Author Topic: 4-Speed Shifter Linkage  (Read 13887 times)

Longtooth

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4-Speed Shifter Linkage
« on: August 08, 2006, 01:08:56 »
Just had another mishap driving up from SJ to San Raphael (~90 miles) after a great ride up the 4-lane 280... 90+ mph like a dream.  But driving stop/go thru SF somewhere just this side of the Golden Gate, when shifting into 2nd to take off from a stop-light, my shifter was like loooooose and dropped about 2 inches... no gears would engage!  Panicville in really conjested traffic!  I collected my thought quickly, lifted my shifter back up till I felt some resistance... then shifted into gear like it never happened... but when I let lose the shifter, it fell back down again .... so I lifted it back up, shifted to 3rd, and held it up the rest of the stop/go traffic and all the way to San Rafael... 2nd, 3rd, 4th, back and forth.

When I got to my San Raphael destination I started breathing again and then started searching for an open shop... no luck.  But the local MB dealer (R.A.B. Motors) diagnosed the problem over the phone and told me it was due to one or both worn-out split bushings that surround the spherical section of the shifter.... probably the bottom one (hence my shifter dropped thru).

I had no tools with me, and my sister-in-law didn't even have a pair of pliers.... some garden tools and a light-weight hammer (more like a tiny little mallet).  Anyway, I had driven up to San Raphael to participate in next days 1st Sunday Drive... so I was p.o.'d to say the least.  

I sat in the car and carefully figured out what it took to engage the gears, including reverse, and retain the ability to shift.  All I had to do was keep the shifter snugged "up" (vertically) to the approximate correct height, against some resistance (whatever was resisting some moving in the "up" direction).  If I pulled too hard in the UP direction I couldn't find the gears and everything go real loosey-goosy again, just like when it dropped down.

So I rigged a spring from one of those garden flags (wire with a colored plastic flag gardner's use to mark where they're going to pu a sprinkler... my sister in-law had a few left over from when she had her garden done about a year earlier).  The spring was simple... I bent the wire only slightly, taped one end (with blue painters masking tape) to the top end of the shifter shaft, srapping the tape around the wire and shaft for about half the distance down the shaft, and then the bent end of the wire near the bottom of the shaft with that bottom end stuck into the carpeting to keep if from slipping away.  Basically it was a spring column holding the shifter up, but still letting it shift thru the gears... but not so much upward force on the spring that it would pop out the top side.

Hey... don't knock it... it worked while I drove all the way back to my residence... stop/go traffic all the way thru SF (19th Ave on a Sunday morning with everybody else in SF taking the same path out of SF it seemed... Golden Gate was jammed too.  Lotta shifting required 'til I hit 280 and then it was 4th gear and 90+ mph again all the way home... well, I stopped for a Beer at Santana Row while waiting for my parts source to get back from lunch... and then leaving Santana Row .... my Jury Rigged shifter BROKE again!.... middle of shifting from 1st to 2nd!!!! Panic again!... calm overtook me long enough to "feel" my shifter back into position and then engage 2nd!  But clearly something had gone wrong... the shifter was really lose now... far moreso than it had been before I jury-rigged it.... so I had to "feel" it into position between shifts, then shift into next gear (and hope I'd actually engaged).

Got it home.... drove my other MB (my wife's) to my parts source... but he still wasn't back from lunch... so drove back to San Raphael at 80-85... saw a couple of CHP's on the prowl this time.

I took the shifter apart today.... sure 'nuf, the split bushings are shot to hell... the bottom one might as well have not been there at all (so my shifter fell right thru)... top one so warn it didn't take much pressure to pull it up thru the bushing either.  

Also found the chrome had worn off completely on the spherical section... down to copper... with some scratches in the copper... and the rubber guard underneith was lose... hence dirt, grime got in and between the shifter sphere and bushings and wore them out... bottom one more-so of course.

