Tuesday, July 24, 2012

VW Bus Fuel Sender

The fuel gauge in the VW has been reading total and complete wonkiness since I got the bus.  This is OK if you are omniscient and need no such superfluous luxury items as bourgeois as automobile gauges, but for the unwashed illiterate plebes like me, not so good.  So I piled on to the web and ordered a replacement gauge from a prominent VW parts distributor.  Not so good.

The Split Bus has an access problem designed into it, in that to get to the gas tank, and therefore to the sender, you have to pull the engine.  Unless you are a retired college professor who likes to work alone and not be bothered by people 'helping', in which case you make a hole.  A very tidy hole.  Math professor here too, so the hole is nearly perfectly square.  No sloppy holes, thank you.

The suspect sender, an original VDO brand part.

The world's cleanest 'hack job' (lets face it here, most purists would cringe at such an access panel, but I get the logic and the circumstance, so no worries from me)  Look, even the edges of the hole are treated with rust inhibitor.  That is one damn clean hole. (Get your minds out of the gutter, people)

It even has a little swivel do-hickey clasp through bolted to the panel to hold the access closed.

Removed and spritzed with degreaser.  Dig that logo.  I love crap like this.  VDO.

And the new installed.

But not so fast.

The new one is even deader than the old!  At least the old flowed current and read a constant 1/4 tank at the gauge!  This replacement crap is DOA right out of the box!  CRAP!

SO, I take the old VDO and play with it a bit.  I discover that it is possible to disassemble the original. So I do.  The sender is a very simple bit of kit.  A float on a shaft, with a brass connector that runs through the float to two small wires on either side.  As the float rises and falls on the shaft, the loop for the electrical current sent to the gauge changes and that measured current change is displayed as fuel level on the gauge.

On the VDO unit, the shaft that the float travels on was very very rusty so the float was stuck solid in one place; 1/4 tank.  Probably due to moisture in the tank from modern Ethanol gas.  I cleaned the shaft, sanded it smooth, cleaned all the contacts of the sender, reassembled it and presto!  46 year old sender unit back in service.

I am quickly discovering that most if not all replacement parts are total crap, regardless of where they come from.  Even more so than was the case with my '71 VW.  Certainly the case with mechanical bits like fuel pumps and such.  Remember I had to build my own rear shift coupler too.

Fuel gauge, sorted.

Keep 'em German!

1 comment:

Steve Reed said...

Well, that stinks. Get your money back! I would have guessed that the problem wasn't the sender but something else -- good you persisted with fixing the sender.