Overheating
 

I was looking through the forums but none were for my car. every so often my 99 cobra will overheat to above the centerline and will cause my coolant to bubble up and come out through the coolant tank. it leads me to beleive my thermostat occasionally gets stuck but im not an expert. any ideas? also if you can tell me what the best thermostat is to use, i was thinking of a 160 but if you think its not worth it, the 180 and everything i need to get my system functioning properly. i also need to know where the thermostat housing is located, noting that the 4.6 DOHC is different from the SOHC because its not up top where it claims to be located.

Before you go and buy something you may not need I would check to see if its working first.

Get the car warmed up to normal operating temps. While its warming up feel the upper radiator hose. It would be cool and have no pressure to it. Once the car is at operating temp the hose should become hot and very firm. This is because the stat has opened up and is letting coolant flow through. If the upper hose never gets firm and hot then the stat has failed and is getting stuck. So check that first before you go out and buy anything.

Your car might just need a simple cooling system flush and some fresh coolant.

ya i did all that but its only every once in a while that it actually overheats, normally it runs fine then all of a sudden it seems like it just sticks shut, i let it sit n works fine, so maybe a flush is in order, but i do want to put in a lower temp therm but i dont want to worry about my cooling fan being messed up from the temp changes.

i have a similar prob in my 95 v6
it never actually overheats but it goes all d way to the last white line
i have new thermostat radiator hoses and water pump

Make sure your "burping" the system correctly when working with the cooling system. You can get air pockets within the system and that will cause it to overheat. Its easy to forget this step, alot of people do

how do u burp the system?
didnt no bout this

With cobras, there is a port on the coolant cross-over. You loosen that port some and it will release the air. There is a good write up on how to do this step by step on modularfords and svtp i think

ya its the metal radiator link hose right in front of the alternator i believe

If you do get a cooler temp stat be sure to not go below 180*. Otherwise the car will never get up to operating temp and you will be in closed loop mode (warm up mode) and burn tons of extra fuel for no reason.

So 180* is the lowest you want to go.

There is also a guy that sells stats for the 4v cars that are supposed to be great. He modifies them to stay closed longer for faster warm up's and then open better for more flow or something for better control of the temps. Let me see if I can find it for you later on.

so if i get a 180 i wont have to get something to change out my cooling fan temp switch or anything?? i can just put it in and go?

Yes, but you won't get the car as cool because the fans won't be on at such a low temp. You will still get some better cooling from it.

Question: Has anybody here used red line "water wetter"? If so, what were the results?

One of my coworkers at autozone does on his vette and he swears it runs about 10-15* cooler. Whether it does really or not, I couldnt tell ya. I would just invest in a 180* and call it good.