GregMN's 1991 W126 350SDL Has A New Home - Page 3 - PeachParts Mercedes-Benz Forum

Squiggle Dog · #31 09-25-2018, 09:26 PM

Finally, after over two years of working on the 350SDL, it was ready for my roommate to start using it. He was so excited that he stayed home from work, printed out a trip permit, drove it to the emissions station, got it licensed and registered in his name, and got five new tires put on the CLK rims. We cleaned up and treated the rust around the rear fender arches and installed chrome trim to cover it.

He drove it to work the next day and said that it drove like a cloud, but the air conditioning was blowing warm air. He took the car to an air conditioning shop and they charged $65 for an inspection. They quoted him $1,500-$2,000 to get the system to hold refrigerant. This included a new compressor (they said it was bad and wanted $1,000 for a new one), a new manifold hose, and labor. Then after the system would hold refrigerant, they would want another $1,500 or so to fix the "Jerry-rigged fan wiring" and the non-operational dashboard vents, which they said is a common problem.

So it looked like we were going to have to buy the parts and install them myself as these shops mark up the prices so much and charge so much for labor. He ordered a new Denso compressor (under $200) and had the hoses remade with barrier hose for $250. The hose shop also repaired the stripped-out aluminum threads on the stock parallel-flow condenser.

I was advised to flush the evaporator. What I did was drill a hole through the smaller holes of the old expansion valve and blew it out and cleaned it with flush. Then I installed the expansion valve and the hoses. I ran the thick hose through the firewall and fitted a funnel to it, while routing the thin long hose through the cabin and into a gallon water bottle. I poured in some A/C flush from a bottle through the funnel so that it would fill up the evaporator and I let it soak for half an hour. During this time I hung the catch bottle off the turn signal stalk.

After this I moved the catch bottle down onto the ground outside the car with the long, thin hose still attached. I then blew compressed air through the thick hose in the firewall as it drained into the catch bottle.

The flush is a clear liquid. What came out into the bottle was bright orange with not a speck of dirt. I'm not sure if the orange color is from a leak dye or the color of the old oil. I flushed until the fluid came out clear. I then blew compressed air through until nothing was coming out, then disconnected the hoses and then blew compressed air through the evaporator again from inside the car. Then it was left open to dry out for a few days. The old expansion valve was held together with J-B Weld.

The new expansion valve came from the local auto parts store. It was listed as Murray brand, but the stock photo showed an Egelhof made in France. When we looked at the box, the box was labeled Made in China. The valve had a big sticker over the original sticker. So I peeled that sticker off, revealing an Egelhof R-134a sticker underneath. No indication of where it was made, though, but probably China.

He got the air conditioning charged with R-134a, but it was only blowing 48 degrees F out the vents and didn't seem very cold, which was disappointing. So, I stayed up late that night and though I couldn't find a vacuum leak, the vent pods weren't opening and letting any cool air get through the vents; however the floor vents were stuck open with some metal that someone propped in there. I teed the vent pods to the main vacuum source going to the switchover valve and removed the home-made floor vent props.

Now it blows nice and cold and strong through the vents instead of an anemic lukewarm breeze.

vwnate1 · #32 09-25-2018, 10:00 PM

What a great thread .

I wish any of my W123's could get 48* F anywhere in the system .

WVO has destroyed so many good old Diesels, it pisses me off .

I have freinds here and there who are not lazy and do all those steps necessary to make WVO work, they're tight fisted, I have better use for my time ~ working endlessly on old clunkers, of course

.

Keep up the good works, glad you didn't loose an eye on the tranny spring ! .

tyl604 · #33 09-25-2018, 11:43 PM

Agreed. A great thread. And what skills. Congrats.

ROLLGUY · #34 09-26-2018, 09:18 PM

Quote:

Originally Posted by tyl604

Agreed. A great thread. And what skills. Congrats.

X3 for me.
That car is exactly like the 350SDL I had. It is now in Sweden. The original mineral oil is what was flushed out, it turns that color. I have seen it many times.

