I've got a 93 Cobra and it has a coolant leak around the water pump gasket. I'm going to be replacing the pump, gaskets and the timing chain next week as well as perform a coolant flush since it's been leaking. However the low coolant light came on today so I want to add some coolant to hold if over until I do the work. However I don't know what type to add. It currently has a green coolant but I don't know what I should add to it. I was thinking I could just add water but I thought you were only suppose to put in distiller water. Any advise would be great.

 

I do 50/50 coolant & distilled water.

 

Any particular brand of coolant or anything goes?

 

Prestone or store brand even like napa. some of the green stuff comes pre mixed 50/50. I do like Kinyodas if I cannot get the pre mix, 50/50 with distilled water . Distilled water is up to you, it is free of minerals that is in normal tap water. It is also very normal after you do this type of repair or any time you drain the coolant to have to add coolant to the overflow tank a few times. These cars can be a pia to berp the air from so it is common for it be low for a short time has air pockets work themselves out so don't be to alarmed.

 

a 50/50 premix is good, if you are in a colder climate a 70/30 will work out better when it gets real cold.

when you are in there replacing the water pump replace the thermostat and gasket also. it will save you some time and trouble in the long run.

make sure after you remove the bolts from the water pump, clean them off with a wire brush and apply a light coat of RTV (blue or orange) to the threads.

when you pick up the new thermostat take it out of the box and see if it has "bleed holes" in it... I remember the old FoMoCo parts didnt and i had to drill two small holes in the thermostat to assure the air was purged out of the block.

after you button everything up and add coolant, start the engine and let it get up to operating temp (you can tell when the fan clutch is no longer free wheeling and pulling warm air back toward the engine) and shut it off for about a half hour -- long enough for you to clean up your tools and wash up.

take it for a drive and let it sit again -- then check your coolant level and add accordingly. --

HTH

--John

 

You can get a yellow coolant now which is compatible with any other coolant. Since you're going to flush the system, it won't really matter which you use, but "universal" is probably the best choice for the obvious reason of compatibility. Distilled water is cheap, but not required. I'd not bother with a 50/50 premix because you pay more for it(by volume) than 100% coolant.

Going through all this, you may as well get new hoses(unless yours are fairly new now) and the aforementioned T-stat. While you're at it, look over the belt and consider replacing that too, since you've already pulled it for the job. Also, inspect pulleys to be sure they're either spinning appropriately, or not spinning(crank) and don't forget to examine the harmonic balancer since you'll have a better view of it, making sure the rubber is in place.. Since you're replacing the chain, get the 3-piece kit.

You may also wanna remove the radiator altogether to add room for working in there. If you wanna free up some power and still have the stock fan set up, you could go to electric fans too, but that will add a couple bills(for good fans) to the cost of your already $150-300 dollar job(depending on parts choice and of course, your local market).

Oh yeah, and if you go to the drag strip and race this car, remember that NO anti-freeze/coolant is allowed at most tracks. You'll wanna look into Water Wetter or something like it.

 

If your going to flush the system next week and change the gaskets. Then just add water until you do it. No reason to waste money on Coolant and then having to rebuy it again.