I have a volvo 240 1991 with 143,000 miles. I've had it for about three months now. I've cleaned the throttle body and the flame trap, changed the oil, the brake fluid, replaced the voltage regulator, spark plugs, and the alternator, power steering and AC belts (they were all pretty worn). I thought I was good for the winter (though I'll probably be flushing the tranny fluid soon). Recently, I had the hood open and noticed that my coolant level in the reservoir/expansion tank was rising; it was in between min and max, and now it is well above the max. I looked at the fluid today and though it was green there was a definite tinge of black.

I keep my eye on the oil temp. and it seems to stay around normal. Is it a bad idea to be driving it if I keep my eye on the temp?

Any ideas? How should I proceed in diagnosing the problem?

Thanks,

Jimmy

I used a turkey baster to take fluid out of the reservoir and I drained some coolant out of the drain petcock. The reservoir looked off green but mostly old. The coolant from the engine block (petcock) looked old as well (there was some sediment in it), but it didn't really look oily. Unless a very, very thin layer of something that slightly resembles oil, qualifies as tranny fluid in the coolant. Are there other things I should check or tests I should run? Do you still think the radiator is gone and that the two fluids are mixing?

Jimmy

The short answer is very wary trial and error.

The long answer is, cover your butt. Do the tranny fluid flush because it is a good idea AND it gives you a baseline of perfect pink fluid. Do a full coolant change because it give you perfectly clean coolant.

Total cost for these two normal maint items is about $50-60. Money well spent even if it ends up the whole thing was operator error (coolant increase was nothing more than normal thermal expansion coupled with parking on less than level surfaces).

Three of us have said it but I will re-iterate, if you have an hint after this process that you have coolant and tranny fluid co-mingiling, stop driving and replace the radiator right now!

Hi,

Once you are sure (don't drive it!) they're mixed get yourself a new radiator, some coolant, lots of transmission fluid and make sure you flush both coolant and transmission really well.

You might want to change the thermostat, hoses, any other cooling system parts depending on condition.

If it was me I think I would even go so far as to order some Auto RX and follow the instructions for running it through the transmission.

Just no driving whatsoever, you risk a dead transmission.

Travis

90% sure you have tranny fluid in your coolant from a failed tranny cooler in the passenger side tank of the radiator. Please confirm immediately as this also means coolant in the transmission fluid which is the #1 killer of our otherwise bulletproof automatic transmissions.

Thanks for your response. How would I confirm this? What I can say is that I'm 99% certain that when I checked the transmission fluid earlier it was a little below minimum. I went to Advanced Auto Parts to get some tranny fluid and when I went to fill it up and measure it, it was above the maximum level. When I checked the tranny fluid it did have a brownish color to it.

How should I proceed?

Thanks,

Jimmy

You should see trans fluid (oily substance) in the reservoir, if so you need a new radiator and a complete flush of the trans fluid.

Stop driving the car until you have resolved the problem.

Dan

I must reiterate...do not drive the car until the issue is resolved unless you want buy and install an used tranny in the very near future.

Drain some coolant into a clean, preferably light colored, pan using the drain petcock on the block is possible. You will see the oil slick. Might see it in the coolant reservoir but might not.