Squiggle Dog · #35 09-28-2018, 02:02 PM

The 350SDL got the grille adorned with some badges, one of which was a gift from ScooterABC. The windows were tinted with limo tint to help cool down and protect the interior. He also had about $1,000 worth of sound system installed in it so it really thumps.

Due to the age of the brakes, a caliper that was sticking, and loose wheel bearings, I did a brake job. Because of the convenience and low cost, my roommate bought a set of remanufactured calipers by BrakeBest at O'Reilly Auto Parts. His car had Bendix on the front and ATE on the rear, but I like ATE better, so we ordered in ATE calipers front and rear. The calipers that came in actually looked really good.

Unfortunately, we found that the new ceramic pad set he got wouldn't fit between the front calipers and rotors. It turns out they only sell the ceramic pads in 17.5mm thickness and the ATE calipers only fit 15mm pads. Darn. I thought about trying to grind a couple mm off of each pad, but that's a pain to do each time the pads are replaced and then there will be issues if they are not perfectly flat. So, we returned the ATE calipers and ordered in Bendix calipers.

The front right Bendix caliper, pads, and rotor fit together perfectly. Awesome. But, the pistons and heat shields in the front left Bendix caliper looked different than the right side ones--like they were cheaper quality. Odd. I did a test fit and the pads wouldn't fit between it and the rotor. I pressed the pistons in as far as they could go and was able to force fit the pads in, but the rotor would not turn.

It looked like on that front left Bendix caliper, that they rebuilt it with pistons that were too tall so 17.5mm Bendix pads can't be used--you have to use the 15mm ATE ones. The caliper on the left is the one with the pistons that were too tall, while the caliper on the right was correct.

It gets better! The pins provided in the hardware kit were way too long. The pin at bottom was from the left side caliper, and the top one was from the right side caliper.

When fully seated, the clip wasn't even in the bore, so the pins would just fall out. But, the right side caliper that was good had the correct length pins.

I wasn't going to have that, so I ordered in another front left Bendix caliper. The parts store ordered in two of them by accident. BOTH of them were rebuilt with pistons that were too tall AND had pins that were too long. But the good thing I can say about them is that the bleeder screws weren't as puny as the on the previous set.

I was inspecting the Bendix rear calipers, and the hardware set that came with them was really cheap. The spring wires that hold in the pads were bent out of shape and kept catching on the pad shims. One side came with silver pins and gold springs, while the other side came with gold pins and silver springs. One side had a large bleeder screw and the other side had a small one--both different thread pitches. I decided that I didn't like the Bendix rear calipers and returned them for ATE rear calipers since the pad thickness doesn't matter on the rear.

The ATE rear calipers that came in were not the ones I had returned a few days earlier. One of them was missing the hardware kit. So, I ordered in two more rear calipers. One of them was also missing the hardware kit, and the other was a new casting that looked to be of atrocious quality. But, I was able to come up with a decent set of two out of those four--although the rebuilder ground off the "step" that aids in anti-squeal from the end of all the pistons and one of the boots had a hole in it from when the snap ring was installed, though the opposite side caliper boots had no snap rings.

I ordered in another front left and right Bendix caliper in the hopes that the left one would be a good one, and that if not, hopefully the right side would be good so I could pop out the pistons and use them in the left side one. In the meantime, I went to AutoZone and ordered in a set of Bendix front, and ATE rear calipers remanufactured by Duralast to see what they were like. Both the rear calipers were missing the hardware kits and I brought this up. The employee said that if I go onto their website, it will say if they come with hardware or not. I said, "I did, and it said YES, but these are missing it." Not that it mattered as I was content with the ATE rear calipers we had.

But, I inspected the Bendix front calipers and both of them had pistons that were too tall so the pads wouldn't fit, the same cheap-looking heat shields, and both hardware kits had pins that were too long! Unreal! So I had AutoZone refund my credit card. But they only refunded me for three calipers and one core. So, I had to go back and get that corrected. The employee said that I should try Summit Racing.

