ScarboroughSeadog

Howdy folks- my grandfather brought this back from WW2. He said it was from a glider in Sicily. That’s all I know- see the markings. Is it from a Horsa? Or an American glider? Is it from a gunsight? My grandfather is long gone and my Dad is trying to research the gyroscope, without much luck. Grateful for any thoughts! Thanks.

Ruxy- The TB1114-001W senders as now produced are a multi-fit part, which (correctly) span a variety of vehicle set ups from mine (older, less common, military specific) to a range of other classic civvy landrovers (which do have the red mark on the gauge). It would make sense if they are calibrated to by far the most common application (ie the latter). Fortunately I had a repairable 40 year old TB1114-001W which works perfectly- problem solved. Thanks for your help and advice.

I have to say…..I think you’ve nailed it! These senders cover a few different set ups, and hence supply to different gauge decals etc. My particular (dated, less common) set up is an anomaly as far as these senders go. I suspect your explanation will save a fair bit of head scratching for many with this issue- I bet you’re right!

Always good to finish these things off with a conclusion: replaced a faulty fuel gauge, replaced a faulty Lucas switch. All now working perfectly but there is an interesting issue with the senders. I have 3 senders marked TB1114-001W. This is the correct part number. One is brand new, one is say 10 years old, one is say 40 years old. Only the 40 year old one reads correctly (ie empty at empty). The other two newer ones read 1/8th at empty. I can only think the more modern parts have a different resistance scale? Fortunately with a repair made to a snapped spade connection I was able to use the original 40 year old part and all is working perfectly. Bit of a mystery though.

Thanks Ruxy- will try and decipher all this when back in civilisation (away working in the north of Scotland at the moment). My fuel gauge is mounted at 6 o’clock- as you say, as per a late model fitting. Also have the late model oil and temp gauges and transmitters you describe. Haven’t had much time to look at the lightweight, but have now replaced both Lucas switches and have one tank reading perfectly. One tank still not registering empty but suspect that is it’s sender- will replace and see. Expecting that will solve the problem, but will see! Will post a conclusion and findings as soon as I can- but don’t expect that that will be in the next few days.

Just double checking that the Lucas switches are NC? So the circuit is made when the nipple is NOT depressed/activated? If the nipple is depressed by the tap, that breaks the circuit and therefore stops any reading from the tank connected to that switch, correct? I'm thinking if one switch is faulty and remains closed (or partially closed) when activated, that would mean both switches (tanks) are closed (reading) at the same time, which might explain why the gauge reads 1/8 when the tank it should be reading is empty? Does that all make sense? Feels like a bit of a eureka moment, but not in the shed until Sunday eve.....

That said, I’ve owned mine for nearly 25 years and until recently the fuel gauge readings have been spot on. The problem I’ve got is resolvable- just need to figure out the fault.

Thought of that- but the 1/8 reading is at absolute minimum on the sender arm (bent or not), so doesn’t work.

It would be really useful to have a 'print thread' option for reference purposes, which prints the text in a suitable (concise) format without all the banners etc. Is that possible? They have just that on the Lightweight Forum and its very helpful.

New Lucas switch about £30. Mine are over 40 years old so don't mind renewing speculatively. Chain spray probably good preventative idea.

Yes- PRC1789 and 90560612 fitted. Have cleaned the various connections. I'm going to replace the second Lucas switch on the changeover tap. This should be NC (normally closed), but if it has deteriorated and is remaining partially open when not activated, I wonder if that could explain my bogus reading......

Yes, I have a single ammeter on the shunt box- which is located in the rear tub behind the drivers seat. Correct, contract FVE22A/87. First entry on the VHC is 27/11/79. Chassis 95105646A.

Understood- that's the sender I have.

Thanks Clive- my cluster is a later part I think. The gauge fits directly into a common cluster housing.

Thanks- yes correct fuel gauge is PRC1789. It's FFR 20HF63......