Coolant change

[jcaspar1]

It is time to change the coolant in my GTS. The shop manual refers to block drain plugs behind the exaust manafolds which I cannot seem to find. Can anyone offer a description where these are? Thanks

[Bill 96 GTS]

That's a good question. I need to do mine also. The shop manual for 96 doesn't show them. Anybody out there remember?

[Ron]

<FONT face="Comic Sans MS">If you're talking about a GEN II car, I can help. I changed over to Dex-Cool (orange) antifreeze about a month ago (5 years change interval, better heat transfer, longer water pump life) and drained via the radiator and the block. The shop manual mentions a petcock, but my '96 GTS had only a allen keyed plug. That's on the drivers side. Be careful when loosening it as if your not dead straight when you apply force, you'll bend the soft brass tank surrounding the plug. As far as the block drains go, they are up above the oil gallery wall, middle of the engine with the head facing down. There is only one on each side and they are female square keyed plugs. You need some sort of plumbers tool to remove. A 1/2" rachet drive is too big and a 3/8" is too small. Not being a plumber, I bought a short 1/2" extension and ground down the 4 sides until it fit.

Don't forget the air bleed in the thermostat housing (front of the engine.. follow the upper radiator hose back). It's allen keyed also and you can see it through the intake manifold, facing straight up. You'll need to fill your coolant tank with this plug out so the air can bleed out. Also, I used a $2.00 fish tank squeeze bulb siphon to remove the old antifreeze from the inaccessible overflow bottle, refilled with water using a funnel stuck into the hose, drained again, then refilled with the 50:50 mix. You'll have to put a light bulb inside the foglight port in the inner passenger fenderwell to light up the tank so you can see how much fluid to add.

Lastly, don't forget to burp you system by running with the heater on and carefully squeezing the upper radiator hose to get the last of the air out. Once you stop see air bubbling into the coolant tank you should have it covered.

A few other points. I use distilled water for my last flush and to mix with the antifreeze. Hard water might calcify in the system. Antifreeze will destroy your liver rather quickly, so mouth siphoning is a no-no. I transfer the waste into old antifreeze containers (with little kids around, I like the safety caps on these) and drop them off at my local autoparts store for disposal. If you run the car with water to help flush the system, (very important if you switch to Dex-Cool as I did) make sure you let the car heat up to open the thermostat, but then let it cool before draining and refilling. You don't want to crack anything. This makes it a half a day job, but with Dex-Cool you only do it once every 5 years.

Probably more information than you wanted.....</FONT f>

[jcaspar1]

Thanks Ron. Excellent description. I really appreciate it. Should be part of the tech section.

[Ron]

<FONT face="Comic Sans MS">My pleasure. Glad I could help.</FONT f>

[Bill 96 GTS]

Thanks Ron

[Ron]

<FONT face="Comic Sans MS">My own TMR...

Was working on the car today and noticed that the themostat air bleed is actually a female square cut plug, like the block drains, only smaller. I previously remembered it to be allen keyed. You'll find it just behind the PCV valve and in front of the first intake runner. You might have to move a vacuum hose to see it. Also, the engine block drain plugs are right next to the O2 sensors that are tapped into the inside of the exhaust manifolds.</FONT f>