Overheating?

rfenwick · 8th May 2011, 16:15

Hi everyone,

My Rover 75 developed a coolant leak which I failed to notice until the first warm day of this year, when the engine temperature alert came on in a queue of traffic - got it straight in to the garage who diagnosed a leaking thermostat and some corroded piping.

Within a few weeks, the leak was back. For the moment I am keeping the coolant topped up with water (not mixed with antifreeze). It doesn't need topping up very often - a cup full of water every couple of weeks.

I live in the country but was driving around town yesterday, and the fan (fast speed) was kicking in regularly in queueing traffic. When I parked up and put the thermostat in diagnostic mode the engine temp was about 118.

A few questions if I may. Is the fan kicking in to keep the engine cool on a 23 degrees C day normal? Should the fast fan sound that loud? (pretty similar to a hoover's volume) I suspect I know the answer already, but best to ask! At the moment I'm guessing the car is going to overheat regularly when we get up to 30 degree days.

R

rfenwick · 8th May 2011, 16:18

Attaching a photo of what I have self-diagnosed as a return of the coolant leak - have verified it's not the aircon pipes or anything like that

stocktake · 8th May 2011, 16:19

It sounds like your fan is only operating on fast speed. fan should come on at around 100 deg and stay on until 95. do a search on cooling fans loads to read 118 is FAR too hot.

chrissyboy · 8th May 2011, 16:31

is the fan running for a while after you have parked up ?, i would expect it too ,those temps it is reaching is getting too hot for the heads so heat soak will accure where the fan wll run on high speed to reduce the heat to the head . should sound like a hoover craft... as for the leak i would check all the hose`s and look around the clips to the hoe as they cut into the hose making it leak ,and its hard to see ... also check the coolant tanks cap...as the header tank is above where the leak looks like it is ...

Cymrudragon · 8th May 2011, 16:34

Quote:

Originally Posted by rfenwick

Attaching a photo of what I have self-diagnosed as a return of the coolant leak - have verified it's not the aircon pipes or anything like that

coolent pipe leaking around expantion tank area, or rad...look at the bottom corners of the rad for a drip. also the metal pipe directly below the rad rusts so check there as well.....also as above expansion cap.... finaly i always seam to top my car up as well but this is due to small coolent tank coupled with high running tem of the kv6 , mainly due to short trips....etc..

rfenwick · 8th May 2011, 18:12

Thanks for your help everyone - I'll get the car off to a garage who know what they're doing. The garage who did the last job expected it to be a 2 day job and kept the car for seven days

SD1too · 8th May 2011, 18:27

Hi Rob,

For a 1999 V6 like yours (and mine) I reckon that the overheating is due to low and medium fan speed failure (leaving only the high speed which you've heard running). The small pool of coolant which you've photographed is probably normal ejection through the expansion tank overflow.

What has happened is that one of the earth brushes in your fan motor has worn to nothing. If you relish a mechanical and electrical challenge you can repair it for the price of 2 gallons of unleaded. The other option is a new fan motor assembly; either the MG Rover 2 speed equivalent or an aftermarket Kenlowe model. They'll cost you three digit sums.

I'd recommend that you delay sending your car to a garage until you've discussed your options with forum member Jules who will know more about Rover 75 fan motors than they do.

Quote:

Originally Posted by rfenwick

Is the fan kicking in to keep the engine cool on a 23 degrees C day normal?

Yes, when the car is stationary.

Quote:

Should the fast fan sound that loud? (pretty similar to a Hoover's volume)

Fast speed, yes. Slow speed is respectably quiet.

Simon.

scouseeric · 10th May 2011, 03:56

When you first took the car in and they diagnosed a thermostat leak and corroded pipes, did the garage do any repairs? It sounds like an airlock in the coolant on top of the fan fault.hth.

Eric

rfenwick · 10th May 2011, 05:34

Hi - yes they did, a new thermostat and new piping. The suggestion about fans sounds very plausible - am I right in thinking that with the engine running and air conditioning on, if I peer through the bumper grill I should be able to see the fan spinning round (medium speed)? It wasn't spinning at all during a quick check yesterday with the aircon on.

Mr Edd · 10th May 2011, 06:07

One place to check is under the expansion tank. Took Me a long time to figure where this slight leak was coming from...