I also found there were two (2) washers between the split ring and top bushing, so somebody, at some time had 'fixed' the shifter's looseness (presumably) at some prior time by just adding another washer... which placed more pressure on the bottom bushing, so it wore preferentially.... 'til it let my shifter drop right thru.

I had a hellova time getting shift tube (with splines) separated from the actual gear shifter, even though I'd loosened the nut/bolt that snug's them together... so I figure these two parts (shifter linkage and gear shifter) haven't been apart since the car was new.

The two bushings on the bottom of the shifter (that attaches the shift shaft to the shift tube (with splines) were worn out completely on one side.... (side that get's the pressure when in 3rd and 4th... i.e. side closest to driver), with the other side just fine.... which make's sense... most of the time the car's in 3rd or 4th.

All the other bushings are fine... ones between the stiffner rods and shift bearing, for example.

So.... moral of the story is
    • Take your Big Blue Book with you on Trips[*/]
    • Take some tools (large and small cresents, limited set of open/closed end metric wrenches, 9mm - 19mm sockets & adaptors for & 3/8", & 1/2" drivers, a couple of extenders & some screw-drivers, pliers, etc)
    • Don't forget a couple of rags[*/]
    • some wire & duct tape


Had I been able to take my cover plate off the shifter & had I had some better tape and my trusty roll of malleable wire) I could have jury-rigged the shifter to last another month of SF 19th Ave stop/go conjested traffic without replacing the split bushings and gone on the 1st Sunday drive yesterday!!!... and my jury-rig would have been able to reside entirely under the rubber cover around the shift shaft!!! so nobody would have been the wiser.

All was not lost though... we (my wife, my sister-in-law, and I) had drinks (lots) and oysters (lots more) at Sams in Tiburon to soothe my wounds from not being able to participate in the Sunday Drive.... and besides, I was able to drive like a bat outtahell on 280 to (SF) and fro on a beautiful bay-area week-end, top down, and accomplished one of the missions of participating in a Sunday Drive... find out what-ever can go wrong and wring it out.

I'm not sure whether I should have the shifter rechromed (to make the spherical portion hardened with chrome and smoother for less abraisive wear on the split bushings) though.

Longtooth
67 250SL US #113-043-10-002163
'02 SL500 Sport

DaveB

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Re: 4-Speed Shifter Linkage
« Reply #1 on: August 08, 2006, 19:33:59 »
Hello Longtooth - are you sure that spherical section at the base of the shifter was originally chromed? I've got one here and it's also copper. There's a sharp border between the copper plate and the chrome plate on the shaft above, which leads me to believe that the lower (spherical) section was not originally chromed. But of course mine could be worn that way too.


DaveB
DaveB
'65 US 230sl 4-speed, DB190

Longtooth

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Re: 4-Speed Shifter Linkage
« Reply #2 on: August 08, 2006, 22:04:55 »
DaveB.... though I can't be sure, since mine also has the sharp borders (chrome/copper) as you describe, there's residual small area's (irregular islands) of chrome on the sphere... but none on the lever shaft portion of exposed copper for the 1/2 inch or so above and below the sphearical section.  I'm guessing that the original mfg'ing consisted of the area's outside the borders  chrome plated separately before or after the area in the sphere... probably to control thickness (diameter tolerances)of the sphear where it counts... or to use a different chrome or deposition method in that area. It's possible that the 1/2 inch above and below the sphear where copper's visible (but with no known means of being worn) were to 'tape-off' the section where chrome or some type of metal coating was plated in the area of the sphere.  At least that's my take from looking at the observations from an engineering/mfg'ing design point of view.  Seem's very poor engineering to me that the copper on the bearing surface of the sphere would be used as the direct bearing surfaces!... not to mention the residual small islands of chrome? I see in some small area's on the sphere.

I'm in contact with a restorer so will hear from him on the subject later or tomorrow.  The fact that my spherical portion have visible scratches in the copper indicates to me that there was a chrome coating on it at one time since copper's a relatively soft metal and easily abraided, worn....in an area where any dirt/grit will definitely accumulate over time.  A chrome plate would definitely be a preferred method of limiting wear & extending the wear-out period.  

