Electric fan failure

Post by **DARK STAR** » Thu Jul 25, 2019 9:16 am

This is not yet another problem on the GTC, I sold it.
It's the boss's Calibra which I always think is a modern car (it's the newest we have!) but is even so nearly 30 years old ...

The car boiled just after driving into the garage yesterday and I noticed the fan wasn't running.
Amazing that it didn't happen in the back country half an hour earlier.

Today I checked the fan, then the connections.
When I short out the terminals of the temperature sender the fan starts.
Presumably this is the culprit ? but it is so hot that my brain has boiled just like that car and I need a second opinion.
About the car, not my brain.

Post by **scimjim** » Thu Jul 25, 2019 9:19 am

I’d say that was the culprit, yes.

Post by **Terry H** » Thu Jul 25, 2019 9:20 am

If you connect both wires on the switch on the radiator and the fan runs then the likely culprit is the switch.
Regards Terry H

Post by **DARK STAR** » Thu Jul 25, 2019 9:30 am

Many thanks for the quick responses !

Post by **DARK STAR** » Thu Jul 25, 2019 9:44 am

Nothing is ever simple.
The only place I can find this part on internet is on a russian site

https://www.avito.ru/moskva/zapchasti_i ... _769252956

Can anyone help with another source / alternative ?

Part number ELTH 264207

Post by **scimjim** » Thu Jul 25, 2019 9:56 am

Check some of these?

Post by **DARK STAR** » Thu Jul 25, 2019 6:19 pm

Ok thanks I found one.
The secret is not to search Calibra and certainly not the part number

The site where I eventually found it lists six equivalent model numbers - but not the one I have, which is I think genuine Opel.

Post by **DARK STAR** » Tue Jul 30, 2019 9:06 pm

The part arrived ok and is the right size, but it has three terminals instead of two on the old one.
The plug also has three terminals but one was not connected before.
I connected it anyway and ran the car up to temperature - and beyond.
The fan didn't even notice.

I checked again the connections, shorting pins 1 and 2 kicks the fan into life.
I wonder if the pin-out on the three-pin sender is different, if it works on pin 1 and 3 instead of 1 and 2.
Anyone know?
And if I bridge 2 and 3 will I damage anything?

If I don't fix it soon I will have to go and buy paving flags and cement in the Coupé ...

Post by **philhoward** » Tue Jul 30, 2019 9:18 pm

If it’s got 3 pins my guess is for a two speed (or twin) fan which GM liked - one at “hot” and one at “nearly boiling”.

Do you posses a Haynes or similar manual (if not for a Calibra then the equivalent Vauxhall Cavalier/Opel Vectra)? The wiring diagram might give a clue - may be single speed/fan on the 8v and twins for the 16v?

Safest would be testing it out of the car using a meter and a pot of boiling water - at least one pair of contacts should close by about 95 degrees, be it 1&2, 2&3 or 1&3..

Post by **DARK STAR** » Wed Jul 31, 2019 6:16 am

Thanks Phil
Seems a strange idea to switch on one fan than when it doesn't cool the engine switch on another

I'll try to test it on the car - I've already killed half the 'lawn' in front of the garage with antifreeze.
If I connect trailing wires to the sensor before heating everything up it shouldn't be too hazardous.

Post by **gtcse8** » Wed Jul 31, 2019 7:59 am

Chris the Two stage cooling system was also fitted to Middlebridge.
Pain in the arse to get it to work correctly and cool the car quickly.

I converted one to a single switch type that cuts in around 85 instead of 95.
It was Ironically from a BX, which is also the high flow fan that I replaced the rather large but not very powerfull Facet type that in place.

The BX also comes with Two or Three Lucar tabs, so I picked the twin type and the car ran beautiful all the way and back from Silverstone this weekend for the 30th MB Anniversary.
And as it uses Lucar tabs it was simples to wire in and test.

Post by **DARK STAR** » Thu Aug 01, 2019 8:12 pm

Well, either I'm missing the point completely or the new sender doesn't work

This is basically a temperature-activated switch, right?
So as Phil says at least two of the three wires should make contact at 95-ish degrees.
I ran the car up to 100 degrees on the gauge, which has always been pretty accurate.
And no contact whatsoever between 1&2, 1&3, 2&3

Unfortunately I threw away the carton so can't send the bloody thing back.
But perhaps I should look at Jim's links above ...

Post by **DARK STAR** » Sat Aug 03, 2019 11:54 am

Have now wired the fan permanently on

and ordered one of these
https://www.ebay.co.uk/itm/Radiator-Fan ... SwdAxZbUWI