Thread: Troubleshooting Summer Overheating

The Revs don't drop "much" but I can certainly tell the difference between Air Con Running and Air Con Not....

That's about normal then I guess! Not sure about the tech side of things but mine will idle at around 700rpm then jumps up to 900rpm when the ac kicks in - is there some sort of electric compensator that adjusts the revs with ac on that may not be doing its job in your case?

Just throwing random ideas out there!

Further diagnosis in Hot Weather today has yielded the following results

Air Con Off in 37 Degree Ambient Temp (Idling as if Stuck in Traffic)
Engine stays at middle of Temp Guage as normal (30 Minutes Duration)

Air Con On in 37 Degree Ambient Temp (Idling as if Stuck in Traffic)
Engine Temp rises to first bar to the right of middle within 2.5 minutes
Engine Temp rises to 2nd bar to the right of middle within 5 minutes (End of White/Start of Red Area)

Turning off the A/C results in the temperatures dropping until back to normal operating temp within 2-3 minutes.

All of this was performed this afternoon in 37 Degree Ambient Temps at Stationary Idle. The Front Condensor Fans weren't operating during the "Air Con Off" Test as expected. When the Air Con was switched on these came on within 10-15 seconds and were fairly loud (as such expecting that they are blowing some air).

So.. What should I do next?
Better Condensor Fans?
Check A/C R134A Level?

A couple of thoughts, given that you appear to have seen to all the major components:

1. When the A/C clutch takes up and there's additional loading on the serpentine belt, is there any visible effect on the operation of VC fan?

2. I'd also check the integrity of the Engine Coolant Temp sensor and its connector (no dirt/grease etc) on top of the inlet manifold...it appears than even a small change in temp is being translated into a "large" change on the temp gauge. That's why I was wondering if you had an independent means of checking the actual temp increase rather than relying on the gauge.

cheers

VC Fan seems to operate the same whether the AC is on or off....
I've purchased a Laser Thermometer so I can ensure that the Radiator has an even temperature and also check temps of other areas in the Cooling system potentially.

I can feel the AC is struggling because as the overall system "warms up" the effiecency and temp of air at the vents is increasing as well with AC turned on....

when you switch the ac on, the condenser/evaporator (one in front of the rad, I always get the names mixed up) heats up to create a heat transfer for the aircon system to work. at idle with decreased water flow and air flow through the rad it heats up more as the efficency of the cooling system is reduced by the extra heat produced by the ac condenser. you need to check the temperature drop over the radiator, if its anything less than 20 deg then you need to beef up your cooling system, a solid state fan rather than vc one and a larger radiator will always help. if you go down the aftermarket route for another rad to be built avoid at all costs a close mesh core they do not let enough air through to cool properly. good luck

Surely requirements for aftermarket systems shouldn't be required. I don't see anyone else experiencing issues such as this so surely something within my System is the fault.

I will await what my Thermometer tells me before moving forward.

FWIW... I'm presuming you have put a gentle hose spray over/through the aircon heat exchanger in front of the radiator to ensure it's not clogged? (same with oil cooler?) Just a thought. Looking forward to hearing what the thermometer results are!
cheers