Discovery TDI300 overheating

Feb 04, 2007 11 Replies

My 1997 Discovery TDI300 (235,000 km) occassionally overheats - this usually occurs on very hot days (35C +) when loaded and pushing along at 110 km/h or faster with the A/C on. The temperature gradually rises from the halfway mark, where it normally sits, and creeps up. This usually takes a while to ocurr - probably 50-60 km before it starts heating up. I usually spot it pretty quickly and turn the A/C off and slow down to about 105 km/h and the temperature drops to normal quickly - but as soon as I speed back up and turn the A/C back on it starts to rise again.



I admit these are pretty tough conditions - I live in NW New South Wales where our summer temps are often well into the 30's and low



40's. Should the car be able to handle it or is gradual overheating simply a design limitation? Overheating is never a problem in winter.

If it is a problem (not design limitation) then possibilities I can think of are - some blockage of the radiator, A/C needs checking, thermostat. I have seen earlier post on this topic suggesting blockages in the radiator and the need to re-core them to fix the problem.



I'd be interested to hear if I'm being unrealistic expecting the car not to overheat and any suggestions.



Thanks



Lewis



If the radiator isn't in absolutely top condition both internally and externally this isn't too surprising. If I were you I'd get it recored, possibly with an extra row of tubes as well.

Remove tanks and clean rad tubes. All will then be peachy. Very common fault here in Oz.

-Craig.

Lew wrote:

Sounds like expected behaviour but the aircon will automatically cut out if the car gets too hot.

On or around Sun, 04 Feb 2007 18:44:35 +1300, EMB enlightened us thusly:

if you have aircon, the aircon rad can restrict the flow of air through the main rad (assuming it's the same as on the RRC, with the aircon rad in front of the main one). Check it over thoroughly and make sure there's as much airflow as there can be.

BiL Tim actually ended up removing the aircon (a more credible option for us in the UK than in NSW, I admit) on his RRC and this made for a lot more airflow in the main rad.

Have a look at the back of the radiator (difficult to see) - are the little fins all clear, and all there? The front can look ok when the back is knackerd.

Richard

Any leaves or debris in between the rads? Sounds like a new core or radiator is in order though.

Martin

Might be worth checking the stat is opening fully too. TonyB

Take the thing out!

And screw the vicous fan so its on permanent

On or around Sun, 4 Feb 2007 17:27:11 -0000, "tiscali" enlightened us thusly:

unnecessary if it's working properly. and if it's not, then the best option is to replace it.

do the discos have the additional electric fans that the RR had when fitted with aircon?

Yes the Disco has dual electric fans - they are working fine on my car and the A/C is cycling on and off as I'd expect.

Thanks

Lewis

Thanks to all of you for some helpfull suggestions - will go and have a good look at the back of the radiator, check/replace hoses and clean resevoir , see how she goes then maybe consider radiator recore.

cheers

Lewis

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required