I have a MK 1 caddy changed to AAZ 1.9 motor. I see the engine temps rising to much higher levels any time I climb a hill or in traffic. I have seen 6 blade fans for sale rather than the 4 blade in have now. Is there much to be gained to change to the 6 blade from the 4 blade? Can I just change the fan blade w/o changing the entire motor and fan assembly. Any other improvements for cooling. Are larger radiators available?
Fan size and number of blades will move more air, check for some measure like CFM's or the like. You can get a bigger as in fatter radiator that would hold more volume and thus cool better. With the temps dropping like a rock across the states I would think heat would be a good thing. Many are stuffing cardboard in front of the radiators now to get the engine to warm at all. -30 and -40 in upper Mont. and ND. Moving east as you read this.
Got longhandles?
I would buy 1 or 2 slim fans off ebay. They move a lot more air than the stock fan. And they are cheap. $40 or so shipped. They a very decent and I have owned several and never had a problem. If you have a 2 speed fan you just wire both speed wires off the thermostat to the one power wire off the slim fan.
You can also mount the fan in front of the radiator as a push fan and free up lots of space in the engine bay.
Sent From Outer Space
Big oil cooler helps. I suspect you need a radiator cleaning if the stock stuff can't cool an AAZ though, it should be alright.
Mine has been fine for years, oil temp was the issue I had with turbo diesel VWs. Big cooler fixed that.
Brother has an AAZ swapped mk1 Jetta, the stock 1.7EN gas engine cooling system has no issue cooling it.
Pump is tuned up, and it rolls some coal too.