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new to SL ownership, few quick questions

5K views 41 replies 14 participants last post by  PanzerPuff 
#1 ·
Hello all!

New to the forum and Mercedes ownership. Although I started with German (VW), Swedish (Volvo) then I drifted to British cars (Land Rover), but now I am ready for some German Challenge.

Plenty SL's about, but I took a few months to follow the market and after reading all your excellent advise here on Benzworld decided the more challenging road: 1983 380SL with full service history, one owner, no rust at all, flawless interior, 83k documented miles - but here it comes: not been moved since 2004 and the seller has been trying to get it running to sell it - but did not succeed. Engine idles nicely but won't rev. Priced accordingly obviously.

Before buying I did scope the timing chain and it is double so sorted there. Engine is super clean inside. AC compressor kicks in but no cold air. All electrics apart from fuel gauge function (this is a hint!) It moves in all gears, but sputters.

Trailered it home and started digging in: Fuel pump setup is complete mess with oozing rubber hose bodged together recently - most likely by PO mechanic. Fuel pump looks new but is surging and howling. Fuel filler neck is a rusty mess. Proceeded to removed the whole rear fuel system and tank is total rusty mess but the tank filter/strainer is intact (and clogged). I think the mechanic tried to removed the tank strainer but could not get it out and then budged the hose with a copper pipe and some other hose - anyway it was dripping fuel..

Tank out now and turns out the filler neck pipe is cracked so I ordered a good used one ($700) and all the bits to restore the fuel delivery including new pump, filter all the hoses and the rest. Oh yeah the fuel sensor was rusted to bits, but my replacement tank comes with one fitted - hopefully all good. Maybe will arrive this weekend.

Given the symptoms I hope the fuel system on the engine is not full of varnish and crud - well we will see...

Ok that was the current status, now for the quick questions:

1. What would be the best fuel additive to clean the system. I was thinking to push a high dose on at startup.

2. While under there I noticed that rear torsion/stabilizer bar was loose. Seems that on both sides the links are disconnected. They are not expensive and I ordered new. Have not taken the wheels of but is this a common failure - I mean both sides? I can hinge the torsion bar up and down by hand...

3. The rear end looks a little saggy, is it common to renew the springs or is this just the car's stance?

4. Since the AC compressor kicks in, can I assume that the monovalve is a likely reason for my lacking AC? The AC operation is rather mysterious. Not very often I need to read an operating manual. Best source for the Monovalve repair parts?

5. I will do all the fluids and have been reading up on most, but the I am not that familiar with the AFT types. Is there a preference?

Thanks so far, I will be reporting back my progress and with more experience look forward to contributing to the discussion!
 

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#2 ·
The AC problem is likely a result of no gas after sitting for so long. I think checking for leaks before paying out for a re gas would be advisable. You have a different set up to mine (old levers on RHD) but I think the monovalve only affects air by pumping out heat constantly if it's kaput. Visual inspection of the rubber innards will tell you whether it's perished. You can buy a repair kit.
I'm surprised that your rear suspension would be no good after such low mileage. My 107 is still firm at 100,000 miles. Good luck.

OH , welcome to the forum mate.

PS love the color!
 
#3 ·
welcome aboard

from what i see of the photo on the trailer, she doesn't look that bad, stance-wise. Highly unlikely the springs have had it at 83,000.

as you are in the Lone Star State, you should be able to get your hands on Techron at Walmart and the like. You chaps over the pond swear by its viagra-like qualities regarding fuel systems. We can get it over here if we look hard, but I have usually used Redex, or recently, 2-stroke oil if I've wanted to degunge. Thankfully, I've never had to degunge like you have to degunge.

I'm pretty sure the ATF is the Dexron II variety, but a quick search on here will reveal all to you. My local car store now sells a magic 'universal' type, so I am slowly replacing my reserves with that when I do gearbox services.

