When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Have finally completed my coolant drain, flush and refill. I've replayed below the steps I took and tools used with a few images I hope others will find useful. I followed the 968 workshop and service manuals plus other forum posts.
I managed to complete the whole job without the car on stands or wheels off. However, if you have a lift then this would be much easier than lying around on the garage floor!
Tools used:
- Short cross head screwdriver (for the tapping screws fixing the front undertray to the bumper underside).
- 10mm hex socket and ratchet (for the 6mm set screws attaching the rear end of the front undertray to the adjacent undertray and under body).
- 10mm open-ended spanners (for the 6mm set screws and nuts attaching the undtertray sides to the front fender/wing).
- 13mm open-ended spanner (for the radiator plastic drain plug).
- 12mm ring spanner (for the top bleeder screw on the coolant manifold).
- Flat screwdriver or 7mm socket (for water hose clamp).
First off were the 16 tapping screws along the front and side of the undertray (remove the rubber grommet each end of the undertray to access one other screw). Next off the 3 setscrews/bolts rear of undertray followed by the single setscrew/bolt and nut holding each end the undertray side flange to the front wing. Rusting screws needed some prior WD40 before shifting. I also cut the cable tie holding some lower cabling near the radiator drain plug - more spanner room.
Engine warmed up to normal temp with heater temp dial on hot. Large catch trays under the front ready for water that will travel along the underside radiator bracket support. After the engine had cooled some then protective gloves on and drain plug removed slowly. I did make up a plastic shield to help direct the spouting water down into the catch tray.
Coolant expansion tank cap removed slowly and carefully. Then when draining water was down to a minimum I disconnected the coolant hose from the auxiliary plastic flange of the water pump.
Coolant all drained and now to refill. Reverse of the above (apart from the undertray). Then cracked open the bleeder screw atop the coolant manifold [image below].
WARNING - I snapped the drain plug when tightening up! Maybe over time it had become brittle but it snapped pretty easily and the threaded stud was left in the radiator. Ordered two new replacements and used a braddle with 90 degree bend to work out the snapped plastic stud which was not difficult (a bent nail pin would work too). I was very careful not to overtighten the new plug and only tightened enough that the o ring on the plug was fully in and only tightened as far as the washer plus a gentle quarter turn. The tightening torque for the plug is stated at 4ftlb, which is nothing and not even an increment on any of the small torque wrenches I have!
I refilled with plain soft water (no coolant/anti-freeze) - I wanted to fully flush through all old coolant. Do not fill expansion tank up to max mark (avoids over expansion on warm up) - only half fill tank and until water flows from bleeder screw then loosely close the bleeder screw.
Warm up engine until radiator fan comes on then off. Keep an eye on bleeder screw and when warmed up open bleeder screw further until no more bubbles escape then tighten. The bleeder screw aluminium washer may be worn or past its best but it will/should seal - do not overtighten.
ALERT - Before starting the engine ensure the coolant hose that was disconnected from the plastic flange is mounted back in its hose clip/support further along its length and has not been dislodged to overhang the radiator fan shroud - the fan will when on will cut into the hose!
I repeated the drain steps above once the engine had cooled a bit. The flushed water still showed evidence of previous (pink) coolant and was cloudy. I performed a second water-only refill, warm up and drain. This time the flushed water was much clearer with no sign of previous coolant.
I decided to go for a water/coolant mix that gives @ -25oC protection (despite being in UK and garaged every night). I used 3 litres of Comma Xstream G48 mixed in with nearly 5 litres of de-ionised water.
Nice long spirited hard drive to achieve max water temps where possible. All good, no leaks from anywhere. Once cooled down I topped up to the expansion tank max mark.
Undertray back on having replaced rusted screws/bolts etc and used copper grease on all threads - ready for next coolant change.
Interesting idea - I'd never heard of anyone doing that. Do you drain the coolant from the radiator first, and then use the wet vac to pull out what's left in the engine, or do you use the wet vac for the whole thing?
Pretty much the whole thing. I vacuum out the coolant tank with the bleeder open and then pull the upper hose and go at that. Gets the wet vac nice and clean.
I am lazy. I lift the passenger side and let the coolant trickle down the ridge in the batwing overnight into a pan. zero mess with the drain valve opened a couple turns.
Just reviving this thread as I have been replacing the coolant in my car and run into a little problem. I removed the blue plastic drain plug from the radiator during the process, but when I installed the plug again I broke it like LM964 in his post. When I tried to remove the remaining bit from the radiator hole I ended up pushing it inside the radiator and its impossible to get out again.
So my question is, will the remaining bit of the plug do any harm at the bottom of the radiator if I just install a new plug and refill with coolant, or do I need to install a new radiator.?
Good question too. As it's a tight cooling matrix in the rad then in theory you might get away with it (it won't/shouldn't move around much). However, it may reduce coolant flow, purely as an obstacal. Is it actuall all the in and through the other side of the threaded hole?
Porsche Reveals Coupe Variant of the Electric Cayenne With a Fresh Look
Slideshow: Porsche's latest electric Cayenne Coupe blends dramatic styling with supercar acceleration, turning the brand's midsize SUV into a 1,139-horsepower flagship.
One-Off Porsche 911 S/T Takes Inspiration From Famous '70s Race Car
Slideshow: A one-off Porsche 911 S/T created through the Sonderwunsch program pays tribute to a little-known 1970s race car from the Camel GT Challenge.
Coolant drain? Where?
