Author Topic: Question about early 230sl fuel sending unit  (Read 2791 times)

Charles 230SL

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Question about early 230sl fuel sending unit
« on: July 10, 2014, 03:16:17 »
Before installing my fuel tank, I thought it'd be a good idea to check the rheostat on the fuel sending unit. The rheostat windings/contacts appeared to be in great shape and the low-fuel indicator checked good with my meter. As I was replacing the cover plate, I noticed there was no gasket between the cover plate and the sending unit housing (houses the rheostat windings and contacts). On a full tank of gas, seems gas could seep into the housing and contact the rheostat windings and contacts. Has anyone disassembled one of these early sending units and noticed there's no gasket for the cover plate? Is this normal?

Once installing the fuel tank, is there a single best way to bleed the fuel lines and pump?
thanks in advance for any recommendations.. Charles




ja17

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Re: Question about early 230sl fuel sending unit
« Reply #1 on: July 10, 2014, 08:03:17 »
Hello Charles,

No need to worry, these units are designed to work submerged and flooded with fuel.

In regards to starting the engine...............for best results, remove all spark plugs, crack loose each injector line at the injectors, and crank the engine with full throttle. as fuel emerges from each injector line, tighten it up. When all are tightened, crank a little more then install all spark plugs and start the engine.   Otherwise, the engine will start without any dis-assembly or spark plug removal, just crank at full throttle. This method is much harder on the starter and the battery.
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

Charles 230SL

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Re: Question about early 230sl fuel sending unit
« Reply #2 on: July 10, 2014, 21:17:43 »
got it,, thanks Joe!