While you are messing with the rear ARB, have a good look at all the bushes you can see in the subframes/control arms etc. I'm only saying this as my front subframe mounting bushes were on their way out, and I ended up biting the bullet and replacing nearly all the others as well. Age and mileage the culprit with mine, but maybe just age with yours. They won't grumble if you give them a squirt of Teflon lubricant while you are inspecting.

Good luck, keep us posted.
 
#4 ·
Congratulations! You chose well.

My car sat with half a tank for almost six years with very little running. The tank itself was okay but nothing else was. I ran a bottle of Techron with every tankful for six months before it cleaned itself up. So be patient. You will also need to free up your breather system or bad things will happen.

The links in your rear suspension commonly disintegrate. They hide behind the wheel and get all the crud and who notices? All I had were the end-connectors, the whole rest just was not there at all.

Good luck!
 
#5 ·
Thanks

Excellent thanks for the feedback. I have order a bunch of Techron bottle and will be running that through. I will just change the suspension links and see how long they last. Need to take the wheels off and have a look at those brakes (which are working, but still). Also the tires seem to be 20 years old so they will be changed with Michelin.

I ordered the bits from AutohausAZ, pretty punctual so far and reasonable cost. Back in Land Rover world parts were cheap, but often of (very) poor quality. Hopefully in Mercedes world things have not degraded to that point yet.

Will report back when I get the bits fitted over the weekend.
 
#9 ·
I really do wonder how the stuff continues to be made. To dupe one "customer" one time into buying $30 weather seals?? What kind of business model is that? Just create a decent aftermarket product and we would continue to buy non critical parts/components I'm sure... Not like the SL and SLC are obscure cars or something either
 
#10 ·
Update

Hi All,

So quick update (been on a business trip, but had last Sunday to work on the car):

New (old) tank arrived and was pleased to see it was in fact rust free as the Ebay seller had stated. The fuel lever sensor was also in working order (my org was in bits). I connected it up to test and found the gauge works, but the fuel light was acting abit funny (less bright and full bright). Anyway I can access and fix that later. So I moved forward installing tank with new (Mercedes) tank screen, all new hoses, pump and filter. The pressure compensator looked good as I could pull a steady vacuum on the small pipe (meaning membrane is intact).

Added fresh fuel and a bottle of techron. Took a bit of cranking to draw the fuel in, but she fired and idled with the pump all nice and humming. No fuel leaks or smells so I think I can see the back end is sorted.

Although the car idles it does not really want to rev much at all. I took of the air filter housing and noticed that the air flow meter was not opening much at all. So with the engine off I 'massaged it' by pushing is down a few times manually. It went down smoothly, but still surprised with the pressure required. I had a Volvo once with the same system and I recall it being a bit lighter (and much smaller). It did seem to move smoother after a few push downs. I fired up the car again and it was more willing.

Took it out for a drive around the block and it kinda interesting with a vvveeerrryyy long delay for the engine to pick up and then for the car to surge forward.

Lots of rattling at the back as well so I changed those stabilizer links which had just fallen apart and properly hung the exhaust for which I had bought the parts as well.

Another drive and things seem to improve enough to take it a little further out. As the light turns green and a very slow departure it comfortably picks up speed and happily runs 40-60 mph. Good oil pressure and steady temperature. Tranny feels good and no undue suspension knocks.

At home I had a good look at all the vacuum lines and all looks to be in order. I cleaned the Idle Air Valve, but this did not make much of a difference. Plugs look new but leads look old, but no signs of deterioration. Distr cap and rotor are new, mech advance is free and there no sign of anybody having adjusted the timing (need to get my timing gun out and check). There is vacuum on the advance at idle (so no leak there).

I am going to change the tires (which are 30 years old) and then use it for a few days to see if it is just varnish holding back the fuel distribution and hope things improve.

