Coolant on the garage floor
On Saturday I finally took the time to replace the coolant in the 900, and to replace radiator hoses and the thermostat. I decided to give up a beautiful practice day (with my new Azenis RT-615 tires) with BEAC to do that maintenance, though the practice had actually been moved from Saturday to Sunday, but I knew that I didn’t have enough free hours in the weekend to do both and I’ve been needing to do this since I bought the car.
The first order of business was to remove the air conditioning compressor. Or so I thought. Removing the compressor would allow me access to the lower radiator hose where it connects to the engine. Since the A/C system has no refrigerant in it, I figured it’s a logical, weight-saving step to remove the components.
What I found is that I need a very large torx bit at the end of a long-handled ratchet or wrench in order to free the compressor. I didn’t have the torx bit, so I was stuck. I decided to skip that step and go straight to draining the coolant from the car. That is most easily done by removing the drain plug from the bottom right side of the radiator near the battery. Which wasn’t easy. There was no way to get a wrench or pliers down near the drain. And none of my sockets were large enough nor deep enough. It was a tough go with an adjustable pipe wrench to loosen the drain plug. Of course, the drain plug is directly over a frame member, so that the coolant will drain directly down onto the frame member and drip onto the garage floor in several locations, making it impossible to catch all of the drips. I sacrificed half-rolls of shop towels and paper towels to keep the mess from flowing right out the garage door. Only after getting the drain plug all the way out did I discover that I could have put some type of hose on a nipple on the end of the drain plug to direct the coolant into a container rather than letting it drip all over the place.
While that coolant was running out all over the place out of the bottom of the radiator, I worked on freeing the upper radiator hoses. There is one radiator hose from the top left of the radiator to a temperature sensor, and then another from the temperature sensor to the thermostat housing, and a third that is a short elbow that feeds from the head to the heater. I managed to get all of those off while spilling maybe only a quart of coolant all over the side of the engine. Just another opportunity to throw more paper towels on the garage floor.
Next it was time to remove the thermostat housing so I could replace the thermostat. Actually, back up. I had to first unclamp the Idle Control Valve from it’s clamp which is mounted to the thermostat housing, that took just one bolt and one connector, though it still hung out in it’s place due to the two thick vacuum hoses attached to it. After removing that, I found that the thermostat housing is attached to the head by two 12 mm head bolts. I got out my 12 mm socket, pulled on the handle, and the socket broke. The side kind of gave way. That sucked. So I looked through my other socket set, but its 12 mm was missing. I next resorted to the non-metric sized sockets. Knowing that 12 mm is just shy of ½ inch, I eventually found my 15/32 inch socket and it fit nicely on the 12 mm bolt head. I pulled on the wrench handle, and that socket broke too.
Now I was in a lousy position. I wanted to replace the thermostat at the same time as all the rest of this coolant related stuff. I decided that I needed to go and buy replacement sockets for the two I had broken, as well as a deep socket for the radiator plug. Off to Sears in the R I went, thankful that the car I work on is not my only source of transportation. At Sears, I found a 24 mm deep socket for the drain plug, and the replacement 12 mm socket. They don’t carry the 15/32 inch size socket. If I ever need one for some reason, I’ll just have to remember that it’s pretty much interchangeable with 12 mm. I really could stand to rant about stupid “imperial” sized sockets and wrenches, with all of their awkward n/8, n/16, and n/32 inch sizes. I can’t stand it. I’d rather that they were all sized over 32 if any of them are going to be. Reducing the fraction only makes it difficult for metric-heads like me to determine instantly which size is larger between, for example, 11/32 or some n/8. Grr.
Anyhow, once back home with the sockets I had to use my big torque-wrench socket driver to break the thermostat housing bolts free, but I did get them off and replaced the thermostat. I really wish I had paid closer attention to the thermostat when I took it out of the car, so I could know which way the “arrow” was pointing. I think I was able to figure it out, but oddly the book never discussed orientation of the thermostat. It remains to be seen if I’ve properly installed it.
After getting the new thermostat situated, “re-assembly is the reverse of removal”. I replaced the thermostat housing, the three upper hoses, and the radiator drain plug (much easier to do with the new 24 mm socket). Then I mopped up the coolant off of the floor and got it all into containers. The stated capacity of the cooling system is 10 liters, which is about 2.5 gallons for you imperials. I put the used coolant into used plastic milk gallon cartons, and filled one all the way and one half-way. That means there’s still about a gallon (4 liters) that never came out of the car. I opened the bleeder valve and started adding my new coolant and water at a 50/50 mix, and I used approximately the same amount I had mopped up, again confirming that somehow 4 liters remained in the car. I don’t get it. The instructions had stated to slowly pour coolant into the reservoir, so that it could make its way to the bleeder valve; when coolant starts coming out the bleeder then close it and stop filling. Well it came out of the bleeder like crazy before I could get it closed, so I spilled several milliliters down the side of the engine. Typical.
The next step is to start the car and watch for leaks. I did find one at the heater hose elbow. Tightened that up without problem. I thought I was done, with only a road test remaining. Since we had dinner plans with friends and it was late in the day, I decided to clean up. After doing so, I came back down to find that the 900 was peeing coolant onto the floor at a slow drip. We went to dinner and I investigated again on Sunday morning, which was a beautiful day for the re-scheduled autocross practice. The dripping had stopped, or significantly slowed. I’m hoping that it was just dripping off of the engine/frame from the massive amounts of spilled coolant in the draining and bleeding processes. I never had the chance to troubleshoot on Sunday, because we needed to do shopping, then we assembled our cool new bathroom cabinet and went for a long-overdue visit with my Nana (driving right by practice on the way to her house in Everett), where Luisa played piano for the first time.
Wouldn’t you love to see photos of all of this? Well too bad, because I didn’t remember to take any. My colorfully descriptive prose will have to be enough. The Swedish Patient is still sitting in the garage in the same spot, with a little puddle of coolant under his front, sporting the brand new Azenis RT-615s, without even having had a road test since Saturday’s work. Sitting just behind the car is the 2nd set of wheels, which I haven’t even had the opportunity to properly inflate yet, let alone put on the car to see how they look. Time is evidently too scarce to have completed all of my goals yet for the 900. But spring is young. I’ll get to it.