Where possible replace all the old hose clips with Jubilee type ones.

Edd

8th May 2011, 16:15	#1
rfenwick Newbie Saloon 2.5 V6 Club Join Date: Jan 2010 Location: Sudbury, Suffolk Posts: 10 Thanks: 0 Thanked 0 Times in 0 Posts	Overheating? Hi everyone, My Rover 75 developed a coolant leak which I failed to notice until the first warm day of this year, when the engine temperature alert came on in a queue of traffic - got it straight in to the garage who diagnosed a leaking thermostat and some corroded piping. Within a few weeks, the leak was back. For the moment I am keeping the coolant topped up with water (not mixed with antifreeze). It doesn't need topping up very often - a cup full of water every couple of weeks. I live in the country but was driving around town yesterday, and the fan (fast speed) was kicking in regularly in queueing traffic. When I parked up and put the thermostat in diagnostic mode the engine temp was about 118. A few questions if I may. Is the fan kicking in to keep the engine cool on a 23 degrees C day normal? Should the fast fan sound that loud? (pretty similar to a hoover's volume) I suspect I know the answer already, but best to ask! At the moment I'm guessing the car is going to overheat regularly when we get up to 30 degree days. R

8th May 2011, 16:19	#3
stocktake Vis Whiz Rover 75 2.5 auto Saloon Join Date: Jun 2007 Location: LEEDS Posts: 20,591 Thanks: 2,057 Thanked 3,056 Times in 1,621 Posts	It sounds like your fan is only operating on fast speed. fan should come on at around 100 deg and stay on until 95. do a search on cooling fans loads to read 118 is FAR too hot. __________________ Dave... Lost a few stones and a Gall Bladder and part of a bile duct and all of my dignity in the suppository incident

8th May 2011, 16:31	#4
chrissyboy This is my second home lovely little ford focus. Join Date: Jul 2009 Location: East Dulwich Posts: 7,877 Thanks: 2 Thanked 82 Times in 68 Posts	is the fan running for a while after you have parked up ?, i would expect it too ,those temps it is reaching is getting too hot for the heads so heat soak will accure where the fan wll run on high speed to reduce the heat to the head . should sound like a hoover craft... as for the leak i would check all the hose`s and look around the clips to the hoe as they cut into the hose making it leak ,and its hard to see ... also check the coolant tanks cap...as the header tank is above where the leak looks like it is ... __________________ [ I'm really confused. -I keep dreaming I'm an insomniac

10th May 2011, 06:07	#10
Mr Edd From the Horses Mouth 2012 Honda Oddessay and 1996 Ford Ranger Truck (Splash) Join Date: Oct 2008 Location: Fort Myers, Florida Posts: 1,045 Thanks: 0 Thanked 13 Times in 7 Posts	One place to check is under the expansion tank. Took Me a long time to figure where this slight leak was coming from... Where possible replace all the old hose clips with Jubilee type ones. Edd __________________ I'd be dyslexic if I could spell ti.

8th May 2011, 18:12	#6
rfenwick Newbie Saloon 2.5 V6 Club Join Date: Jan 2010 Location: Sudbury, Suffolk Posts: 10 Thanks: 0 Thanked 0 Times in 0 Posts	Thanks for your help everyone - I'll get the car off to a garage who know what they're doing. The garage who did the last job expected it to be a 2 day job and kept the car for seven days

10th May 2011, 03:56	#8
scouseeric Passed Away 75 contemporary se cdti Join Date: Dec 2010 Location: Liverpool Posts: 1,579 Thanks: 0 Thanked 0 Times in 0 Posts	When you first took the car in and they diagnosed a thermostat leak and corroded pipes, did the garage do any repairs? It sounds like an airlock in the coolant on top of the fan fault.hth. Eric

10th May 2011, 05:34	#9
rfenwick Newbie Saloon 2.5 V6 Club Join Date: Jan 2010 Location: Sudbury, Suffolk Posts: 10 Thanks: 0 Thanked 0 Times in 0 Posts	Hi - yes they did, a new thermostat and new piping. The suggestion about fans sounds very plausible - am I right in thinking that with the engine running and air conditioning on, if I peer through the bumper grill I should be able to see the fan spinning round (medium speed)? It wasn't spinning at all during a quick check yesterday with the aircon on.