Then O'Reilly Auto Parts only got in a right front caliper. Same issues of wrong pistons and pins that were too long. They didn't get in another front left caliper and don't know what happened as it was ordered, but they ordered another.

It would take a week for NAPA to get calipers and I would have to pay non-refundable freight if they weren't right. Carquest could only get the front left caliper (which is fine), but they wanted twice as much as everywhere else plus a $40 core charge plus non-refundable freight, and it would be a week out. It would also be Cardone, which is probably the same rebuilder as O'Reilly and Auto Zone.

I stopped at O'Reilly and swapped out the puny front bleeder screws on the front calipers I have with the bigger ones that came on the two left fronts (with wrong pistons and hardware) that they ordered in a few days earlier. So at least I got two decent bleeder screws. I had them order in a pair of ATE fronts. We originally ordered ATEs for the car but they wouldn't work with the 17.5mm brake pads. But, they had the same pistons and heat shields that the one correct Bendix caliper had. So, they were probably rebuilt with Bendix pistons.

I love seeing the auto parts store employees cringe or make snarky comments when they realize the parts are for a Mercedes--because they are voodoo, you know.

I went to O'Reilly Auto Parts to pick up the ATE front calipers. They had Bendix pistons and heat shields in them. The pins in one of the hardware sets were much too long and one of the spring plates looked goofy, even though they both had the same part number printed on the bags. I brought them home, put the air compressor nozzle up to the inlet, and popped out the pistons and heat shields in the front left. I did the same with the front left Bendix caliper and swapped them out. They are interchangeable but different lengths--the Bendix pistons are shorter.

I also was able to come up with two good hardware sets out of the four bags. Now both the Bendix front calipers fit onto the rotors with the pads installed, with almost no drag. Problem solved (for me and my roommate, anyway). Proof that rebuilding of calipers should be left to people familiar with these brake systems because of the high likelihood of getting parts mixed up, that can cause big problems even if the difference is very small. It sure is a good thing that I test fit all the parts before I started painting the calipers and had the car taken apart with plans to get it back together before the weekend was over. Looking back on this, if it was my car, I would have rebuilt the calipers myself.

The Bendix front calipers we used are on bottom. The ATE calipers up top are those from which I swapped out a piston and hardware set.

Squiggle Dog · #36 09-28-2018, 02:42 PM

The rotors were very worn.

I replaced the front wheel bearings and races. It turned out that there were some metal burrs in the front left hub that were preventing the races from seating squarely, and that is where the wheel slop was coming from. I carefully ground the burrs flat and that fixed the problem when the new races went in.

It got new front and rear drilled and slotted rotors, rebuilt calipers (with red caliper paint) and ceramic pads, new ATE hoses, and new Lemforder parking brake shoes.

Before:

After:

Before:

After:

The brakes are now excellent!

jay_bob · #37 09-28-2018, 03:00 PM

Wow that is quite the saga on the brakes. It speaks to the sad state of remanufactured parts these days.

Squiggle Dog · #38 09-28-2018, 03:29 PM

The 350SDL had been smoking badly upon acceleration and was being sluggish. One attempt to remedy this was to remove the EGR valve. The EGR delete kit that I had was one that I bought on eBay or somewhere. It was all stainless steel. I didn't care for the bolt heads sticking up so tall, so I used rounded head bolts. It came with blue silicone water pump sealant (interesting) but I used copper silicone sealant instead.

The stainless steel exhaust manifold plug was very thick and I could not get it to fit. The clamp would not close down enough because the plug was way too thick. The thickness of the metal on that end of the EGR valve was paper-thin, and if you put in metal that's any thicker, the clamp will NOT tighten over it.

So, I took a jar lid that had a 36mm pop-up button that was the same diameter as the plug. It was already the perfect shape and size, so I used a Dremel tool and cut out slightly larger than the button (to 38mm) and used a file to smooth out the edges.

Then I placed the newly made plug against the end of the manifold and tapped on the edges with a hammer so they would bend over the sides. After that, I used copper silicone sealant and the clamp fit right over it. I used brake cleaner to get the expiration date off of the paint.

