

Mark.

ok, i'll try this too, mine has never worked, the relay is the only thing i havent changed, it comes on if you connect the 2 terminals (cant remember if it was hot when i did this), suppose its a good way to test the relay.

so in theory if i connect these up when its cold nothing should happen?

i did think about taking the switch off the water manifold and turning some of the brass off the end so that it triggers a bit earlier, dunno how much it would take though 0.2mm maybe, bit of trial and error really.
its a trick the renault 5 turbo contingent do to make the main fan come on earlier.

martin

[s2avant]

Where is the switch?

Pardon my being lazy but I'm in a bad mood as I was beaten by a vauxhall astra on my way home!!! (damn these boost problems).

I'm going to need a bigger pad to write down the registrations of all the cars that have made me look like a sunday driver so when it's fixed I can show them how it should be done

I'll look into the relay and see if I can find any info on the timer. I'm running a big diesel battery and 120A alternator so ten minutes shouldn't be a problem on mine but it could be of use to the group.

I've only ever had run on pump and fan come on once. That was during last years heatwave after a very long drive.

Ben

[martinjs]

Its screwed into the water manifold, its the smaller one of the 2 there, bit awkward to get at but easier for you aby'ers.
someone did mention ages ago about a relay from a seat that was activated earlier, but martynf couldnt find one.

[s2avant]

One last question, what size fuse did you use? A fuse gives a second level of protection so I'll want to dit rather than short it out.

Seat relays have timers in them. I'll look into those as well, they do different timers depending on whether the car has leather or cloth etc.

Ben

[Mark Halligan]

so in theory if i connect these up when its cold nothing should happen? martin

Martin,

it will work even if the engine is cold, as you will be taking the temp switch out of the circuit, far from ideal I know .

Mark.

[s2avant]

Maybe a lower temp switch could be fitted. I'll stick it on my to-do list. Can't see me doing a lot of real work tomorrow

Ben

[Mark Halligan]

One last question, what size fuse did you use? A fuse gives a second level of protection so I'll want to dit rather than short it out.

Seat relays have timers in them. I'll look into those as well, they do different timers depending on whether the car has leather or cloth etc.

Ben

Ben,

I used the same rating as the one in the fuse box for the water pump, can't remember what it is now though.

I remember something about a switch that comes on earlier too, but couldn't remember what it was off, that might be a better option as what I have done is not really a good way of getting it too work as it will come on at all temps.
Also the factory switches all switch off if the temp gets too high as in an engine fire, so that the fan does not feed the flames with air.

Mark.

[s2avant]

Right, I've done some investigating and found the following. They are all 2 pin M10x1 temperature switches.


054 919 369 B-----97/110ºC (standard)

035 919 369 B-----30/40ºC

035 919 369 C-----55/65ºC

055 919 369 C-----65/75ºC

034 919 369 ------85ºC

034 919 369 A-----90ºC



Not sure whether the last two would be any good as they don't have dual temparature ratings. To be honest I'm not sure what the two temp. ratings are for.

Ben

[martinjs]

ok, just connected the terminals and it came on for 8.5mins.
agree, a different switch would be great, but at least i've got it working.

heres what s2central states:-

"F98 - TCP Thermoswitch - This device is located alongside the multifunction temp sensor (F76) on the underside of the water rail that runs below the inlet manifold. This switch closes at 106-112C and opens at 94-105C. According to SJM, this device is clever enough to open if the temperature exceeds 130C in a horrible scenario such as an engine fire. Best take on the part number is 054-919-369B - this supersedes earlier part numbers."

martin

[martinjs]

ben, why is there 2 types of each switch with the same part number?