Fuel Guage Miss-information unit
Once I can live with but twice is too much :evil: :evil:
Two weeks ago I was tooling along the A38 (60mph!!!) thinking how well the G was doing on the last tank of veggi...sorry Diesel when the G started stuttering and then went very quite! as I coasted along looking for a flat bit of grass (no hard shoulder) to pull up on I tapped the gauge and the needle dropped from 1/4 to Zero. Any way ended up in a very dangerous spot, but a passing AA man towed me to a layby and flogged me 10ltrs of juice. Nice man, very nice man... especialy as I'm with the Green Flag lot :twisted: :twisted: .
Anyway Lesson learnt thinks I :D . Since then a regular tap of the gauge has resulted in an instant re-concilliation of Fuel level. Untill today. This time (she picks her time!) :evil: :evil: I'm in a narrow cutting on a fast two lane road with no pullover spots. Fist pounding on gauge still tells me I'm over 1/4 full. Manage to swing in after a bridge and parked on the bank "how did you get it there mate?" was the comment when the Chaps turned up to rescue me (2 lorries, 1 to block the road and the other had a big boy winch on it " G wagen Sir? that's a big heavy thing isn't it?" went the phone call). Hats off to Green Flag and Plymouth Recovery Service first class :D :D :D .
So if you've managed to stay with my story.......my question......any ideas where to start on the gauge system? I know where it is and I have diagrams. Any help welcome. :) :) Would I be right in suspecting an earthing problem?
Best thing to do is strip down the fuel sender unit and carefully clean out the internals of the sender unit. Over time, algae can develop and build up, internally, clogging up the drain hole and body of the mucus type membrane at the base will not allow a plastic float to reach the bottom to allow an accurate reading.
It is because of this, also, you do not get your reserve fuel or low fuel warning light coming on.
I have experienced also, that from a completely empty tank, at least 10 liters of fuel needs to be replenished before a start up.
Do be very careful working with a dismantled sender unit, the sensor wire in the tube of the sender is hair line thin. If you break it and cannot rejoin it, you are looking at a new sender, that about £120. (I expect that to be grossly, out dated by now)
It would be adviseable to renew the seal, for what it costs. It is possible to reuse the old seal provided it has not hardened, but you will only come to know that when you remove the fuel sender unit.
One other point to consider, depending upon the condition of the sender unit body, if it is rusty and weakened, it may not stand the reqour of un screwing without a proper tool, so much so the fuel sender will have to be replaced. when buying the new sender unit, I think, comes with a new seal, double check with the parts dealer.
I suppose you will want to know how remove the sender unit without a proper tool? Using a blunt chisel head and hammer, tap to unwind, butting against knotches surrounding the sender unit.
Rakesh,
You've got me in sitches! Not knowing a proper tool was required I would probaly have chosen the same specialist kit you've recomended. I'll tackle the job later in the week when my zaffies road legal again( forgot 3year old cars needed a MOT..... DOH!).
Cheers
Grendle
This is what the trip meter was designed for... reset every time you fill up and monitor the miles/fill .. far easier than fighting for a hard shoulder :(
As said .. sender will be issue as reserve light has not come on.. watch out when you pull it out that you do not knock the strainer assembly off the bottom; it is only held on by a rubber lip and it seems the corrigations are slightly larger than the hole in the top of the tank. Mine had a spare one floating around inside the tank from a previous attempt.
I take the Trip meter point. With my Zaffie I use everyday (these are all poor in the last 1/4 tank). I know I get 36MPG general or close to 50 MPG on a Run so the Trip meters fine. I have not got to grips with the G's MPG yet as its used off road, tows my boat and runs errands so it's very variable. Mind you I can not believe its in the high 20's as some claim! Spoke to the previous owner last night and he told me that the low fuel sensor is also disconected so I guess a througher service is in order.
Thanks for the strainer tip I'll be carefull.
Grendle
Always carry a few litres of fuel spare aswell, I have learnt my lesson with this we have a Dodge Ram that is very thirsty and I ran out within 100 metres of a garage completely blocking the road, had to buy a can walk back, apologise to angry motorists and then drive 100 metres to fill up, very costly :cry:
Yep I have 5ltrs of Asda,s best biofuel in the back now.
Cheers
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Rakesh you are a star Sir. Do I need a new Gaskit available before I start ?