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Savagevervet
07-22-2016, 05:34 PM
Hi everyone!

I'm new to the forum, so I hope you'll bear with me, especially if I'm asking questions that have already been "asked and answered" a hundred times.

I have a 1973 ex-MOD Series II Lightweight that I purchased several years ago from a gentleman in the south of England. Having owned Rovers before, I know they're full of lovable quirks and idiosyncrasies, but I'm wondering if there isn't a "fix" for the overpowering fuel smell that comes from the tanks every time I start the vehicle or fill it up. The tanks are located under the front seats, and both have a fair accumulation of spilled fuel and grime that I'm sure dates back to the mid-1970. Moreover, there's not much of a seal between the tanks and the metal plank on which the seats sit. This was a military vehicle, after all, and isolating gas smells was not a priority of the designers.

Admittedly, I haven't taken a rag and scrubbed the accumulated gas and dirt scum off the top of the tanks. The reason is that I wasn't sure if the effort would be futile and that I wouldn't be better off replacing the tanks altogether. Has anyone ever successfully dealt with this issue? It's a no-frills vehicle designed for tough military service, and part of me feels silly for even asking the question. However, I know my wife would be pleased if we could alleviate some of the pungent gas smell. Plus, it would be much more "civilian friendly" if there was a way to make it smell less like a fuel pump.

Any suggestions from forum members who have experienced this lovable "quirk" would be greatly appreciated.

Best regards!

Savage vervet

TeriAnn
07-25-2016, 09:36 AM
Try replacing the seal on the fuel gauge sender unit. If it is a bayonet type attachment make sure the sealing ring is tight after replacing the seal. If the sender is held in place by screws, there should be a fiber washer for each screw.

SafeAirOne
07-25-2016, 10:40 PM
Are you sure it's not coming from a leaky tank selector valve?

bls72bmw
07-26-2016, 03:36 AM
I am dealing with the same issues in my 73 Civilain NAS 88" with only one tank. Its the original tank and I found out there are several seals that should be there that have corroded over the years. There is a foam seal between the tank and body that you have to drop the tank to replace. There is also a seal between the gas cap filler tube and the body. Greg at RN helped talk me through it all. I am in the process of replacing the tank and all these seals. Its a much bigger chore than it looks to be due to fitting the filler tube and the way it goes on. Greg suggested using silicone as a sliding lubricant. I have not finished the entire change yet so knce done I will post up if made a difference or not.

cedryck
07-29-2016, 08:06 AM
My tanks smell more when full, and still have a gas odor when low, seals are good, gas caps are sound.

lumpydog
07-29-2016, 08:21 AM
There are a bunch of places fuel vapor can come from.

- Sender port (uses a fiber gasket as has been mentioned)
- Fuel pickup tube (cork gasket)
- Fuel filler neck/hose where it connects to the tank (hose clamp)
- Fuel tank rubber vent tube where it connects to the tank (hose clamp)
- Fuel filler neck/hose where it connects to the gas cap fitting (hose clamp)
- Fuel tank rubber vent tube where it connects to the gas cap fitting (hose clamp)
- Foam seal and rubber gasket that sandwich between the tank and the seat box
- The gas cap itself (rubber seal). But is meant/designed to vent on some Series trucks.
- Any interconnect in the fuel lines
- The fuel pump and bowl
- The carb

If you're smelling fuel in the cabin, I'd check the 4 hose clamps first as they are all inside the cabin. The first two are right behind the passenger seat and the latter two are behind a cover situated behind the passenger seat bulkhead to hide the rubber fuel filler neck. Then check the foam seal between the tank and the beatbox.

[Edit = just realized you mentioned yours is a lightweight - pretty sure above (describing an SWB 88) applies still.]

Les Parker
07-29-2016, 12:50 PM
Remember this is an EX-MOD, thus no filler neck or vent hoses. I would check the filler cap, most had a brass vent valve, also make sure that is not blocked and that there is a seal around the filler caps themselves.

neil.peru
07-29-2016, 06:18 PM
Hello everyone;

I had/have similar problems on my two SIIA,SW trucks (19gal tank on back).

One of them (1970) has an issue of overflowing fuel when tank is filled full; smell is very noticeable but once it is running it disappears, even with a full tank.

The other one (1969) has also fuel odor because the tank has a crack on it; I can see bottom of tank wet of fuel and recently saw fuel dropping slowly after I filled the tank half full; so I am running it now with a 1/4 tank mostly and spill/odor dissapeared (tank is going to a shop for repair next week).

I agree also with the previous posts; a bad seal on oppenings for draw tube, fuel sender unit or anything that comes in/out of the tank can potentially be a source of fuel odor.

Best regards;
Neil