Regards,

Jorn
 
#11 ·
This is good news, thank you for sharing your progress. Your mention of the sticky air flow plate made me wonder, have you done the poor man's tune-up yet? This is all the stuff you can do for under $20 each:

1- Spray throttle body cleaner or gumout into the air intake and air flow plate.
2- Techron (yes you did that) with fresh high octane fuel.
3- Change all fluids: oil, brake, coolant, transmission, power steering.
4- the poor man's brake job consists of using a turkey baster or similar siphon to remove as much old brake fluid as possible from the reservoir and then topping it off with fresh fluid; drive and repeat until the fluid is translucent. You can bleed later when it strikes your fancy.
5- Since you are pulling the tires, spray brake parts cleaner on the brakes until it runs clear.
6- Pop the grease caps and regrease the wheel bearings if they look dry.
7- Spray silicone on the bushings, anything that moves made of rubber.
8- Change all the filters: oil, tranny, PS, air, fuel (although this may cross the $20 criterion).
9- WD-40 the seat rails, door hinges, softtop release cables, trunk and bonnet release.
10- Armor-all inside vinyl (this just makes it look better).
11- Spray tire shine on your new tires and do all the black parts of the bumpers at the same time.
12- other stuff anyone cares to mention...
 
#12 ·
I stopped using Armour All a few years back because I didn't like the finish. I recently started using 303 which I got in a gallon can. 303 is loaded with UV protectant, essential for your dash. I also prefer the finish. I have to say though it smells and feels almost identical to the Meguires product. I don't use WD either... I sprayed a crap load of it into a tool box once expecting it to protect my tools to some degree When I next looked they were already rusting. I am not talking months either. Seems there isn't much to it once the carrier has evaporated. Almost anything is as good or better than WD.

For polish I use AutoGlym. It's so easy to use and gives an excellent finish.

Rislone Gas treatments seemed to help me clear my system out. Used it twice in quick succession and the idle has smoothed out some.
 
#13 ·
A little more progress

Changed to oil yesterday. Old oil was not in too bad a state, but possibly 10 years old. Put in 20W50 Gastrol GTX. It does take a fair bit of oil! two large jars, but all nice and clean now. Good news was that the old oil filter was an original Mercedes part. I replaced with Mahle. Refreshing to be able to remove the filter housing without spill with it being vertical and fitted from below.

It still reluctant to rev properly but starts easily hot or cold.

I ordered new tires yesterday morning (Michelin Defender) and they came in the same day. Tonight I plan to have the tires changed and then I can take it for a little longer spin, hoping this will free up the suspected varnish residues in the fuel distribution, rather than it being something more drastic.

Ordered cooling fluid and I noticed when I was underneath there the transmission shifter connector rod was entirely without bushings with the connector rod all loose, so I got two new bushings coming to fix that.
 
#14 ·
Ordered cooling fluid and I noticed when I was underneath there the transmission shifter connector rod was entirely without bushings with the connector rod all loose, so I got two new bushings coming to fix that.
progress! The front bushing is easy if you remove the shifter arm from the transmission and just press the bushing in on the bench. The other one at the linkage is a bitch, either requiring the special tool (search) or shaving the bushing with a razor or cutter just enough so it can be pressed in with your existing tools. I did the latter and the shift is priceless... or the price is shitlist?
 
#15 ·
Further progress made.

Moving on with a full set of tires fitted (Michelin Defender) $500 fitted and will fill in the $70 rebate. So in theory $430, not bad. Guys at the tire bay were very amused with the old tires which they said were dated 1989!! At least that confirms the elderly one owner story and being parked up in a garage for 10 years.

Bit more confident now so took it up to a bit more speed. 70 MPH, easy nice and smooth cruizing. Noticed the brakes are pulling a bit (plan to have the disks skimmed and fitting new pads) and the steering has a bit of play. I also noticed some drops on the steering box, so will do a full inspection of the linkage etc and maybe I just need to adjust the steering box. I can live with a few drops for now, power steering reservoir is full.