Interestingly my BBB doesn't mention anything about the lever or sphearical section of it, but does describe wear and replacement of the split (or non-split in case of 1st version pre-'65) bushings surrounding the spherical section of the lever.  In fact, the reason for the 2nd version design was to make it far easier to replace the bushing!!!! so wear of the bushings were a known issue sometime before '65 when they changed the design.

Hence clean chrome surfaces with no dirt/grit between chrome and bushings would cause virtually no wear of either (grease or vaseline lubed.... not OIL!!!).  Considering our SL's have 100k + miles of them by now, and are approaching or are over 40 years old, it's a virtual certainty that various degrees of wear will have occurred, given various degrees of dirt that would eventually work their way between the bearing surfaces.... despite the rubber cover on the under-side of the shifter bearing to prevent??? dirt from easily entering.

Even though the split bushings (a plastic... Nylon type material?) would wear preferentially by design, leaving the worn ones in the car for extended period (like new to present?) would eventually let more and more dirt accumulate and embed in the plastic... causing eventual abraisive wear of the chrome plate on the sphear.  If chrome plate hadn't been there by design, then it's a certainty that the copper would wear even more rapidly... requiring the eventual replacement of the lever itself...quite a bit more expensive than replacing the bushings.

Some of the more experienced ones on this board would know from experience of removing / replacing the split or non-split bushings whether there was normally a thin chrome or other metal plating on the copper around the sphere itself... as opposed to the 1/2 inch strips above and below it on the lever column.

Longtooth
67 250SL US #113-043-10-002163
'02 SL500 Sport

psmith

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Re: 4-Speed Shifter Linkage
« Reply #3 on: August 08, 2006, 22:45:36 »
Hi LT,

Sorry to hear of your technical difficulties, it was a great drive, I posted some photos in the Photo forum.  Please feel free to call my cell phone number on the spreadsheet (not that anything is going to happen again), I carry a fair amount of tools as I am paranoid of a breakdown.

I had planned on driving up on Saturday as well, but unexpected houseguests foiled my plan.

Pete S.

miltnme

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Re: 4-Speed Shifter Linkage
« Reply #4 on: August 08, 2006, 23:37:16 »
hi longtooth

as a newbie, would you or others be kind enough to tell me where i can purchase a BBB?  

i am hoping to purchase a 280sl soon, and even though i am not a real wizard on cars, it would probably be wise to read up on things.

many thanks
jonathan

Longtooth

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Re: 4-Speed Shifter Linkage
« Reply #5 on: August 09, 2006, 00:32:40 »
johnathan... my BBB is a pass-me-down from my dad who got his from MB Stuttgart when he lived in Europe and also owned a '67 250SL... and a '62 or '63 190SL.... and a '59 180D he bought new on first arrival to reside in Germany.

So, I haven't the foggiest on how to find one, though I'm sure there are some being sold from time-time on E-Bay... as I've seen them there from time to time.  The problem is, I think, getting the right version.... the BBB's were appended with new publications from time to time as new mechanical modifications or additions were included.  For example, mine was originally published in '59... but has additions in newer publication of the same PN BBB thru '66 in any area's where there were changes in models (intoduction of W113's, for example, then the changes to 113's thru the 250SL's... so mine is pre-280SL's which came out in '68 (maybe late, late '67).  There's probably a slightly later update that included all the changes made thru the entire 250SL line up to and probably including the introductory models of the 280SL maybe.  

Either somebody on this site (probably one of the 4 or 5 star members) will have pointers to where to find the right PN manual and publication dates with the updates thru xyz month/year, or you may have to contact MB Classic Car (on the web).. but I'm told these BBB's are no longer stocked or reprinted any longer by MB.... but maybe their available now in micro-fiche or even perhaps on a DVD (with pics?)... but honestly don't know.  

