I had been starting to notice exhaust smoke on acceleration that wasn't there before, and there was a lot of oil leaking down from the turbo and manifolds. I can't stand leaks. I had just quit my job, so now with free time finally available, I decided to rebuild the spare turbo--which would minimize the downtime. It would also be a great opportunity to get rid of the EGR valve manifolds that were installed on California emissions 300SDs.
I bought one of Kent Bergsma's High Performance Overhaul Kits that included a new turbine shaft and wheel. Rebuilding a turbo is pretty intuitive, but I'm glad I had the instructions for guidance. Looking back on it, it's probably wiser to send your turbo in to a shop to be rebuilt as it won't cost much more, you might get genuine Garrett parts, any worn bushings will be replaced, and the unit will be balanced and given a warranty. In any event, I've been driving the car for about 6 months and all seems to be well with the turbo. The metal gasket in the wastegate was torn. I had a HECK of a time finding a new one, but it is Garrett part number 409262-0000 Actuator Gasket. I ordered one from Superior Turbo (look them or the part number up on an internet search).
I cleaned the side of the engine and painted the block with rust converter. I sprayed some paint just above the manifold gasket area. I also took this opportunity to install a block heater. I almost didn't do it, though, because I don't really have the money and figured it would take about a week before one would arrive. EBay had some good deals, as did some online parts stores. It seemed I had two choices: genuine Mercedes-Benz which was about $200 (and was made in Canada) or a Zerostart (love the name), which was a lot cheaper and also made in Canada (maybe they make the genuine Mercedes ones?).
The Zerostart appeared to be very high quality and I chose it over genuine Mercedes-Benz, not just for the price, but because it was only a one-piece unit and had a nicer power cord arrangement with a cap to cover the prongs.
I looked up block heaters on O'Reilly Auto Parts' website just for fun and they had one of the Zerostart block heaters at their warehouse for only $60. So I had them order one in and had it the next day. The part number is 310-0105 or Q6200009 and fits 38mm plug threads. It looks like Pelican Parts has genuine Mercedes-Benz ones for only $39!
Mercedes-Benz Block Heatr Kit Q6200009 - Pelican Parts They also have the Zerostart heater:
Engine Heater 9002034895 - Zerostart - 900-203-48-95 | Pelican Parts .
To remove the plug, I bought a Husky hex key socket set from The Home Depot for $25. It came with the proper 19mm hex key and also had a 3/4" key which is the same size if the first were to break. O'Reilly Auto Parts had a smaller set for $20 with only the 19mm key, so that was an option.
I tapped on the plug (not the block) with a sledge hammer and then I put the 19mm hex key socket on a 36" breaker bar with a 24" pipe slid over the end, gave it some force, then pulled it back toward me, and then back the other way. It didn't budge.
So, then I tapped the plug with a hammer again, then put a MAPP gas torch on the plug for about 10 seconds. I put the socket back in the plug, pulled the breaker bar toward me, and then pushed it away and jarred against the bar a few times (which was bowing quite a bit). I finally heard a SNAP! and then I was able to turn the plug a bit. So, I drained the coolant from the block, then loosened the plug while rocking it back and forth a bit to clear up the threads.
The new block heater came with an aluminum crush washer. The plug that came out of the block had no apparent sealing ring. I installed the block heater with the aluminum crush washer and a little bit of anti seize compound on the threads.
The block heater takes a 46mm socket to install. They can be ordered in at auto parts stores but are usually at least $30 each. I was at Harbor Freight with my roommate and they had a 20 piece jumbo SAE socket set (of the highest quality ) for $130 on sale for $60. He had a coupon and ended up getting it for $47, so he let me use the 1 13/16 socket which fit perfectly. There were no torque specs, so I tightened it using the breaker bar and my judgment.
The power cord can attach 180 degrees in either direction. I ultimately had the cord point toward the firewall and routed it with the battery cables under the heat shield toward the front of the car, coiled up the excess length and tied it with a strap, then routed it out under the right headlight and behind the bumper so it can be plugged in without opening the hood (which let's assume would be frozen shut and covered in a foot of snow if I ever get to use it).
I soaked the cast iron manifold and turbo housing in Savogran Wood Bleach (oxalic acid) to remove the rust. Then I painted them with cast iron paint. I used biodiesel and oven cleaner on the aluminum manifold and parts, followed up by Blue Magic Metal Polish and a wire brush.
I am really liking the non-EGR manifolds. I also bought one of Uncle Kent's boost gauges to check the boost pressure. When I adjusted the wastegate as for as it would go, it only puts out 12psi of boost before opening, but that's still better than the stock setting of 7psi. You'll notice that my air cleaner mounts are still ripping despite my engine idling smoothly, valves being in adjustment, and recent replacement of the engine mounts and shocks with genuine Mercedes ones.
