teamcrossworks

1987 944 Turbo - Looking to flush my cooling system and replace my fluid. Any suggestions on what brand and/or ratio to water would give me the best cooling properties?

Thanks!

Tom M'Guinn

Just be sure to use a phosphate-free coolant made for aluminum. Prestone makes several versions. Always use distilled water, rather than tap water, to avoid corrosion issues. Weaker mixtures (i.e., less coolant, more water) tend to run a bit cooler, but also lead to more corrosion (pitting in head, etc.). I've finally come to the conclusion that it's best to run near 50/50 mixture. If your motor needs a weak mixture to run cool, then it's better to fix the cooling system than to run a weak mixture. A bottle of Water Wetter can help a bit too.

m73m95

^^ What he said.

I use phosphate free zyrex (gold colored). Sold at every napa across the country, and I've seen it at a few Auto Zones as well. Mixed 50/50 with distilled water, and a bottle of water wetter.

JohnKoaWood

http://www.paragon-products.com/prod...043.301.05.htm

Same thing the Porsche dealership would use... 1 gallon + 1 gallon of distilled water..done

fortysixandtwo

I'm lazy, so I use the Prestone 50/50 premixed stuff.

m73m95

The only problem I've got with using the "not over the counter" stuff is, if your on a trip and lose a hose, its impossible to find it in the small town you will inevitably be stranded in. (Been there)

Sure you can top your system back off with another brand of stuff to get you home, but then you have to flush the system, and refill with the "special" coolant.

There is a napa in just about every small town (and large towns too) in the US.

If you spring a leak in a hose, you can mend it with some "hose mend" tape, or replace it if they stock it, then refill the system with the same coolant you already have in your car (Zyrex phosphate free).

JohnKoaWood

So did the PO of my 951... I am still chasing corrosion out of the engine bay... heater core is being replaced this winter while the dash is out...

Buy a 2nd gallon, and carry it in the back of the car... I have one in my car right now! Once upon a time I used the Zerex as well.... then I had to replace every metal part on my N/A from Corrosion... I have been using the P-Car coolant, and have NO heat or leaking issues, no hot running temps, just normal operation... I also use the correct GL-12 in my Audi... the OEM engineers didn't make their own coolant just to mess with you.. I firmly believe the correct coolant really does make a difference...

Chris White

Ewwww....

eniac

I use the BMW blue stuff. The Audi G11 coolant is an excellent choice as well.

Any "green" compatble coolant that is phosphate free should be ok to use. Just be certain it says that on the label. I always add water wetter in my car.

JohnKoaWood

WOW..

My old radiator was almost that bad, as was my coolant tube (above the header) , the coolant necks at the front and back of the head... the old water pump was disgusting as was the crap I flushed out of the block and heater core... All 3 coolant sensors were trash .. car ran HOT, now run mid gauge all the time...

regular coolant changes, and proper mixtures are the way to go... both my p-cars had dexcool in them when I got them, and both looked about the same, but the 951 was far worse internally...

Chris.. have you notices any differences with HG condition when removing them on cars running different coolant? That looks like it was running contaminated p-car coolant (pink)... or had never been changed...

NASTY, I bet the rest of motor looked simillar... makes cleaning the block and head a chore doesn't it? Also makes the radiator and heater core almost ineffective!

V2Rocket

FWIW i live in the socal desert and use a generic mix of prestone orange juice and water, lately i started a leak from the heater valve so i have been topping it off every few days with straight water, my temp needle never even gets to the middle mark unless i have the heater on driving uphill.

JohnKoaWood

Just wait untill you hit the boost pipe... your temps will start creaping up, and then throw in gome nasty crud...

OH BTW... Change your friggin valve already!

more water will run cooler, but be less resistant to freeze... racers run straight water as AF isn't allowed on track... it gets slippery...

V2Rocket

im thinking i might put a lower-temp thermostat and low-temp fan switch on my car, also putting a 951 oil cooler (maybe a larger one eventually) will bring the coolant temp down even more


anyways i discovered that the valve isnt the problem; the hose that goes into the firewall from the valve somehow has become somewhat loose from the valve. like i looked at it and the hose clamp came off completely and the hose slipped down to almost the end of the barb. the car is parked at least til this weekend and i might be doing belts this weekend (along with a little experimenting which you will hear about that involves removing my intake..) so ill take care of that then.

Chris White

Thats the way many clutches have died...the valve/hose will leak right down in to the bell housing and screw up the clutch.

mtnman82

+1 Chris: Have you noticed any difference between coolants on the engines you've torn apart?

Hmmm, when I did my belts, h2o pump and oil cooler I had the same stuff Chris posted above. Posted pic's of it too. I must have flushed the system 20 times before I got it clean-'ish' (will probably do it another 20 times when I get a chance again...). I also used the green Prestone that says "phosphor free" on the label, but you guys have me worried now...

I noticed one of the two local small indy import shops had some genuine Mercedes coolant. I wonder if that's good/complatible (one would assume)?