Author Topic: HELP! fuel guage trouble  (Read 2152 times)

lurtch

  • Full Member
  • Silver
  • ****
  • USA, CA, Santa Rosa
  • Posts: 368
  • " ICON 66 "
HELP! fuel guage trouble
« on: July 14, 2019, 02:10:39 »
Hello All,

    This morning I wanted to join my touring group for a cruise around a local lake. Did not happen because electrical gremlins now inhabit my instrument cluster. The indicator needle will not come off the peg in spite of the almost full tank. I suspect corrosion has locked up the delicate meter linkages? I used to be able to knock it with my knuckle to get it off the peg. No more.

 I especially need to monitor fuel quantity because mine is a 230SL with the smaller tank. I would be OK with doing the tour (200+ miles) if my odometer was functioning, but those gears stripped out earlier this year, so I've got NO fuel quantity measurement capability.

Questions:  has  anyone on the website had an cluster refurbished?  if so, where and how much $$$?

There is a cluster on eBay right now (99.00 US) that I will probably buy so I can cannibalize it for the fuel guage. Has anybody done this transplant procedure?  if so, please PM me?

Regards,

Larry in CA



Larry Hemstreet  in  N. Cal.

1966  230SL  Met. Anthracite w/ Maroon leather
1981  300TDT (Concours, 86K w/ GETRAG 5sp)
1982  300TDT (rough and rusty)
1986  560SEC (totaled)
1991  300TE (gifted)
1998  E320 (sold)
2004  E320 wagon (gifted)
2008  CLK550 cabriolet

UJJ

  • Full Member
  • Silver
  • ****
  • USA, CA, Grass Valley
  • Posts: 326
Re: HELP! fuel guage trouble
« Reply #1 on: July 14, 2019, 13:21:02 »
Hi Larry

How do you know the problem to be the gauge and not the sending unit?
I had trouble with the sending unit on my 280SE 4.5 (W108). A thorough cleaning took care of that.
I never had trouble with either of these on my Pagoda.
I had my Speedometer serviced/changed by Palo Alto Speedometer.
It included the required change to the odometer (new gearing) to Diff 3.26 and a new bezel besides the overhaul they do. $180.00 plus shipping.
Best, Urban
Urban Janssen
Grass Valley, CA
1968 280 SL - 4speed manual
173 anthracite grey

teahead

  • Associate Member
  • Gold
  • *****
  • USA, WA, Des Moines
  • Posts: 781
  • aka "Rob"
Re: HELP! fuel guage trouble
« Reply #2 on: July 14, 2019, 16:32:43 »
Right, check the sending unit.  Maybe pull it out and and test for voltage changes as you move the sending unit.
1970 280SL auto, AC - aka "Edelweiss"

doitwright

  • Full Member
  • Gold
  • *****
  • USA, IL, Willowbrook
  • Posts: 645
Re: HELP! fuel guage trouble
« Reply #3 on: July 15, 2019, 01:39:51 »
There are YouTube videos showing how to disassemble the fuel sending unit. Be very careful if you attempt this since there are 2 very fine wires that the float slides on. I cleaned one from a Porsche successfully and found detached wire in one I removed from a 220SE Coupe. W108’s use the same sending unit as my late model W113.
Frank Koronkiewicz
Willowbrook, Illinois

1970 280SL Originally Light Ivory - Now Anthracite Gray Metallic

Garry

  • Full Member
  • Platinum
  • ******
  • Australia, Victoria, Kyneton and Brisbane Queensland
  • Posts: 5181
  • Audit Committee
Re: HELP! fuel guage trouble
« Reply #4 on: July 15, 2019, 06:45:44 »
Larry,


My fuel gauge occasionally sticks and i tap it and it corrects, exactly as yours had done.  To me that would indicate that by tapping it and it then correcting the reading the problem is in the gauge rather than the sender unit.


I would have thought buying the unit on ebay and changing them over would be the cheaper way to correct.
Garry Marks
Melbourne/ Kyneton, Brisbane. Australia
1969 MB 280SL 5 speed RHD SOLD.
1965 MB 230SL Auto RHD Lt Blue 334G, Top 350H, 213 Leather, Tourist Delivery.
1972 MB 280CE Auto RHD 906G Blue Grey
2005 MB A200.
2006 MB B200
2019 Izuzu DMax 4x4 with Slide-on camper.
2022 Volvo XC40 Twin Electric

ja17

  • Full Member
  • Platinum
  • ******
  • USA, OH, Blacklick
  • Posts: 7313
Re: HELP! fuel guage trouble
« Reply #5 on: July 15, 2019, 13:53:19 »
The easiest way to check the sending unit is to remove it from the tank, connect the plug, turn on the ignition and rotate the sending unit up-side-down. The gauge on the dash should move from empty to full.
Joe Alexander
Blacklick, Ohio
1969 Dark Olive 280SL
2002 ML55 AMG (tow vehicle)
2002 SLK32 AMG (350 hp)
1982 300TD Wagon turbo 4spd.
1963 404 Mercedes Unimog (Swedish Army)
1989 flu419 Mercedes Unimog (US Army)
1998 E430
1974 450SLC Rally
1965 220SE Finback