Dirty coolant and burnt smelling trands fluid on a 96 Century Custom 3.1L V6

[DriftinDraggin]

One again my car is a 1996 Buick Century Custom with the 3.1L V6. It has 143,000 miles on it. I have been having trouble with my coolant since I bought the car a little over a year ago when it had 115,000 miles on it.

When I got it new coolant and transmission fluid was present. The radiator was also claimed to have been changed. Since then I have had to refill the coolant resevoir and radiator at times due to coolant loss.

Contamination of the coolant appears in dark black flakes floating in the coolant resevoir and appears somewhat red-but mostly green in color.

The coolant does not appear to be going on the ground or out the tailpipe via (white smoke). I know this car has a history of overheating and warping the head which causes problems. Is this possible without seeing white smoke coming out the tailpipe or having any other obvious symptoms available? Is this what the dirty coolant means?

It idles a little rough but not enough to really be disconcerting for a car with 143,000 miles on it. The only thing I notice is the temperature gauge. It appears to be pretty close to the C when I cruising but seems to spike to almost half way when in stop and go before the fan kicks in to cool it off.

The other thing I am worried about is the transmission fluid. It appears to have gotten somewhat dirty since I purchased the century. Also it smells like it's burnt. Does this car have a history if problems with coolant and transmission fluiid mixing due to a faulty radiator? Would any other symptoms be exhibited by this if it happened? Or do I just need to change the fluid? Or is this a symptom of something larger? Does this car have a history of radiator problems?

Most of all I'm wondering if it's worth keeping it or just buying a new car. My local mechanic said a head job would cost 700. He suggested I just sell it and get a new car.

Any help would be welcomed

[GM Line Rat]

Remove the 2 transmission cooling lines going to the radiator and look for signs of any coolant being mixed with the transmission fluid when the trans fluid starts to run out? You can "Lightly" blow some compressed air thru 1 of the trans line cooling fittings in the radiator also and see check for any signs of coolant mixing as the rest of the trans fluid comes out. If there is, you need a new radiator. You'll also need to flush the entire cooling system and I would also drop the transmision pan and drain the fluid out of it, change the filter and re-fill with new trans fluid......If there's any coolant in the trans fluid, it also in your trans pan too by now. Also, how does your engine oil look? Check it while th car is cold and turned off......Does is look like chocolate milk? If it looks normal and the oil level is good (Not overfilled).....Coolant is not mixing with the engine oil.

[DriftinDraggin]

I took my car over to my transmission guy's shop and he said the trans fluid looks alright. I also thought to get the cooling system pressure tested since I saw a deal in the paper at a local shop for around 30 bucks. I asked pep boys if they do engine flushes and they don't now because I guess they were having issues with the process blowing head gaskets. If I find it's something with the head or the bloc, are any of these liquid head gasket repair fluids really effective? They claim to seal cracked heads, stop block leaks and repair blown head gaskets. In any case I'm going to take the car in on monday to have them do the pressure test on the cooling system and replace the coolant.

[90BuickSlab]

from what i hear the repair liquid will help you get a few more months out of it depending on how much you drive it.