My 1990 volvo 240 DL begins to overheat if it sits still to long(traffic, red lights) after driving it for awhile. When it does overheat, it begins slowly. When I start driving it or riving the engine it will eventually cool down. I've changed the thermostat, did a radiator flush, and placed a new clutch fan(the tropical version which cools more) on but still have the problem. What's left, the radiator? If so, will the Nissen have enough rows to keep it cool in Texas?

Thanks,
-Darin

 

The easiest way to test a rad is with an IR heat thermometer. A clogged rad will have hot spots where the coolant enters and cold spots where clogs are. The temp difference can be felt w/ your hand but on a 240, you cant get to the rad w/o chopping your hand in the fan. The stock Nissens will work fine on an n/a motor. Only the turbos really need a 3 row. Make certain your condenser is clean and a belly pan helps cooling too. Where in TX are you?

 

My step dad had one of those thermometers where you can aim and get the temp, and we didn't find any noticeable cool spots. I am in Austin, Texas. Where is the condenser located at?

Also, is it possible that there is air in the radiator from the flush? This problem doesn't happen consistently...just randomly.

 

The condenser is the a/c portion that sits in front of the radiator. Obviously it blocks a portion of air flow to the radiator...keeping it clean minimizes the restriction. Volvos can be picky about air bubbles...the best thermostat such as a Wahler has a hole on the perimeter to allow air through. Still, it would have to be one Hell of a bubble...still really sounds like the radiator. Occasionally, I run into rads that are fairly uniforly blocked and the IR gun doesn't really pick it up. In those cases, customers are always p/o'd because we tend to first replace fan clutch. Since you're using the tropical fan clutch (which rocks by the way) it almost has to be the radiator.

 

I ordered a Nissen radiator for it. Is there anything special I need to know when I actually install it?

Also, to get the air out after I am done- I was told to to slightly loosen the drain plug on the manifold to let the radiator fluid seep out when the engine is running. Does this sound like a good plan?

 

I think you mean on the block rather than the manifold...seems like that might work. It's somewhat rare to get a bubble that doesn't clear itself though.It's always good to make certain that, if your t-stat has a jiggle valve, it is at the highest point of the install.

 

Ya, when I installed the thermostat it had some kind of mark that I was supposed to install pointing at 12 o'clock. Will the transmission hose unbolt ok or should I expect problems?

 

The cooling lines can be tight sometimes. It wouldn't hurt to spray them a day or two ahead w/ PB Blaster or other penetrant. Also, using a line wrench instead of an open wrench makes life simpler.

 

I haven't installed it yet...but I forgot about the hoses. I put new hoses on about 6 months ago when I did a radiator flush. Do you think the hoses are still reusable? Or is it likely the rubber already melted on the connected port?

 

They should be fine...if they melted you have more issues than a radiator!