New fuel sender unit
The fuel gauge in the Pootle wasn’t working when we bought it. After buying the van we drove back up from Milton Keynes to Glasgow, guestimating about 25p per mile. At each fuel stop we hoped to gauge how much we would need to keep us going and thought we were doing ok til we ran out of petrol just 30 miles from home on the motorway. The fuel gauge would be one of the jobs Raymond would look at before the others on the (very long) list.
We took the van down to see Greg at Bus Stop Ecosse. Greg tested the sender unit and, although he thought it wasn’t great, it would maybe be up to the job. He determined the problem was the gauge by using a test dashboard he had lying around and replaced the gauge. This seemed to work.
Next big trip in the van and we filled the tank right up. The needle peaked above the full mark and never dropped til we ran out of fuel in Dundee. It then worked intermittently for the next few trips. Oh the joys of owning a VW! With a dodgy sender unit, we were back to guestimating how much we would need for each trip. By this time, Raymond was loving the VW Heritage catalogue and ordered up a new sender unit.
To replace the fuel sender on this bus you have to either gain access to the fuel tank by taking out the engine and the bulkhead at the rear of the engine compartment. Or, as many people do, cut a small hole about 15cm square in the top of the engine compartment at the back of the van. If you do decide to cut this here you will need to patch it back up after finishing the job or the van will stink of petrol. Our van obviously had an issue with this before we bought it as it already had the hole cut so Raymond had access to the top of the fuel tank where the sender unit is attached.
The top plate of the sender unit is circular with two cables attached to it; one that comes from the sender unit, the other goes to ground. When you take it out, pay attention which is which and mark if necessary. At this point it’s a good opportunity to test if the gauge works. To do this, remove the cable from the centre of the sender unit and touch it with the terminal attached to the cable that goes to ground. This should make the petrol gauge on the dash go to the full position. If not, you will need to replace that too.
With the cables removed, the sender unit can be taken out. Raymond used a set of large gland pliers to grab the sender unit and just under a quarter turn anti clockwise to release the unit. The unit and the floating rod attached then came out.
At this point you could test the unit. A page detailing how to do this job will appear soon.
After attaching both cables move the float arm from one position all the way through to the other. Check how the fuel gauge reads this as the resistance of the new unit might not be the same as the old sender unit. Luckily when Raymond did this the Pootle’s fuel tank was nearly empty, meaning that it would give an accurate reading when it ran out of fuel. It took a bit of patience to do this as the new sender unit was in and out of the tank a few times before getting the setup just right. The corrections were done by slightly bending the metal rod holding the float so that the needle on the gauge was pointing to the bottom of the red reserve area when the float was touching the bottom of the tank. At the worst point, the gauge on the Pootle was showing about a cm under the bottom of the red reserve line when the float was touching the bottom of the tank.
Hopefully you will be a bit luckier. Then the unit went into the tank, positioned with the float rod at 2 oclock when facing the rear of the van. This bit was a bit fiddly but once located, just under a quarter turn clockwise secured it in place.
Then both cables on the sender unit were reconnected and the hole was patched up. If you’re doing this, get a piece cut from an existing engine bay bulkhead so it is corrugated and fits easily. Or it could be fabricated from a bit of thin sheet metal. Then screw in using self tapping screws and go round the edge with a lot of silicone. Or of course it could be welded on!