It's an invaluable resource to find out what spec's are, torques, how to remove, test, re-install everything and anything, special tools required, trouble shooting methods for almost every conceivable problem in every area of the car... heating systems, electrical, mechanical... body, windows, etc.  If I understand it correctly, the BBB is the Shop Manual for MB Mechanics, though there are also other MB shop books for even more detail as I'm told.  As it is, mine's about 2.5 inches thick.

However, it's not a complete shop manual... as I've yet to find any reference to the 250SL's oil heat exchanger for example.... maybe this feature was introduced post '66 though.

Sorry I couldn't help... but you've got the right idea... get a BBB (Big Blue Book... color of cover)... MB shop manual. Even if you do no mechanical or electrical work yourself, you'll be able to figure out or limit what's wrong & what needs to be addressed to fix so an unscrupulous mechanic can't take too much advantage of your ignorance.... but I'm the analytic type, so I invariably try to isolate the problem source and root cause before I head off to a mechanic if I'm not inclined to fix it myself.  If nothing else it may save the mechanic some time in trouble-shooting the possible problems if you've already done your homework with the BBB.  Like I said in my original note on the shifter problem, had I had my BBB with me I would have been able to diagnose the probable cause myself (one or both split bushings were shot)... and had I even had a small cresent, a pair of plyers, some duct tape, and some malleable wire I'd have been able to jury-rig the fix well enough to keep driving for another month in stop/go traffic... and the tools above could have been had for ~$5 any local hardware store had I had my BBB to figure out what the problem was and how to go about dissassembly to the point I could fix it without doing even more harm and making it impossible to shift at all).

So first... BBB (and a flashlight in case it's dark)... then tools.  Sounds ominous... having to drive around with a small tool tote in the trunk (that I'd have to secure from sliding around with my driving style) ... but on the other hand, the 113's are emininatly fixable with standard tools, unlike the modern cars.... parts are the problem if you can't temporarily find a fix with some alternate part carried by a local autoshop).  Besides, if you're like me, you'll break something that requires just one little tool you decided to leave out of your tote to fix it).  Murphy rules.

Longtooth
67 250SL US #113-043-10-002163
'02 SL500 Sport

Longtooth

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Re: 4-Speed Shifter Linkage
« Reply #6 on: August 09, 2006, 01:07:49 »
Pete - ce' la vie as they say in France.  I'll put your cell number in my wallet now... AND carry my BBB and some tools from now on.  I hate to do this, but given the circumstances of this latest little difficulty, it's only prudent.  In this case though, I wouldn't have bothered you since it would have delayed your own participation in the Sunday Drive... and I'm loath to let my little probs affect others free-time & plans.

Besides, I got to sit in the sun on the bay at Sams, slurping oysters and drinking beer, glancing at the other scenery from time to time (serepticiously),and playing referee between my wife and her sister... my job is to keep the peace between them....sibling rivalry's still strong even at their ages!... not to mention I get to tease them both to my hearts content and semi- get away with it.  So I had fun anyway.... and driving 280 with low traffic and not a CHP in site is, as you know, one of the bay area's fun high speed 4-lane mostly... sometimes 5, occasionally only 3 (each way for those that aren't familiar with 280 from SJ to SF) free-ways... with scenery to boot, top down, sun a-shining bright.

My big dismay is that I thought my mechanical's were a-ok... and now  twice, one each of last 2 Sunday Drives, they've shown me that some of them aren't.  ... hidden latent problems needing to be wrung out.... my rationalization as spoken by an engineer. Nothing serious yet (knock on wood), fortunately... just disruptions in plans.  It's just part & parcel of making the car as bullet proof as I can which is my long-term view and intent anyway.

Longtooth
67 250SL US #113-043-10-002163
'02 SL500 Sport

miltnme

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Re: 4-Speed Shifter Linkage
« Reply #7 on: August 09, 2006, 13:50:00 »
longtooth

thank you so much for the info on the BBB, i will start doing some research on the web and see what i might beable to find.

many thanks
jonathan

psmith

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Re: 4-Speed Shifter Linkage
« Reply #8 on: August 09, 2006, 14:32:15 »
Jonathan,

I got a reprint of the BBB and unfortunately most of the photos are so dark you can't see much.  I recently got the bbb on CD from the MB Classic Center in Irvine for $20.  The photos are much better, but it is a little tricky to navigate at first.

