Too hot for madeline

[Julian64]

This hot weather is showing the ineptitude of the cooling system in my 4.5. Maddy is running at 95 to 100 virtually all the time with short bursts of 90 when above 80mph. If I hit traffic the car climbs to 105+ I've bled the system twice recently with no sign of air on the second attempt, and no water loss. Fans are working, and cut in at 100 so my temp gauge must be reading okay. I assume as the cars only done 15000 that its unlikely to be sludge build up in the rad. I was told that waterpumps never go on the cerb so its down to the radiator.

Anything I've missed before I look for uprated radiators. Anyone tried covering the exhausts?

Joolz, did you do radiator replacements. If so how much and how good are they?

[j_s_g]

Are you sure that the temp. guage isn't at fault? My guage reads 105 in traffic, the fans cut in at 100, but I've had the accuracy of the guage checked properly and it's about 8 degrees out.

[Phil Dicky]

Funny that my daughters called Maddy and she is constantly running at boiling point just like her mother. God my life is bliss.

[Julian64]

Sorry I thought that the fans were designed to cut in at 100 and use a different temp sensor, so to hear them and then see the car indicating 100 was confirmation of the dashboard temp gauge?

[j_s_g]

Julian64 said:

Sorry I thought that the fans were designed to cut in at 100 and use a different temp sensor, so to hear them and then see the car indicating 100 was confirmation of the dashboard temp gauge?

I honestly don't know whether they use the same one or not. However, if there are two, they may both be wrong?

[Byff]

I think your car sounds ok.

As long as the fans keep bringing the temp back down/won't let the temp rise anymore, then everything's working.

[jnr]

Hey,

I think you have nothing to worry about, mine does the same and its not a problem.

If it gets to 110 then you're definately in fro some trouble!!!

Hope all is well...

Jnr

[ro_butler]

I always used to get worried about this and constantly took the car back to te dealer, only to be told everything was fine.

The fans are controlled by the ECU which uses a different sender to the dashboard temp gauge (mechanical capillary type).

Take the car to a dealer and they can plug a laptop into the ECU which will tell you what temp the ECU thinks the fans are cutting in at, and how different this is to the temp gauge.

For the record my fans come in at 90C but the gauge is reading 98C so it overreads by 8C. This is not uncommon. In this weather the fans may well be on almost permanently unless you are going quickly so nothing to worry about.

Rob.

[mashie]

My Cerbie became a steam engine while stuck on the M25 today. Slowly the temp gauge started to bounce into the oil pressure meter. Then the part you really don't want should happen, a big white cloud of steam coming out under the left side of the bonnet

After parking under a bridge for 30 min the temp went down to 100 but on the way home it was bouncing between 100 and 115!!!

Now the question is, do I need to have the system aired or will it be sufficent to fill it up?

[gazzab]

Id say get it to a garage asap!! You dont want an AJP overheating!

[ro_butler]

Mashie,

In general I would switch the engine off if it goes over 105 since you run the risk of warping the cylinder heads if you don't. This isn't unique to cerbies, my mate did it on his citroen saxo (few years ago now).

Seems quite a few people are having problems with theirs, mine was running at nearly 100 for the entire journey on saturday (just below the point where the fans cut in) in slowish moving traffic.

And as Gary mentioned, get the car to a garage.

Rob.

[mashie]

Cheers, I will call the dealer tomorrow. Only had this car for one week...

[Julian64]

Thanks for the advice. Will do the ECU thing at the weekend. It worries me however that my temp gauge goes from 80 to 105 and back down to 90 within 20-30 secs. The minute I go under 60mph I rely souly on the electric fan to get me where I want to be. I daren't switch the Air Con on at that point. Doesn't fill me with confidence. I thought that may mean bleeding but no sign of air. I get the feeling the cooling is rather marginal on the cerbera. And with such a peaky engine thats scarey. I feel I should do my bit to increase its longevity.

I used to have a similar problem with the Cobra running a 6lt Chevy. But increasing to a three core radiator fixed that and I now rarely have the fans coming on with that car.

I think joolz does a replacement radiator but he's stayed uncharacteristically quiet so far on the details.

[mudstud]

Have noticed the same thing, temperature can go from 105 to below 95 in 10-15 seconds. Thermodynamically speaking don't think it is possible to cool engine and contents that amount in given time frame. Therefore...must be gauge, air in system, or temperature readings not representative of true engine/water temperatures (pockets of hotter water going round or something). For my car I suspect the latter although have not investigated. Perhaps better water pump needed to ensure flow of water to rads required?

>> Edited by mudstud on Tuesday 12th August 09:48

[ro_butler]

I agree with both of you. The cerbera cooling is marginal (especially on the RR if it under extreme load).

I share your concerns about funny readings and relying on the fans. However I have been worrying for 2 years and nothing bad has happened at all.

The temp gauge seems to be a bit crap but I think the water pump is fine. Replacing the rad with an upgraded one should make things much better. Joolz does an upgrade or you could have an ally one made (with more cores) by Alan Docking racing. Or failing that Bert at CDL racing had an ally rad made by Serck, not sure where he got it from though.

Rob.