If the clamp makes the plug buckle at the open end, you'll have to remove the clamp and use a hammer to make sure the edges fit tight against the manifold end. If the end up the plug sticks straight out past the end of the manifold, the clamp will catch it and make it buckle. It has to fit tightly against the manifold first.

Squiggle Dog · #39 09-28-2018, 03:54 PM

The wipers were getting stuck partially during operation and also not parking. The washer fluid also wouldn't squirt unless the headlights were on. I installed a new wiper relay, but that didn't solve the problem. So then I decided to inspect the wiper linkages.

I vacuumed out the leaves and debris and then hosed out the area under the wiper assembly to keep the drains free and the body from rusting. Rusted spots got treated with rust converter.

I cleaned and lubricated the moving parts with synthetic transmission fluid and synthetic graphite grease.

The wiper assembly back in its home.

The covering back in place. It's very interesting how they designed it. The mesh is aluminum which is molded into the plastic covering and the paint on it was coming off, was dented, and had a hole punched in it. So, I removed the dents, flattened out the area where the hole was, then masked and painted the mesh so it looks like new again. The wipers sure work a lot smoother now, though the washer still only works with the headlights on, and the high beam indicator is now stuck on all the time.

Squiggle Dog · #40 09-28-2018, 04:18 PM

We were headed to the GoodGuys swap meet in Scottsdale and while pulling in quickly to the Wells-Fargo Bank along the way, the oil pan smacked the ground since the shock absorbers are worn out and the oil pan sets low anyway. We cringed but didn't think anything of it until we came back to the car after attending GoodGuys and saw a black puddle under the front of the car.

The oil pan was cracked and leaking out oil, but the oil level was still above the MIN line and it seemed it didn't leak when the engine was running, so we drove the car to the auto parts store to buy some oil so it could make the rest of the journey home.

I imagine it's a big job to replace the oil pan and then it would take a while to have a replacement shipped. So, I decided I would try to J-B Weld it. In order for this to have any chance of working, I knew I'd have to drain the oil and get both the inside and outside of the oil pan free of oil and sprayed with brake parts cleaner. I also sanded the outside of the oil pan with coarse sandpaper.

It's been almost a year since I did the repair and it's still holding up, though I think a replacement oil pan should be obtained at some point because I don't forsee this repair lasting permanently. We'll probably want to obtain a pan from a W126 350SDL, but the one on the engine now is from a W124 300D since that's the car out of which the engine came. As you can see, the ASD hose going back to the differential just floats there with nothing against which to secure it.

I think that lowering the car is probably not a good idea.

ROLLGUY · #41 09-28-2018, 04:34 PM

Quote:

Originally Posted by Squiggle Dog

We were headed to the GoodGuys swap meet in Scottsdale and while pulling in quickly to the Wells-Fargo Bank along the way, the oil pan smacked the ground since the shock absorbers are worn out and the oil pan sets low anyway. We cringed but didn't think anything of it until we came back to the car after attending GoodGuys and saw a black puddle under the front of the car.

The oil pan was cracked and leaking out oil, but the oil level was still above the MIN line and it seemed it didn't leak when the engine was running, so we drove the car to the auto parts store to buy some oil so it could make the rest of the journey home.

I imagine it's a big job to replace the oil pan and then it would take a while to have a replacement shipped. So, I decided I would try to J-B Weld it. In order for this to have any chance of working, I knew I'd have to drain the oil and get both the inside and outside of the oil pan free of oil and sprayed with brake parts cleaner. I also sanded the outside of the oil pan with coarse sandpaper.

It's been almost a year since I did the repair and it's still holding up, though I think a replacement oil pan should be obtained at some point because I don't forsee this repair lasting permanently. We'll probably want to obtain a pan from a W126 350SDL, but the one on the engine now is from a W124 300D since that's the car out of which the engine came. As you can see, the ASD hose going back to the differential just floats there with nothing against which to secure it.

I think that lowering the car is probably not a good idea.

