My Custom 1980 W116 300SD Project Part 2 - Page 10 - PeachParts Mercedes-Benz Forum

Squiggle Dog · #**136** 08-01-2018, 07:15 PM

Going back to the plans I had for designing my own hoses, here's my idea for the low pressure hose; a 180 degree fitting points the hose forward as original, and a clamp secures it to the compressor at the strain relief mounting ear.

Then the hose loops backward into the holder bracket on the inner fender, and both the high and low pressure hoses will get inline R-12 service ports in an easily-accessible placement.

When I was removing unneeded wires from the harness, I got carried away and cut the wire going to the manifold overboost pressure sensor and then decided I needed it, as it helps protect the transmission against the high torque from the diesel engine. I soldered the connector back on and replaced the broken sheathing with some from a spare harness.

The connector snaps into a plastic housing which has a cap that screws down over it.

The wire rerouted and attached to the manifold overboost pressure sensor. The sheathing can get stiff due to engine heat and age, but use of a heat gun will soften it so it can be bent to the desired shape.

Squiggle Dog · #**137** 08-01-2018, 07:16 PM

The wire harness coming through the firewall is finished up after some wires were removed and added. The wire going to the manifold overboost pressure sensor was rerouted to go through the sheathing that used to house the wiring for the auxiliary water pump for the automatic climate control.

The grommet on the firewall that used to hold the vacuum lines to the automatic climate control servo got the holes filled with black 1/4" pull-through plugs ordered from McMaster-Carr, and then the ends were trimmed.

The new reciever drier. It's considered a disposable item because it contains a dessicant bag which absorbs moisture from the air conditioning refrigerant, so I couldn't justify spending $212 for one from Mercedes, so I bought a Behr one for $17. At least it looks nice and the sight glass is facing outward so it can be seen, instead of like the one on my car that points toward the radiator.

The two brass switches on it are genuine Mercedes, though. The upper one was about $30, and the lower one was only $23 and free shipping on eBay (MSRP is $82). I had originally ordered a $10 Taiwanese Behr pressure switch, but the prongs were clocked wrong (6 and 12 o'clock positions) and the wire connectors would have had to be bent at severe angles to fit. The genuine Mercedes switch prongs were clocked perfectly at 3 and 9 o'clock. I don't know if this is a quality control issue or just coincidence. I noticed the genuine switch has a small screw in the center, so I wonder if the clocking can be adjusted, but there was no need.

One of the wires that used to power the power windows was soldered to three other wires at the fuse box, so I rolled back the rubber at the ring terminal, cut off the wire, and rolled the rubber back on.

The previous owner must have thought he was an electronics genius as he hacked up a lot of the wire harness to install a sound system which he removed when he sold me the car. Mice also ate a lot of the wiring, so I've had to replace quite a bit of it.

Up next, I need to replace the cigar lighter wires as they were cut off to power the stereo system. They are connected to the wires for the rear dome light switch and relay, so they have to be replaced as a unit. I'm hoping to be at the point where I can start taping the wire harness soon. I have to drive this car to Utah in two weeks!

funola · #**138** 08-01-2018, 08:55 PM

Sorry to hear you are having all these problems! So you bought 2 kits? One from Rollguy and one from Klima? Which kit supplied you a compressor with a cracked mounting ear? I would install an uncracked compressor as there's lot's of torque on those ears. The cracked mounting ear will fail on you later on requiring replacing the compressor which means r&r the R12 freon.

What is your current estimate of completion, i.e. getting system up and running with cold AC? In retrospect, you would have been better off if you kept the stock system with the original hoses, replace the R4 with a rebuilt unit. That's exactly what I did. It's been 2 summers since I did the work and I am enjoying nice cold AC.

dude99 · #**139** 08-01-2018, 09:16 PM

I seem to remember somewhere in this thread you replaced the transmission after you had bought the car. Was the replacement also from a w116? If it was from a w123 or a w126 then you don't need the torque limiting circuit as the later transmissions can handle all the low end torque without issue.

ROLLGUY · #**140** 08-01-2018, 11:37 PM

Quote:

Originally Posted by Squiggle Dog

The oil cooler line mounting bracket from Klima didn't fit my car.

The ridge in the center of the power steering pump bracket prevents the oil cooler line bracket from fitting flush.

When I tried tightening down the bracket, the ridge caused it to bend.

