Thread: More overheating problems

Originally Posted by bee utey

Air cond shutting off is usually an overpressure thing. Have it checked, either the high pressure switch is faulty, the condenser is partly blocked, or it is overcharged. You tend to get lower pressures on the hydrocarbon HC12 gas too, in case you are still on R134A

Is that best done at an AC workshop, not the basic home mechanic?? or simple enough to do?

Do you mean the temp switch on the thermostat housing - either the green or yellow?? I have never changed either of those yet?

Its a 300tdi, gased with the newer stuff - which has never been as good as the original

Thanks

Dave
95 300tdi Discovery

Originally Posted by waltsd

Is that best done at an AC workshop, not the basic home mechanic?? or simple enough to do?

Do you mean the temp switch on the thermostat housing - either the green or yellow?? I have never changed either of those yet?

Its a 300tdi, gased with the newer stuff - which has never been as good as the original

Thanks

Dave
95 300tdi Discovery

You can pull out the grille and radiator and see if the condenser is blocked with dirt. You can check that the condenser fans are OK. But you can't check the pressures or the switch yourself unless you have a set of gauges and the skills to interpret the readings. BTW a pressure switch is not a temperature switch, totally different animals.

Originally Posted by crowey

Afternoon all

I have just purchased a 3.9 litre V8 disco 1998 vintage. I picked it up from Melbourne and drove it back to Adelaide to be regoed and then drove it to Newcastle for xmas.

Info.

There is an after market temp gauge sender unit fitted in line in the top radiator hose.and a dash mounted gauge.

The bloke I bought it off said he recently had the tanks off the radiator. So i am assuming he had it rodded.

Ambient temperatures during the drive were in the late 30's early 40's

After market temp gauge reads about 105 to 110 cruising along at 110-120kms an hour but does creep up to 118 with AC on

OEM gauge reads at just below halfway until temp gets up above 100 then climbs to about 3/4 from 105 degrees to 112 degrees
Above 115 degrees it sits on the upper white line. I usually shut the AC of at this point due to worries about cooking it.

Thermostat appears to be working at around the correct temp.

I removed two spotlights that were blocking the radiator a bit but have not noticed a big change. I also noticed a couple of thermo fans sitting in front of the Auto cooler that seem to me would block a fair amount of flow when you are cruising along at 110 km/h.

I had a search on here and found a few threads relating to high temps but no one seemed to be running at the temps im getting so now im a little worried.

My Questions are
1. what is the max operating temp these things should be run at?
2. Are the thermo fans an aftermarket add on and are they neccesary?
3. Can anyone recommend a better radiator to get rid of the heat quicker?
4. Should i pull the thermostat and bin it in the hopes of getting more flow?
5. Do all discos cooling systems run this close to the edge in terms of dissipating heat.
6. What else should I be looking at.

Thanks very much in advance for any help.

How did you set the timing? I would get your timing sorted as I am pretty sure that too much timing advance will make it run hot.

Slug.
Timing was set at 10 BTD with vacuum advance disconnected. Im hoping that is somewhere near where its supposed to be.