I very seldom drive my ///M3 these days, preferring instead to let my E39 528i Touring handle daily driver duties. I've put less than 6K miles on it in the last two years. But I had to visit a client in Tallahassee, FL which is about a 300 mile round trip for me. The weather was nice and I wanted to blow the cobwebs out of the ///M, so it took the trip with me. The drive down was swift, but uneventful. I parked in the lot of a bar where I was meeting my client and went inside. About an hour later I came back out to get my laptop and saw this:

Not something you want to see when 150 miles from home. An inspection found a split in the upper radiator hose right next to the thermostat housing. I guess if you are going to have a coolant leak far from home, that's the one you'd want - it was easy to find and is the easiest to repair. I called around and found an Advance Auto Parts that had a hose in stock, borrowed my client's truck, and got the hose. In an amazing coincidence of luck, I had a full bottle of BMW coolant with me, so I set about replacing the hose in the parking lot later that night.

I did a complete cooling system overhaul on this car at 89K miles and am now at 130K. I have flushed the coolant twice since then, too. It seems to me that the hose should've lasted longer than 41K miles. I used all OEM parts for the overhaul, so I am quite disappointed. The hose I bought from Advance was made in the US of A (not China), so hopefully it will be at least as good as the OEM hose it replaced. FWIW, this car is on it's 4th water pump, too!

The ride home was again swift and uneventful. However, the next morning there was another coolant puddle on the garage floor. It looked like it was coming from where the upper hose attaches to the radiator. I've had good luck with using high temp RTV silicone to seal that hose, so I pulled it off to seal it. This was Sunday morning, by the way. While I had the hose off, I noticed that the oil filter housing gasket was beginning to leak. I had an extra one on hand and figured it would be a good time to deal with that, too.

With the alternator removed, I had good access to the power steering plumbing which has been leaking for a long time. I have been collecting the parts to replace all the power steering hoses, so it seemed like a good time to go ahead replace them.

Another issue I've been putting off dealing with is that the hex bolt in the serpentine belt tensioner is stripped out making it nearly impossible to loosen the belt for removal. I finally managed to loosen it just enough to get the belt off and then removed the entire tensioner assembly to try to replace the bolt. That sucker was tight! I could not get it out even after soaking it for 24 hours with PB Blaster and heating it with a torch. I had an extra mounting bracket, but the pulley on that one was very rough. I replaced the pulley on mine when I did the cooling overhaul and wanted to keep using the newer pulley. So, I busted out the Dremel and cut the bolt out - which took over an hour. But I got it out and transferred the pulley to the other bracket and installed a new bolt.

Since I had the engine bay taken apart, it made sense to rebuild the VANOS (rattle repair and new seals) since I have also been collecting all the parts and tools for that job. Of course, the valve cover has to come off, so even though I have already replaced the valve cover gasket, I put a new one back on. With the valve cover already off, there will never be an easier time to replace the primary and secondary timing chain tensioners. And since I happened to have them in my parts cabinet, on they went.

In order to gain access to the bolts on the exhaust cam the cooling shroud must be removed along with the overflow tank. I have been getting erroneous "Low Coolant Level" warnings on the Check Control for over a year (even though the coolant level is correct) and had a new coolant level sensor. So I replaced that while I had the tank removed.

I started work at about 9:00 Sunday morning and worked until about 10:30 that night. Worked on it after work on Monday, Tuesday, and Wednesday nights. I finally buttoned it up and did a coolant bleed at about 9:00 Wednesday night.

I drove it to work this morning and so far, all of the coolant is still contained. Time will tell if it stays that way.

I did notice an improvement in the VANOS. The rattle was gone when I bled the coolant and it seems to pull a little stronger in the lower gears. But I am taking it easy for about 100 miles to break in the new VANOS parts and also to not overly stress the engine until I know for sure that the various repairs are going to hold.

I also was surprised by how clean the top of the engine was when I pulled the valve cover off. About 4 oil changes ago I switch to Royal Purple from Red Line (mostly because I can get RP locally instead of having to order RL). I'm not trying to start another oil war, but it looks to me like RP is good stuff. Because it's so dark going in, and positively nasty when drained out, I was expecting all the hardware inside the engine to be stained a very dark shade of purple. But everything was bright and shiny. I actually attribute it more to regular oil changes than the oil itself. I have opened up newer engines with lower mileage and found them full of black crud, while there wasn't a speck in the ///M engine.

Anyway, the job is done (hopefully) and with any luck, it will be a while until any more major work is needed. At least on this car!