I put the Klima bracket up against the bracket from ROLLGUY's kit. I had no problem with ROLLGUY's bracket fitting, and you can see that his is cut deeper to clear the ridge. Klima said it's strange and they have never had any complaints about their brackets before, but if I want to cut mine to fit, they'll let me do it without voiding the warranty. Unfortunately, I can't use ROLLGUY's bracket because it's longer than the Klima bracket as his goes underneath the oil cooler lines and the lower corner sticks out further, so it interferes with the way the hoses on a W116 have to route. The Klima bracket mounts on top of the oil cooler lines, so there is more clearance below, which is another reason why I wanted to try the Klima kit.

I had the same issue with the Klima kit that I had with ROLLGUY's kit; the belt provided (11X950 for ROLLGUY's, 13X965 for Klima's) was way too small to fit. Both claim that it is the proper belt size for the OM617 turbo engines, but the W116 version must have a larger crank pulley as the compressor has the recommended 132mm pulley. Klima suggested removing the adjuster bolts from the bracket and trying to fit the belt. Doing that, I was able to just barely squeeze on the belt, and then getting the bolts back in was tricky. Once the belt was fully tensioned, the adjuster had hardly moved at all. So clearly, that wasn't going to work. I found that for my 1980 W116 300SD, a 13X990 belt fit perfectly on ROLLGUY's bracket, and a 13X980 belt fit perfectly on Klima's bracket.

The 13X990 belt that I was using on ROLLGUY's bracket was a bit too large on Klima's bracket, so I went to AutoZone to try a 13X980 belt since I had purchased the other belt from them being as their Duralast belts were made in the USA by Dayco, which I felt was a better option than a Continental, which are now made in China and I couldn't find that size in a genuine Mercedes belt (and even genuine Volvo in 13x992 are no longer available). Well, this time the Duralast belt said made in China on it. At least the belt fit, so I know the proper size. I figured that if I'm going to run a Chinese belt anyway, I'd prefer to have a Continental. But, then I discovered there is a genuine Mercedes belt in a close size (12.5X975 004-997-36-92), so I ordered one to match the power steering and fan belts.

My overall opinion of Klima Design Works' Sanden conversion kit is that they probably make a great product for the W123 and W126, but it seems the W116 version needs work. I got the impression that I was their first customer to install the W116 kit, but they said that they have sold many of these and have never heard a complaint other than some people didn't like the low pressure hose setup. Their bracket is really well-engineered. Then again, just about all the rest of it didn't fit, and those are the parts that made me decide to try it out. But, for a W123 or W126, their kits are probably great.

ROLLGUY's brackets get the job done and I didn't have fitment issues with his other than the belt alignment being 1/4" off, but some spacers and longer bolts fixed that. The oil cooler line support bracket fit well, it's just that it gets in the way of the W116 low pressure hose routing, but not an issue with the W123 or W126.

Sometimes learning can be expensive, but now I know the pros and cons of both brackets and my car is getting closer to have working air conditioning for the first time since I've owned it.

Thank you for your honest evaluation of both kits. I don't think anyone else has tried both, you may be the first. I am a little confused about the belt sizes. Most of the belts I buy/use have numbers like: 15375, 17380 etc. The 15375 is a 15/32 X 37.5", and the 17380 is a 17/32 X 38". It's pretty easy to figure out what size to get if it needs to be longer or shorter. The measurements you are using must be metric. I have had good luck with belts from ********. They have the premium brands, and for less than most auto parts stores. As far as the belt alignment, you have one of the older brackets. The last half of the Gen II bracket got the belt alignment sorted out. Of course the Gen III has no alignment problem either. Since the W116 has the same engine as a W123, the hoses should be able to be routed the same on either one. Both the hoses in my kit go up above, but I suppose one could rout one or both to go below the compressor as you have done. I thought about offering a lower hose routing (high side) for the W123, but have not actually done one that way yet. I am leery about running hoses below, as they are more in the elements and have a greater chance to get damaged. The W116 won't have that problem. Keep up the good work, and thanks again.

Squiggle Dog · #**141** 08-02-2018, 01:22 AM

Quote:

Originally Posted by funola

Sorry to hear you are having all these problems! So you bought 2 kits? One from Rollguy and one from Klima? Which kit supplied you a compressor with a cracked mounting ear? I would install an uncracked compressor as there's lot's of torque on those ears. The cracked mounting ear will fail on you later on requiring replacing the compressor which means r&r the R12 freon.

What is your current estimate of completion, i.e. getting system up and running with cold AC? In retrospect, you would have been better off if you kept the stock system with the original hoses, replace the R4 with a rebuilt unit. That's exactly what I did. It's been 2 summers since I did the work and I am enjoying nice cold AC.