Pete S.

Longtooth

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Re: 4-Speed Shifter Linkage
« Reply #9 on: August 11, 2006, 22:37:27 »
I found out that the Copper section at the spherical section of the shift lever is the way it comes from the factory... i.e. not chromed, much to my engineering surprise.  

Reasons aren't entirely clear though, as Chrome will make for a smoother, lower wear, lower friction surface, though the latter is not really significant, as lubricants (grease) makes it effectively mute.  Apparently, from what I've been able to find out, if the lever is fully chomed, including the spherical section, it makes for a slightly more resistant shift, which means that the interference between the split spherical bushings and the spherical section of the shift lever are greater with chrome... so the spherical bushing design (& tolerances of mfg'ing) was apparently designed for a given interference condition that also apparently made for some of the greatest interferences having too much resistance in shifting (those with tolerance stack-ups between lever and bushings causing the most interference).  The best solution would have been to reduce the diameter of the shift lever's steel spherical section and continue with cu and chrome plating as it had been.  

But, as in all business, the best engineering solution may have mitigating economic conditions that make for cheaper solutions albeit with some compromises in reliabilty.  For example, if there had already been a large inventory of steel (yet unplated) levers and an additional expense of retooling costs to mfg'er the spherical bearing to a slightly smaller diameter, and/or tighter toleranced Outside Diameter (OD), then it would be far cheaper just to mask off the sphearical section from being plated by the chrome plating process.  Another solution would have entailed changing the mold(s) for the bushings... also a retooling expense, since material has to be added to the mold spherical surface to make the bushing ID (inner diameter) larger.... so again, a far cheaper solution just to leave off the chrome layer.

The drawback to the cheaper solution isn't apparent in the near term anyhooo... since the wear-rate of the bushing with cu sphere isn't going to be perceptible in resistance of shifting (becoming looser... easier... and hence also potentially falling out of gear on some occasions) for the highest proportion of drivers for probably at least 50k-100k miles of average shifting (not a lot of stop/go commute driving in the 60's, and the 113 wasn't designed primarily as a city driver anyhooo, of course... so not a critical reliability cost or performance issue except for a smaller fraction of drivers.... and to mitigate the cost of fixing the condition of being too loose due to wear, the bushing was redesigned to be a split bushing, making replacement far easier and cheaper than in the full spherical bushing prior to '65.

That's my conjecture to explain why MB, which otherwise seems to use excellent engineering solutions to enhance reliability over time (by my observation of several mechanical systems on the W113), used a cheaper, but lower reliability solution to a design interference (probably tolerances issue) condition.

It would be interesting to know whether the original 230SL's actually have / had a fully chromed shift lever at the spherical section.... though full restorations by quality shops may have the shift lever re-chrome plated and unless the chrome plater is told to mask off the section surrounding the sphere after Cu plating and polishing, the restored shift levers will sometimes have the spherical section chrome plated --- per restorer's experience in both his own restorations (which require restripping and re-doing), and in some restorations that have been previously restored by others....

Longtooth
67 250SL US #113-043-10-002163
'02 SL500 Sport

Raymond

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Re: 4-Speed Shifter Linkage
« Reply #10 on: August 13, 2006, 06:40:14 »
Pete, try a website called Books4cars.com  They often have used originals for around $100.

Longtooth, are you sure your handle shouldn't be "Longwind" :mrgreen:

Ray
'68 280SL 4-spd Coupe
« Last Edit: August 13, 2006, 06:40:49 by Raymond »
Ray
'68 280SL 5-spd "California" Coupe

Longtooth

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Re: 4-Speed Shifter Linkage
« Reply #11 on: August 16, 2006, 03:42:51 »
Ray... you're right.  

Got my shifter back together with new bushings.  Shifts like new.