Off the line departure is still a bit of a challenge but I can see some improvement so hopefully the techron is doing it's work removing the varnish. I have bought a set of plugs and a new lead set ($$) so that will complete the ignition overhaul.

Tires, fuel system, tank, etc I probably spent about $1500 on the resurrection so far. I would like to stay under $2000, leaving some money for nice to haves like putting in a the rear seats and stuff.
 
#16 · (Edited)
1- If you have a Timing Light, check for 0TDC with vacuum hose to distributor plugged.
Made a world of difference in performance with my 1983 380SL. Timing was way off
on my 380SL - 12BTDC. The shop that replaced my Water Pump F-ed up. It would
stumble on acceleration especially when cold, and performance was poor.

2- Loosey goosey steering - highly suspect you need to replace the Steering Coupler.
On drivers side, remove the Exhaust Shield (x2 8mm bolts I think) so you can
get a good look at the Steering Coupler. Then have someone inside slightly turn
the Steering Wheel back and forth. Bad coupler is when the rubber has deteriorated
to the point that both shafts don't move together causing steering slop.
 
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#17 ·
Hi Carl, thanks yes I have a timing light and will for sure check that out to make sure the while spark side is working as it should. So far I have relied on the fact that the distributor seems to have never been rotated, but obviously the timing could have wondered as some wear occurs.

Thanks for the coupling hint I did not know this is a common concern, but having done a quick search on the forum I can see now this might be the likely culprit. I will inspect and although there seems to be a fair bit of effort involved in changing it out, at least it is always good to fine the problem so you can start fixing.

With the car having covered 80k miles, it seems rubbers and plastics are the only (and predicable) faults so far!
 
#18 ·
There are 3 procedures to replacing that steering coupler.
Ken (Panzerpuff) came up with an easiest way.
I did it by pulling the Instrument Cluster, pulling out the Steering Shaft,
and some other interior disassembly -- I don't recommend this way.

Ken suggests to just loosen the bolts to the Steering Gear Box to allow removal
of the Coupler - no interior disassembly. I think he has a video showing how.

TIP: For Allen Head bolts on the Steering Coupler and the Distributor hold down,
carefully clean the head and make sure you have the Allen Wrench properly seated.
These bolts have blue thread seal and they are tight and easy to bugger up. If you
do bugger one up, we can show you how we got out of trouble. Best take time
and stay out of trouble :)
 
#19 ·
There are 3 procedures to replacing that steering coupler. Ken (Panzerpuff) came up with an easiest way. I did it by pulling the Instrument Cluster, pulling out the Steering Shaft, and some other interior disassembly -- I don't recommend this way.

Ken suggests to just loosen the bolts to the Steering Gear Box to allow removal of the Coupler - no interior disassembly. I think he has a video showing how.

TIP: For Allen Head bolts on the Steering Coupler and the Distributor hold down, carefully clean the head and make sure you have the Allen Wrench properly seated. These bolts have blue thread seal and they are tight and easy to bugger up. If you do bugger one up, we can show you how we got out of trouble. Best take time and stay out of trouble :)
Carl thanks for the plug, I have a video here is the video clip below. If you unbolt the box you may as well check the steering box adjustment nut. There is a procedure in the EGv107 sticky. Using a crowfoot to do this is a royal PITA. Much easier if you turn the box and see what you are doing. http://www.benzworld.org/forums/r-c107-sl-slc-class/1330892-steering-box-adjustment-what-tool.html

 
#20 ·
Ken's videos are not only technically excellent, his video editing and camera work
excels too. Ken, what software do you use to edit your videos? I need to up my game.
 
#21 ·
Steering play

I was reading the various threads on the steering coupling and stumbled across some excellent material. I then had a look at my car (in the garage) and was a little surprised to see how close all these components are. I am used to Landrovers where nothing is compact, but everything is far way as these things are big and tall. Anyway I could grab the coupling from above to check for any play and I can confirm it is tight and sound. There is also no play on the various connecting rods and all play is within the steering box, between the input and output.