The first Sanden conversion kit I got from a forum member who purchased it from ROLLGUY for his OM617 Toyota swap, but there wasn't enough clearance to mount a compressor in that location. I think mine is one of the early second generation brackets, and there have been improvements since then, like use of heavier gauge metal.

The second kit I purchased was from Klima. I got the compressor new from SO-CAL Speed Shop years ago and it wasn't cracked then. However, when I went to install it in the Klima bracket, I noticed the compressor ear was cracked. How or when it happened, who knows.

I really can't afford to go out and buy another $300 compressor, so I'm just going to see how long this one lasts. I'm already into mega credit card debt because of this project.

I'm hoping to be done with the air conditioning in a week and a half. I've really got to push hard to get this done.

I wouldn't have been happy keeping the stock system. The automatic climate control was insanely convoluted and unreliable. It gave me anxiety just being in the car. Converting to manual climate control will be worth it.

I don't think these old Mercedes had very good air conditioning even when new. What may pass as cold in Germany or New York won't cut it in Arizona heat, especially during this time of year (monsoon season) when it's 115 and 80% humidity.

Squiggle Dog · #**142** 08-02-2018, 01:25 AM

Quote:

Originally Posted by dude99

I seem to remember somewhere in this thread you replaced the transmission after you had bought the car. Was the replacement also from a w116? If it was from a w123 or a w126 then you don't need the torque limiting circuit as the later transmissions can handle all the low end torque without issue.

The transmission I put in the car was from a 1979 W116 300SD, so it's identical to what came out of my car.

vwnate1 · #**143** 08-02-2018, 01:31 AM

Keep up the hard works and good reportage .

I hope your up coming road trip goes well .

Squiggle Dog · #**144** 08-02-2018, 01:51 AM

Quote:

Originally Posted by ROLLGUY

Thank you for your honest evaluation of both kits. I don't think anyone else has tried both, you may be the first. I am a little confused about the belt sizes. Most of the belts I buy/use have numbers like: 15375, 17380 etc. The 15375 is a 15/32 X 37.5", and the 17380 is a 17/32 X 38". It's pretty easy to figure out what size to get if it needs to be longer or shorter. The measurements you are using must be metric. I have had good luck with belts from ********. They have the premium brands, and for less than most auto parts stores. As far as the belt alignment, you have one of the older brackets. The last half of the Gen II bracket got the belt alignment sorted out. Of course the Gen III has no alignment problem either. Since the W116 has the same engine as a W123, the hoses should be able to be routed the same on either one. Both the hoses in my kit go up above, but I suppose one could rout one or both to go below the compressor as you have done. I thought about offering a lower hose routing (high side) for the W123, but have not actually done one that way yet. I am leery about running hoses below, as they are more in the elements and have a greater chance to get damaged. The W116 won't have that problem. Keep up the good work, and thanks again.

For Klima being a business, I am surprised at how few cars I have seen with their kits (there is only one person I could find, and that was back in 2012): Klima's W126 300SD 617 Sanden A/C Conversion Kit . I really like to see how products look installed on peoples' cars. Still, in that link, there aren't any pictures of the system complete with the hose secured to the strain relief bracket. It almost looks like it may have the same issue with the oil cooler lines getting in the way. I would really have expected to see more of their products on peoples' cars on this forum.

I always go by metric measurements when dealing with belts for these cars. I was running a 17390 belt with your bracket, and am now running a 17385 belt with the Klima bracket. The belt they provided was a 17380 and it was way too small.

The problem I have with my low pressure hose is there doesn't seem to be much clearance between the body and the oil cooler lines. There is enough to work with, but not a lot. What compounds this is the power steering return hose location which makes it so that running the hose toward the firewall seems impossible to do without the hoses rubbing. There seem to be a lot of obstructions that aren't present on the W123 and W126. But, running the hose forward and then looping it back seems to solve the clearance issues.

My fittings are due to arrive tomorrow, and I guess I'm going to pull the trigger on a hose crimper because my roommate has three other cars that need air conditioning and he'll probably help pay.

vwnate1 · #**145** 08-02-2018, 01:55 AM

I took the time to fully sort out the strange Klima I / Chrysler Air Temp II HVAC in my 1980 W123CD and it nearly froze me out of the car, I used R12 .

However, that darn evil servo drove me nuts and worried me to death - so much so I gave up and sold the car at a dead loss, I'm sure you're going to love the new Sanden based setup, I'm keen to hear all about it .