And... thanks for the tip on Books4cars.com... I'm looking for a PN manual & 280SL version BBB.

Longtooth
67 250SL US #113-043-10-002163
'02 SL500 Sport

Longtooth

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Re: 4-Speed Shifter Linkage
« Reply #12 on: August 30, 2006, 02:25:29 »
Just a hint on a method of returning a repaired (bushings at least)the gear shift assembly to it's rightful position.

The assembly consists of the bearing plate, to which there are 4 other parts attached.... the 2 rods (on either side of the plate), the shift tube (splined on end that fits into the splined female end of the transmission shift lever, & attached to the bottom of the shift lever itself on the other end), and the shift lever.

This assembly has to be placed thru the hole in the body, fed up to get the shift tube splines to engage the female splined lever at the transmission, and the 2 rods attached to the bolts on either side of the mount plate on the transmission.

The problem is that both rods swivel at their mounts on the bearing plate, and the shift tube with splines also pivots (up/down and some side to side), so that when the shift tube finally engages the splines in the female splines, the rods are hanging down on either side of the transmission... and it's a bi...tch to reach down and try to retrieve them to lift the far end up to place over their studs on the transmission cover plate.

So... what I did is attach a couple of wires to the rods near their tranny end.... and reached into grab the wires to lift the rods up after the splined shift tube was engaged & inserted at least 15mm (spec'ed minimum engaged distance)with the female splines.

I used malleable wire so that the wires wouldn't fall down on either side of the drive shaft and/or be unreachable after inserting the asm.... & strings or nylon fishing line are too unmanageable... you can't give them a set to make it easy to reach after inserting the asm.

A more certain way to reach the wires after inserting the asm is to string a string from the hole in the body at the tranny end to the hole at shift lever end, leaving the string hanging out a foot or so at the tranny hole end, and attach the string to the wires before inserting the asm into the hole at the shift lever end.  Then, after inserting the asm to position thru the hole, pull on a string coming out of the hole at the tranny end to pull the wire attached to the rod to a position you can grab the wire and pull up the rod of choice from the side of the tranny / drive shaft.  

In other words, you fish the string in reverse to attach to the wire before inserting the asm, so that you can fish the wire to fish the rod after inserting the asm.

After the splined shift tube is inserted the minimum distance, the rod ends are pulled up (with my wires) and placed over their respective studs.  Then the location of the rod's bolts attaching them to the bearing plate (on either side of the shift lever) are centered front to back between the tapped holes in the body to which the top plastic cover is attached by the 4 bolts).  

To center the rod's attachment bolts (at the bearing plate end) you loosen the bolt which cinches the splines to one another at the tranny end, then lift the rod ends off the tranny studs and rotate them in or out (depending on direction required to center the other ends between the tapped holes at the lever ends) such that both rods are exactly the same length and extending or shortening the rod length.  Then tighten the securing nut snug against the rod ends (rotating rod ends).

The part about keeping the rods exactly the same length isn't done easily unless you set their lengths while the asm's outside the car.  Once the lengths are set equal (snug up the securing nut finger tight to secure these lengths), when adjusting the lengths inside the car each rod end get's rotated the same number of turns in the same direction... which maintains equal length rods.

If perchance the rod ends aren't able to be loosened so that you can rotate them.... a likely event since the area under the body is open to atmosphere and unprotected therefrom, then my suggestion is to NOT change EITHER rod end... unless they're already unequal in length, and then you'll be force to change one or both lengths... hence one or both rod ends have to be freed up to rotate freely... don't forget to loosen the securing nut that snugs up against each rod end before trying to unscrew or loosen the rod ends to rotate.

