Overheating Problem

[rollo_somerset@yahoo.com]

Hi, I have a Y61 ZD30 with about 440,000 on the dial. Recently while towing the camper trailer, not light, had an overheating when climbing through Cunninghams gap. Dropped it back a cog as usual and kept it running around 3000revs as normal but the temp guage went right up. Very unusual because it always runs mid range no matter what. Checked the water and all OK. Any suggestions.

[rusty_nail]

hey mate, im sure someone will come along shortly with some help to your question. can you please jump over to the intro section and introduce yourself, just a little something we ask here.

[4bye4]

Hi mate. I have a similar vehicle and towing my trailer up a long steep hill here in WA, had the same issue. i have a seperate temp gauge and was up to 120deg. Dropped speed to 40k to actually get over the top. Ok on the flat. The problem turned out to be mainly the viscous fan not working properly and partially blocked radiator. I have 250000 k on mine and as I had to take everything out to do the fan I took the opertunity to fit new radiator, new water pump, viscous fan belt tensioner and thermostat. In other word everything between the grill and the front of the motor. Now runs at 85 to 90 whatever the terrain, never gone over 91 deg and that was towing uphill on a 40deg day with air con going full tilt. Total cost about $1300, but the result is worth it. BTW, remove clean,rod and pressure test the old radiator about $850, remove and fit new radiator $980. While its apart do all the other stuff.

[the evil twin]

Hi, I have a Y61 ZD30 with about 440,000 on the dial. Recently while towing the camper trailer, not light, had an overheating when climbing through Cunninghams gap. Dropped it back a cog as usual and kept it running around 3000revs as normal but the temp guage went right up. Very unusual because it always runs mid range no matter what. Checked the water and all OK. Any suggestions.

440 K's... Your fan coupling will be shagged and while you check that out have a look at the base of the fan blades at the hub, I'll bet 99% that they are cracked.
If so, replace fan and coupling at the same time (easy job).

I'll also bet externally the the bottom portion of the fins of the Rad is clogged with with bug guts/mud/dirt and also, internally the Rad core is partially blocked.
Don't fool around with Rad flushes etc, pull it out and get it done professionally (either rodded or recored) and wack a new cap on while your at it.

In good nick the ZD30 cooling system works gangbusters