In this project you're already beyond ROI so keep up the good works and when you're far from home cruising along in style and comfort, you'll smile, knowing it was all worthwhile .

funola · #**146** 08-02-2018, 09:43 AM

Quote:

Originally Posted by Squiggle Dog

............................ I got the compressor new from SO-CAL Speed Shop years ago and it wasn't cracked then. However, when I went to install it in the Klima bracket, I noticed the compressor ear was cracked. How or when it happened, who knows.

I really can't afford to go out and buy another $300 compressor, so I'm just going to see how long this one lasts. .................................

I believe the SD compressors has 4 mounting ears which can be re-clocked so the cracked mounting ear will not be used. I highly recommend doing that.

ROLLGUY · #**147** 08-02-2018, 10:54 AM

Quote:

Originally Posted by funola

I believe the SD compressors has 4 mounting ears which can be re-clocked so the cracked mounting ear will not be used. I highly recommend doing that.

It can only be 90* CW or CCW. That may limit the positions that allow the compressor to mount properly. My bracket needs six of the ears (eight total ears on each compressor), I don't know how many Klima needs. Only two of the ears are most important (mounting to the bracket), the "banana brackets" will still hold with a broken ear, as long as washers are used.

Squiggle Dog · #**148** 08-02-2018, 11:41 AM

Quote:

Originally Posted by vwnate1

I took the time to fully sort out the strange Klima I / Chrysler Air Temp II HVAC in my 1980 W123CD and it nearly froze me out of the car, I used R12 .

However, that darn evil servo drove me nuts and worried me to death - so much so I gave up and sold the car at a dead loss, I'm sure you're going to love the new Sanden based setup, I'm keen to hear all about it .

In this project you're already beyond ROI so keep up the good works and when you're far from home cruising along in style and comfort, you'll smile, knowing it was all worthwhile .

What's nice is now there are companies that sell simplified replacements for the servo and it makes for a more manageable system. Still, all the tubes and wires and switches... it was incredible how many parts got permanently removed when switching to manual climate control.

I like the fact that the Sanden will draw less horsepower from the engine. I've never had a compressor running on my car, so I don't know how much it effects fuel economy and performance, but the Sanden should be better in those regards and last longer than an R4.

Quote:

Originally Posted by funola

I believe the SD compressors has 4 mounting ears which can be re-clocked so the cracked mounting ear will not be used. I highly recommend doing that.

If I clock the compressor differently, if will affect the position of the ports on back. I checked to see if the head can be reclocked, and it looked like it could if it were not for the two alignment pins. Klima recommends using a KG head. I have a K head. The difference is that the KG head is clocked 90 degrees so the fill plug and wire end up being on the side of the compressor instead of on the top. Maybe this makes accessing the fill plug easier, but it seems about 50/50.

Quote:

Originally Posted by ROLLGUY

It can only be 90* CW or CCW. That may limit the positions that allow the compressor to mount properly. My bracket needs six of the ears (eight total ears on each compressor), I don't know how many Klima needs. Only two of the ears are most important (mounting to the bracket), the "banana brackets" will still hold with a broken ear, as long as washers are used.

The Klima bracket also uses six of the ears, the only difference is they use four ears on top and two on bottom, while yours uses two on top and four on bottom.

ROLLGUY · #**149** 08-02-2018, 12:03 PM

Quote:

Originally Posted by Squiggle Dog

What's nice is now there are companies that sell simplified replacements for the servo and it makes for a more manageable system. Still, all the tubes and wires and switches... it was incredible how many parts got permanently removed when switching to manual climate control.

I like the fact that the Sanden will draw less horsepower from the engine. I've never had a compressor running on my car, so I don't know how much it effects fuel economy and performance, but the Sanden should be better in those regards and last longer than an R4.

If I clock the compressor differently, if will affect the position of the ports on back. I checked to see if the head can be reclocked, and it looked like it could if it were not for the two alignment pins. Klima recommends using a KG head. I have a K head. The difference is that the KG head is clocked 90 degrees so the fill plug and wire end up being on the side of the compressor instead of on the top. Maybe this makes accessing the fill plug easier, but it seems about 50/50.

The Klima bracket also uses six of the ears, the only difference is they use four ears on top and two on bottom, while yours uses two on top and four on bottom.

Is the broken ear on your compressor in one of the critical mounting positions? I don't think the heads are re-clockable (is that a word?). At least the 7 cyl are not.

EDIT: The K head is for the 5 cyl, the KG head is for the 7.

vwnate1 · #**150** 08-02-2018, 07:19 PM

? Might it be possible to use a large flat washer on the far side of the cracked eat to gusset it and prevent the crack from spreading ? .