Over heating KV6 how can you test if the engine fan is working?

[smallheathlad]

I have a R75 Connoisseurs 2.0l v6 x reg with 101k miles on clock. I purchased the car last December. No service history. I had the timing, drive belts and water pump replaced in January since then the car has done just over a 1000 miles.

Last week while stuck in very slow moving traffic the engine overheating warning light came on (the one in the centre console) also the temperature gauge went to 12 o’clock! Put the heater on full blast temperature gauge returned to 9 O’clock and the overheating warning light went out.

After letting the engine cool down, checked the radiator expansion tank it was empty. The outside of the tank is stained red from the antifreeze. Filled the tank to maximum filler mark i.e at the bottom of the bottom of expansion tank. Cleaned the outside of tank around filler cap.

Also checked for other leaks have been unable to see any. On removing the engine cover and with using a dentist mirror did find a little red staining in the V below the thermostat. (Yes I understand that I will need to get that replaced asap).

What I’m keen to locate is the possible cause of the problem.


Using the diagnostics accessible via the trip button to check the water temperature after the car has been driven for 5 miles while the car is moving at constant speed say 40mph the reading is between 85 to 88. In slow moving traffic the temperature reading increases to 92 then continues to raise to 100 plus. Soon as heater is put on the temperature drops by a few degrees. When car is moving at above 20 mph the reading drops to 89.

On checking the expansion tank, the outside is again stained red , I guess one of the issues is the filler cap seal is not functioning correctly.


Tonight while parked outside the house let the engine run until temperature reading was 104 the engine fan did not cut in.

At what temperature should the fan on a 2.0l v6 operate at?

How can you test if the engine fan is working? Many thanks

[stocktake]

Your fan has failed, on that year it will be the older 3 speed fan comes on at 100 and goes off 96

three options:

• replace with kenlow. small amount of re wiring reqd ( three and a half hours work)
• rebrush your existing fan, ( if all speeds have failed it is unlikely this will work) around 3 hours + brush fitting
• replace with later two speed, plug and play, just upgrade external resistor. again 2 and half hours

To test your fan start engine and select demist in the cabin. fan should run.

Edit: I see your in Birmingham. Pop along to the four ashes meet ( wolverhampton Sat or Sun) I am doing this very job helping another member learn about these cars, there will be a fair few of us there (30+ over the 2 days) your more than welcome

[Canonite]

You may have a faulty low speed fan. Do you know if you have the three speed fan or the two speed?

One way to check it is to start the car and press the demist button. If the fan sets off and sounds like a Lancaster bomber for a few seconds then cuts out it suggests the low speed has packed in. The high speed should have kicked in anyway over 100 and brought the temp back down.

[carlpenn]

As Stocktake has said, your Fan has failed. However I just wanted to highlight something ref your Thermostat.

Be sure to replace your Inlet Manifold Gaskets with new ones, or ensure teh Mechanic who does the work replaces them.

We paid a Mechanic to replace the Thermostat, he refitted my old Gaskets (Even though I had provided new ones) this then led to a leak from teh Gaskets - Although we did not know until it was too late as it was leaking out the front Bank side nearest the Belts, meaning the leak was out of line of sight. This led to the Engine being damaged to the point of our deciding to replace the Car

[stocktake]

Originally Posted by Canonite

You may have a faulty low speed fan. Do you know if you have the three speed fan or the two speed?

If the fan sets off and sounds like a Lancaster bomber for a few seconds then cuts out it suggests the low speed has packed in. The high speed should have kicked in anyway over 100 and brought the temp back down.

The age of the car almost certainly dictates it is a three speed, when the low speed fails it almost always takes the medium speed with it as they use the same neg brush. high speed would save the boil over if it was working

The pulsing medium speed is almost never present when the low speed fails on the three speed, only the newer 2 speed fans show this symptom

[Canonite]

Ah i see. They look a bit complex. I was surprised to find a 2sp fan in my T reg. Low speed is dead on that too as well as my ZT.

[stocktake]

Originally Posted by Canonite

You may have a faulty low speed fan. Do you know if you have the three speed fan or the two speed?

One way to check it is to start the car and press the demist button. If the fan sets off and sounds like a Lancaster bomber for a few seconds then cuts out it suggests the low speed has packed in. The high speed should have kicked in anyway over 100 and brought the temp back down.

Originally Posted by Canonite

Ah i see. They look a bit complex. I was surprised to find a 2sp fan in my T reg. Low speed is dead on that too as well as my ZT.

Flippin eck, i'm suprised your T reg has a 2 speed.
Just shows you never can make assumptions back at you
I suppose with many of the older ones being well over 70k ml now there will be many old three speeders already in the bin and two speeders fitted in their place.

having said that if it were a two speed the 2nd speed would have saved the boil over. ..

[Scribbler.]

Hello SmallheathLad, Bit of a contradiction here methinks; the KV6 is in fact the 2.5 petrol I believe and not the 2.0.L. Hopefully if ideed you have the KV6 2.5, mine took almost a year to overcome the over-heating problems. Thank heavens it now behaves beautifully after much haemoraging from my wallet. You name it I changed it ...costly, time consuming and total unreliability meanwhile. However, "She" behaves wonderfully now. Advice, fit a new Kenlowe fan, `Jules' can either fit or supply one at good cost and the job's fairy simple but best with 2 people. Good luck my friend. Mike.

[Rocket]

Kv6 comes as 2.0 litre and 2.5 Litre. I agree it sounds like the fan.

[Arctic]

Change Dominic's for the same reason yesterday after when i checked it only the high speed was working and that went while i had it running just faded out and stoped.

James (smallheathlad) well worth making the journey over you will learn loads as well as having a great laugh and meeting some other members late night camp fire is great too