Author Topic: Turn signal canceling  (Read 2621 times)

FresnoBob

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Turn signal canceling
« on: November 14, 2020, 16:56:52 »
I've read that repairing the turn signal lever is a snake pit of springs and catches, but my turn signal cancels on left turns, but only intermittently for right turns.  I read the 2009 post by Allen using shrink tubing and CA glue (not sure what that is).  Is this still the preferred method to repair this? 

« Last Edit: November 14, 2020, 17:18:19 by FresnoBob »
Bob Comstock
1966 230 SL Euro Auto
2017 AMG C43 Cabriolet

66andBlue

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Re: Turn signal canceling
« Reply #1 on: November 14, 2020, 18:04:35 »
Bob, before you tackle the repair make sure that the steering wheel is in the correct radial position. See https://www.sl113.org/wiki/Electrical/SteeringColumnSwitch
There is also a link to another repair method that members here have used.
Alfred
1964 230SL manual 4-speed 568H signal red
1966 230SL automatic 334G light blue (sold)
1968 280SL automatic (now 904G midnight blue)

Pawel66

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Re: Turn signal canceling
« Reply #2 on: November 14, 2020, 19:47:36 »
Indeed: a simple check is to remove the steering wheel and see if the mark on the top of the steering shaft points upward, more or less.
Pawel

280SL 1970 automatic 180G Silver
W128 220SE
W121 190SL
G-class

FresnoBob

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Re: Turn signal canceling
« Reply #3 on: November 16, 2020, 23:17:17 »
I tried to inspect and repair the turn signal canceling issue, but my first attempt was unsuccessful.  I've confirmed the alignment mark is nearly vertical, but I'm not sure how precise this needs to be.  I doesn't make sense to me that this is highly critical.  It also seems the 230 SL (my car) and the 280 SL in the Tech Manual are different in their canceling mechanism.  Is this correct?  I have a square ended protrusion from the signal switch itself that is suspended by two springs such that when the stalk is moved either up or down, the square ended protrusion extends away from the switch.  This protrusion seems to ride on the column, but I don't see a pin that would strike this protrusion.  My left turn self cancels, but the right turn doesn't, so at least it is functioning somewhat. 

Any suggestions are most welcomed!
Bob Comstock
1966 230 SL Euro Auto
2017 AMG C43 Cabriolet

Benz Dr.

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Re: Turn signal canceling
« Reply #4 on: November 17, 2020, 00:14:15 »
Well, you could always keep turning left. Eventually, you would find your way back home. :) ;)

 I told a customer the same thing one time and he didn't laugh either......... ;D
1966 230SL 5 speed, LSD, header pipes, 300SE distributor, ported, polished and balanced, AKA  ''The Red Rocket ''
Dan Caron's SL Barn

1970  3.5 Coupe
1961  190SL
1985   300CD  Turbo Coupe
1981  300SD
2013  GMC  Sierra
1965  230SL
1967 250SL
1970 280SL
1988 560SEC

enriquegarcia

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Re: Turn signal canceling
« Reply #5 on: November 26, 2020, 11:43:52 »
Bob,

I repaired my self-cancelling function using the shrink tubing trick you mentioned, as described in this Forum. (My turn signals were not self-cancelling in either direction, so Dr. Benz's solution was not an option.) I was skeptical, but that trick really worked! I had my assembly off the car and totally disassembled on the work bench because I had other problems, but you can do it without pulling the unit completely out of the steering column. (BTW, I can confirm that the turn signal assembly is an exquisite viper's nest of springs, pins, cams, levers, rollers and sliders. But no gears, so a cake walk for any experienced watchmaker.)

I did not use CA glue (because I don't know what that is and I don't think any adhesive would stick to the nylon tab), but I did slightly roughen the sides of the nylon tab with a sharp knife to give the shrink tubing something to bite into. And I did use a double layer of shrink tubing. As the tubing shrinks (I used the hot tip of a soldering iron as the heat source), it automatically forms a little nipple at the tip of the tab. If the nipple is too long, the turn signal lever will not hold the turn position (ask me how I know), so just trim a little bit off with a sharp knife. All it takes is one or two thousands of inch of added length to the worn tab. The tab (or now the nipple) works against a cam (not a pin) on the steering column.

I don't remember who came up with this solution, but many thanks to all those who have contributed ideas in this Forum!

Enrique Garcia
Euro '68 280SL 4-speed

enriquegarcia

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Re: Turn signal canceling
« Reply #6 on: November 28, 2020, 00:08:03 »
Upon re-reading my reply above, I noticed a typo: should be "thousandths of inch". Hope nobody tried adding thousands of inches of length to that little tab. My bad!
-Enrique