This means either my box is entirely shot or there is still some room to adjust the play out. I did read up about that as well and with my tool set I should be able to undo the locknut and adjust the set screw with the 6mm alan key. I was a little surprised to hear that you need to rotate it CCW to tighten, you would think it is opposite. Anyway I will work it out. If it does not work I will be changing to a recon box in a few weeks months time, as I really need to get the engine to run sound first.

If the Techron does not achieve it I will be taking the fuel distributor off to clean and overhaul with a gasket set. I have worked in carburetors a lot and looking at the various video's her it does not look too complicated other than a little delicate.
 
#22 ·
You don't mention alignment at the tire shop; how did that go? With a loose steering box perhaps they gave you a rain check? Techron works but it takes time. The fact that you are rolling means you do have the time. Also I would say your ignition overhaul is not yet done. Check timing as mentioned, your cap and rotor s/b renewed and you should inspect your chain and guides if you haven't yet -- We found half of one of mine in the sump when we loosened the pan to take off the front plate to gain access to the lowers.
 
#24 ·
Ditto!! Been using aerospace 303 on my kayaks, cars and other outdoor play toys as UV protectant for years. Great stuff. WD-40 is gummy garbage for these applications.
 
#30 ·
fuel relay

Ok officially got stuck on the parking lot with no start. Car not running great but Techron is slowly clearing the system of varnish and is running better every day.

So the car cranked, but no start. Could not hear the fuel pump. Removed a few panels and located fuel relay, but nothing obvious wrong. Checked and no power to the pump. Bought a jumper wire, got the pump running with direct feed and car started just fine and drove home.

At home checked it out and seems like the fuel pump relay was not providing a feed. I took it out and opened it up. The relay is a closed relay, but upon further inspection I noticed the main feed contact had a poor contact with dry solder. Resoldered, put it back and voila vehicle fired up again.

Well as I said running better every day!
 
#32 ·
pictures

Few pictures:

Fuel relay with dry solder joint
Old spark plugs x8
rear stabiliser link disintegration
Refurbed fuel pump assembly
Old tank fuel screen
 

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#35 ·
spark plugs

Hi Fish,

Well spotted, yes I purchased the spark plugs on line in advance and went by spec (non resister). When I removed the old ones (which seemed to have been fitted fairly recently) I noticed the resister types were fitted. Not making much of a difference, possibly better spark at cold start.

Also changed all the spark leads with Beru set. Cap and rotor had already been renewed by PO.

From what I understand the car was parked up as it was unreliable, which might well have been the cold solder joint in the fuel pump relay...

Hopefully she will be prove to be more reliable going forward!
 
#36 ·
Success! running fine now (when warm)

Hi All,

Changed the belts (only to find that the AC belt is a double and I bought only one) and took the car for a drive to pick up my (16 year old) daughter at a friend. Car was again running a little better, but hard to start. Had to drive around the block once to feel confident she would accelerate in traffic.

During cranking I noticed the battery was starting to give out, could hear some relays clicking while starting from the voltage drop. No date stamp, but figured would be an older battery, so on the way to pick up my daughter I picked up a new battery at O'reilly. Not the most perfect of fits, but dang! did she fire up quick!. Idle was just the most smooth ever and acceleration was effortless.

Idle is so smooth now you think she stalled. I am guessing that with the re-soldered fuel pump relay, stable voltage, new sparks, techron and all new fuel delivery things are looking up for the old girl.

This morning (cold in Houston - freezing in fact) I found my daily driver Jeep Wrangler had a flat, so was 'forced' to use the SL. Little weary. Start was difficult and had to run around the block to warm her a bit. Me thinking maybe the WUR is not working right. But within a few minutes - man did she run nice! 30 min drive the work was just a joy.

Let's hope she starts right tonight when I need to go home..
 
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