Does anybody know the capacitance of the caps in the Bosch blinker relay in the w116? I do not have the towing package.

I can't read some of mine and I don't want to have to remove them from the board if I don't have to. Still need it to drive!

I know you can gut it and replace it with a Hella unit, but I could aso just replace the caps for a couple dollars. If somebody has taken it apart and knows the numbers that would be swell indeed! Thanks

i want to say the two caps were 100 uf, but not 100% sure. i bought a few at radioshack and tried them until i found which one got the rate right. it seems to me that 22 was too fast and 220 too slow. just make sure they are rated for 15V at least. (i am presuming your W116 flasher is similar the one from my '77 W123.)

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'77 240D, 504H, OM617.952, etc.

This is what the caps say. I desoldered them and this is all they say unfortunately.

Big gold cap:
A+GPF
11.75
Elko 220 uF 6V-
Size: 14mm tall x 9mm diameter

Medium gold cap:
11.75
22/10
Size:11.5mm tall x 4.75mm diameter

Small blue cap:
16v
4.7/
015 FA
Size: 11mm tall x 3.3 diameter

you can fairly easily tell because the physical size of electrolytic capacitors will stay pretty constant over time. i.e., a 220uf/16V unit from the '70s will look the same as one does today, while 500uf would be about twice the size (voume).

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'77 240D, 504H, OM617.952, etc.

Not true, actually. Caps are nearly half the size of the ones I replace in early 1990s era electronics.

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RenaissanceMan Labs: where the future is being made today.

Garage:

2017 Chevy Colorado Diesel (nanny state emissions)
2005 Volvo S40 T5 AWD, 77k
1987 Mercedes-Benz 300D turbodiesel, 4 sp auto, 156k - 28.7 mpg
1996 Tracker 4x4, 2 door, 16v, 3 sp auto. 113k - 28.6 mpg

WARNING: this post may contain dangerous free thinking.

Yeah just look at my photos. On digi key you can see the sizes and they are quite smaller now. I was a bit concerned about the wire gauge on them. Not sure how much current they need to handle.

The leads are sized such that they will not melt if a fully charged cap is discharged. Don't worry about that, the electrical engineers already did the worrying for you

__________________
RenaissanceMan Labs: where the future is being made today.

Garage:

2017 Chevy Colorado Diesel (nanny state emissions)
2005 Volvo S40 T5 AWD, 77k
1987 Mercedes-Benz 300D turbodiesel, 4 sp auto, 156k - 28.7 mpg
1996 Tracker 4x4, 2 door, 16v, 3 sp auto. 113k - 28.6 mpg

WARNING: this post may contain dangerous free thinking.

True, cool. Thanks! Brake caliper started leaking so I can't drive it now anyway. Looks like a good opportunity to desolder the caps. I'll update the proper specs once I do that.

Ok so I bought new capacitors. I got them locally in Toronto from Creatron Inc. They have a good website and you can order online and they shipped them same day. I had them the very next day.

You can use these radial style caps even though the existing ones are axial style. Just be sure to get the positive and negative sides in the right hole, the holes are marked and the capacitors have a "-" symbol on the negative side. I just used a 30W pencil style soldering iron. You need one with a point so you can get in there properly. Don't try this with a big 100W gun style, they get far too hot!

I had trouble with the middle cap getting it into place. It's best if you can clear the holes of solder but that can be tricky. If you can't get the holes to open up once the old cap is out you can use a piece of wire to wick the old solder out of the hole. Then you can drop the new cap into place and just heat the wire and hole up from below and a little dollop of solder will wick into the hole and seal it all together.

The blinker works great now even when below freezing. The resulting blink rate is just slightly less than 2 blinks per second. I don't know what the normal cadence is for these blinkers. I know American cars blink at about 1 blink per second and that seems so boring and slow to me. It seriously puts me to sleep, so I kinda like this 2 blinks per second rate.

I tried switching my bulbs from 26/6W to Osram 21/5W bulbs and it made absolutely no difference in the blink rate.

This car blinks at 1.5 blinks per second. But I have no idea if this is the original relay: https://www.youtube.com/watch?v=ojLJK0JxowE

I got the following caps from Creatron Inc:

CAPAE-647050
Electrolytic Capacitor - Capacitance Value : 4.7μF 50V (2 Pack) CAD$0.50

CAPAE-722016
Electrolytic Capacitor - Capacitance Value : 22μF 16V (2 Pack) CAD$0.36

CAPAE-822016
Electrolytic Capacitor - Capacitance Value : 220μF 16V CAD$0.50

If you are in the USA, you can order new capacitors from Digi Key.
These are the ones you could use:

493-10470-1-ND CAP ALUM 4.7UF 16V 20% RADIAL $0.24

493-10393-1-ND CAP ALUM 22UF 16V 20% RADIAL $0.71

1189-2190-ND CAP ALUM 220UF 16V 20% RADIAL $0.45

Attached Thumbnails

     

With electrolytics the important thing is NEVER use a lower voltage replacement.
Higher voltage ones are the way to go.
Often the uf value is used as a timing portion of a circuit and should be adhered to.

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1985 300D 198K sold
1982 300D 202K
1989 300E 125K
1992 940T

"If you dont have time to do it safely, you dont have time to do it"

"The democracy will cease to exist when you take away from those who are willing to work and give to those who would not."

i stand corrected! i should have only related the ones of the same vintage to each other.

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'77 240D, 504H, OM617.952, etc.

Yeah I suppose, The leads seem to be the same as the resistors in the circuit anyway. The old cap had much thicker leads though which you can see in the photo. I haven't smelt anything melting so I'm sure it's good!