You may be asking why the rods have to be or should be equal in length in the first place.  If they're not, then
 1. the bearing plate will not be square to the world inside the car... but be canted right or left slightly.... which by itself isn't a real problem, buuuutttt, then as a consequence

 2. the bearing plate will slide less freely back and forth between the rubber vibration dampers (& noise inhibitors).... which it has to do when engine heats up transmission causing the actual distance between the body at the 4 tapped holes around the bearing plate to be reduced (by thermal expansion of engine and transmission), and

 3. put a side-side moment (force)on the shift tube (one that's attached to the base of the shift lever and at the female end of the splined shaft that sits on the tranny and does the actual shifting of gears) as well as on their forked end attached to the shift lever... which

 4. accelerates wear on the bushings (4 of them) at the attachment of the shift tube to the shift lever... which

 5. leads to premature failure of those bushings and loose connection between the shift lever and shift tube in side-side action... which

 6. forces shift lever to have to move further side-side to shift from neutral to reverse... neutral to 1st or 2nd, & from 2nd to 3rd, which causes

 7. the shift lever shaft sides nearest the bearing plate to hit the bearing plate top edges and require exceptionally higher forces by driver to get the shift tube to rotate far enough to actually get the gears to engage.... while simultaneously putting more torque on the bearing plate which

 8. causes premature wear of the split bushings surrounding the spherical section of the shift lever... which ultimately

 9. makes for either a very losey-goosy shifter, and, even

 10. letting the shift lever fall down out of the bearing plate bushing retainers... so that

 11.  .... you may end up in heavy stop/go traffic some and suddenly find your shifter has dropped a couple of inches and you can't find the gears!!! read my introductory post on this topic for what that means.

Of course if you don't drive the 113 much, or don't shift much.... like a straight shot from your parked position in neutral to the free-way or highway with 1 shift to 2nd, 1 to 3rd, and 1 to 4th.... and back down again when you return to your normal parked position, then you shouldn't have to worry much about how premature the wear might be when using shift rods of different lengths.

The main reason for my posting this entry was just
 

1. provide a hint about making the job of re-installing the shift asm easier and less hassle free by using wires attached to near the rod ends (end that goes to the tranny studs) before inserting the asm back thru the hole in the body and

2. to provide some insight as to why the rods should be equal in length.      

Maybe there's an easier way to get the rods into position... but I couldn't figure it out if there is.... one rod or the other (sometimes both) was (were) always out of reach down the side of the tranny or drive shaft when I inserted the asm to engage the splines. .... and I have long fingers.  Of course, you could always cut a bigger hole at the tranny end... then fab a cover and seal to match... and make new self tapped holes in the body... but that weakens the body's stiffness somewhat.


Longtooth
67 250SL US #113-043-10-002163
'02 SL500 Sport

Douglas

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Re: 4-Speed Shifter Linkage
« Reply #13 on: August 30, 2006, 04:36:50 »
Here's a reference photo showing the copper base of the shifter that I took while Achim and I swapped out my shifter bushings:



Download Attachment: 26793781403_0_ALB.jpg
30.14 KB

Douglas Kim
New York
USA

Naj ✝︎

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Re: 4-Speed Shifter Linkage
« Reply #14 on: August 30, 2006, 04:51:10 »
Couple more gearshift pictures if it helps...

Gear Shift Bushes detail:
Download Attachment: GrShft_parts.JPG
32.63 KB


Splined Transmission Joint
Download Attachment: GrShft_TrmEnd.JPG
32.73 KB

68 280SL
68 280SL

bsimaz

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Re: 4-Speed Shifter Linkage
« Reply #15 on: August 30, 2006, 08:37:07 »
Very good story.   I am not currently carrying any tools with me but I will from now on.  I am just getting my 230 back on the road.  

See:  http://bill230sl.blogspot.com

Just put my pictures there.   Will have the finished product pic soon too.

Similar to your story,  While in the process of fixing, I had a small problem with shifting (it's an automatic).   Found the bushing on the shift rod to the transmission was old and had broken.   I bought a new one and the tech at K&K mfg told me to buy 2 of them and replace both.  I did purchase two but only replaced one.   After all it is working fine.   Well on my first drive with the car I pulled into the store and upon returning I found the other (upper) bushing had broken too.  Here I sit, miles from home, no tools, and unable to get the car in gear.   Well,  I started the car put on the emergency brake,  crawled under the car and manually shifted into drive.   That got me home.  All fixed now.

