KV6 - Rebuild or not after overheat?
 

Hello,

With the KV6 if you said you were not losing coolant i would say air lock caused by incorrect coolant fill up procedure or a failed fan. However as you are losing coolant the classic spot in the KV6 to look for is in the engine V (look for any trace of coolant) and a failed thermostat housing O ring - more expert voices will no doubt advise as my engine is the 1.8 turbo.

Like you I purchased my car for the same reasons.

PS Too late now as you have replaced it but the MG Rover DMF is considered by many to be bombproof and rarely needs replacing.

Also HGF on a KV6 is a rarer occurence - it is my car the 1.8 turbo that , if not looked after, will end on HGF.:shrug:

If now: no coolant loss, oil loss/use blue smoke, no power loss, no water in the oil: just run it it is fine!:D

My KV6 had a few hot moments that I didn't catch straight away when bought, as the temp gauge is daft.
By accident as I know this, put a bluetooth obd reader in and monitored the real temperature. Way too hot, so started investigating.

Issue was the fan resistor was not ok, so the low speed didn't work causing very and too hot running for a couple of weeks :eek: Everyday doing traffic jams around Brussels (like M25, not nice).

Replaced the resistor and all is fine.
Now 15.000km further and it is still sweet as a nut and no coolant loss and a bit of oil leaking (so not disappearing) and no oil in the coolant, so happy and intend to use it until petrol is banned :}
Mileage is 210.000km and don't think it will break due to heat, if I replace the distribution belts on time (6 months left...)!

Rob

Thanks for your replies. Relatively reassuring with me thinking the worst. Glass half empty and all that!
Interesting that when the garage plugged in to try and sort out the engine management light a highlighted fault was a cooling fan speed issue so I shall follow that up. I can't unfortunately remember the other faults now (should have taken a photo!) beyond another saying misfire.
Not having posted on this or any any other forum before I wish I had done prior to the clutch repair. The clutch/gearbox specialist did say the flywheel was in a state and the clutch plate down to the rivets. No trace of a replacement clutch in the service history of 92,000 miles, and the last year spent commuting in London traffic I understand.
No sign of leaking coolant from the thermostat in the V so far, but something has been going on!
Appreciate your experience and any other sage thoughts.

Yes indeed Peter, this very much sounds as if you’ve lost some or all of your radiator fan speeds which is well known to members of this club! ;)

To prove this, start the engine and press the windscreen demist button on the air conditioning control panel. Now get out of the car and walk to the radiator grille. Is the fan running continuously? If not, or if it is pulsing on and off, then the cause of your mysterious coolant loss has been identified!

Simon

Think you own a good one. It is a Rover 75! Don't worry and enjoy. Just a few small niggles to sort out it seems.

By the way I do to enjoy them as well, owning 4 of them (3 are over 300.000km.. and daily drivers) and now bringing a Rover P6 back to live. Engine running again after over 18 years, just change fluids and get pertrol in the carb :D). Brakes are being overhauled now and it will be back on the road again in a couple of weeks. Proper engineering.

The SD1 is roadworthy ever since I bought it 24 years ago.

75s are of the same breed and quality cars, they are die-hards if you know them and old soldiers never die springs to mind...

If you need to entertain people on the road noise-wise, just do it with the noise of a Rover V8 in TVR :devil:

The 75 KV6 has a lovely noise as well, so that will do for me as a daily driver company car;)

Rob

You forgot to mention the MGR bleeding procedure which would be helpful to the OP Simon ;)

Brian :D

If not leaking from the thermostat, check the metal cooling pipes that run across the car just behind the front of the front sub frame. Also look underneath to check if coolant is leaking down. This could point to a leaking water pump.

I'd be interested to read any reports of KV6 engine rebuilds as my Typhoon has suffered a failure on the front bank.

I was very grateful to receive the reassuring responses to my initial post having suffered what I feared was a possibly fatal total and unexplainable loss of coolant and two episodes of overheating.
After much head scratching and consultations with my local garage and DMGRS and following replacement of all the plugs but with continued misfiring I opted to change all the coil packs. I had started this process with cylinders 1&3 but the car was still misfiring badly, so I ordered another four from DMGRS. Having read a few other posts on accessing the rear facing cylinders I changed the remaining coil packs and hey presto the engine burst into life, obviously firing on all six.

I took it for a twenty-five mile drive which became rather less cautious than I intended, and when the rev counter hit 6500rpm and the countryside began to pass by rather too quickly I thought it best to get home in one piece.
Within a couple of days the Check Engine light went out and all seems to have been well since. No untoward noises, temperature deviations, loss of coolant or signs of component distress.

Truly a miraculous escape and I cross my fingers all remains well.
Once more I'm very grateful for the support I received from the forum members who posted replies and to Mat at DMGRS. Thanks all.