I bought my 350SDL with a hole in the pan. I actually got one from a member here that was traveling, and passing through nearby. It was from a 3.0 OM603 ('87 300D). It worked just fine, and was not as big of a deal to replace as I thought it was going to be. There is a thread somewhere here about the job.

Squiggle Dog · #42 09-28-2018, 04:55 PM

The power steering had been failing and it got to the point where it was extremely difficult to turn the steering wheel at low speed, so I decided to rebuild the power steering pump, but it's a dual-chamber tandem pump.

Why is it dual-chamber? Because Mercedes engineers decided to make an Anti-Slip Differential as complicated as possible--instead of just having clutch packs in the differential, they had hydraulic fluid run through the power steering pump (which also pumps power steering fluid that can't mix with it) and through hoses and tubes going back to a valve unit with an accumulator sphere which then locks the rear axle and then the fluid circulates back into a bottle and filter in the engine compartment.

The main valve is controlled by electrical relays also, which receive input from wheel and brake sensors. To bleed air out of the system, you have to remove a relay, bridge some of the pins with wire, then attach a clear hose to a bleeder valve on the differential while the engine is running. Talk about over-engineering.

But, the rebuild kits for the tandem power steering pumps have been backordered for years and may not again come into production. My roommate and I scoured the internet for places to buy one, only to be told that they were out of stock and couldn't get any more. Finally, my roommate found a place that had two, so he bought what are probably the last two rebuild kits in existence. I still ended up having to anneal some copper washers so I could reuse them.

Apparently very few cars were built with the ASD system and it's a very rare option. Rebuilding the original pump was much more realistic than paying $1,478.99 for a rebuilt one. In order to use a standard power steering pump, the entire anti-slip differential system would need to be removed and the rear axle would need to be replaced with a standard type.

Unfortunately, this didn't seem to solve the power steering failure. Maybe the steering box needs to be rebuilt. I removed the ASD relay in an attempt to bypass the ASD system so the hose wouldn't slap up against the oil pan and the rear axle accumulator sphere would stop hissing, but it didn't work.

The ASD light has been on for a while now, so I guess I'll have to run a diagnostic, replace the hose going back (which is heavily worn) and install a new accumulator sphere.

Squiggle Dog · #43 09-28-2018, 05:09 PM

Quote:

Originally Posted by ROLLGUY

I bought my 350SDL with a hole in the pan. I actually got one from a member here that was traveling, and passing through nearby. It was from a 3.0 OM603 ('87 300D). It worked just fine, and was not as big of a deal to replace as I thought it was going to be. There is a thread somewhere here about the job.

That's good to know! The front crank seals needs to be done as well.

vwnate1 · #44 09-28-2018, 08:38 PM

So ;

Did the EGR delete stop the smoking ? .

The brakes look & sounds good, I had the devil of a time getting rebuilt calipers for my 300TD, in the end Pelican sent me a no brand new manufacture caliper that seems to be working O.K. .

I kept my old ones as cores .

The were 'rebuilt' using phenolic pistons ad failed going down a steep grade in the rain.....

.

Squiggle Dog · #45 09-28-2018, 10:03 PM

Quote:

Originally Posted by vwnate1

So ;

Did the EGR delete stop the smoking ? .

The brakes look & sounds good, I had the devil of a time getting rebuilt calipers for my 300TD, in the end Pelican sent me a no brand new manufacture caliper that seems to be working O.K. .

I kept my old ones as cores .

The were 'rebuilt' using phenolic pistons ad failed going down a steep grade in the rain.....

.

I think it helped a little, but there's still an acceleration issue and the exhaust smokes black when you put your foot down to try to go any faster. The throttle response is delayed and it feels like it's dragging a boat anchor behind it, especially when the air conditioning is on.

What's interesting is that my W116 300SD has a lot better acceleration performance and rarely any kind of smoke. This W126 350SDL is supposed to be faster, but it's not, so I don't know if the timing chain is stretched, or if this is normal performance.

It's scary, some of these rebuilt calipers...

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