I learned a few things from this.   Follow the advice of folks that know what they are talking about.   Saves time and headache later one.  And, carry a few tools with you.  Especially when driving a 40 year     old car.

Bill Simaz
'66 230sl
Back on the Road

Longtooth

  • Guest
Re: 4-Speed Shifter Linkage
« Reply #16 on: September 01, 2006, 04:31:38 »
Naj... the photo's you supplied are great.... I didn't think of doing this when I was hot & heavy into fixing mine.  I'll try to remember next time I do some work to have my camera at the ready.... at least to remind me to photo things that would be more easily and concisely explained with the help of a pic  .... pic worth a thousand words as the saying goes.

I notice though that your photoes show 2 retainer rings... only one is shown and required in the BBB detail section and only one was in mine when I disassembled everything....the one above at the top of the top split bushing and corregated washer.  I have a gut feel that when encountering either 2 retainer rings or 2 corregated washers, there reason would be that the split spherical bushings had warn already some, and by adding the additional interference, it tightens up the lever spherical section within the spherical bushing... but also causes a subsequently faster wear rate... so the quicky fix which is dirt cheap to do (just pop off the knob from the shift lever, pull up the rubber cover, and slide another retainer ring down and slip it into the slot, forcing the previous one down and applying pressure to the warn split bushings, for example) is just a postponement of unknown duration 'til the shift lever drops 2 inches and you can't engage a gear in traffic when you need to.

By the way, don't lube the asm or any of the bushed joints with oil... use bearing grease or vasoline (per BBB's admonition in bold type), since oil causes the bushing material to degrade rapidly.  Specifically what oil does is dissolve and leach out some of the plasticizers in the polymer material.... which makes them less resiliant and brittle, so that when forces are being applied to them they produce greater wear at the most deplasticized regions (higher pressure on those spots)... which upon wearing therefore reduces the total bearing area, leading to increased pressure on the remaining perhaps still partially plasticized area's, causing them to wear even faster, thus snowballing to an ever increasing wear rate until finally you push or pull on the lever to engage a gear and the lever's spherical section either pulls up out of the bearing plate or falls thru it (mine did both!).... and you can't engage the intended gear ... or any other for that matter, 'til you manually find the spot where the spherical section of the lever should be located, if you're lucky, and then shift into whatever gear you can.  At that point it's all about pure feel.

At least I didn't have to crawl under the car to engage "drive" as Bill Simaz had to do in his automatic.  I have to hand it to Bill Simaz... I would have called AAA and had the car flat-bedded to my favorite mechanic shop in the area or lockit up and left it for the next day to get taken care of.  

Interesting that the introduction of 230SL in '64 for availability, and the design change pre-'66 (modification shown in my BBB beginning Nov '65) to the bearing plate hole and spherical bushing, only allows for less than 2 years of driving before MB decided the need to make the split spherical bushing replacement easier on the MB mechanics, huh?

By the way, the design change pre-'66 was to 3 items... shift lever itself bent forward 55 degr (for more elbow room when shifting), full spherical bushing modified to having 2 halves (upper and lower halves, hence "split" spherical bushing), and features in the bearing plate 'hole' were added to better enable easier replacement of the spherical split bushings.... notably the top side of the hole was redesigned to enable both split bushings to be replaced by pushing them both down ... the bottom one stretches to let it slide over the spherical section of the shift lever while lever's still attached to the shift tube below the spherical section... and the top spherical half just sits down on top of the spherical section... both then retained in place by the corregated washer and retainer ring... so the bearing hole at top end now has a recess to accept the retainer ring.

In Naj's photo you can see the shelf at the bottom of the bearing plate 'hole' (which keeps the lower split spherical bushing from falling thru ('til the bushing wears out like mine did), and the recessed ring on the Inside Diameter of the hole at the top which accepts the retainer ring.



Longtooth
67 250SL US #113-043-10-002163
'02 SL500 Sport