Think I've got a tank leak

My mpg has recently gone down from 20mpg to around 8mpg. I've checked the carb for overfuelling and replaced needle valve and gasket and checked all fuel lines. Engine is running at correct mixture (checked with AFR meter).

So last candidate is fuel tank, I'm going to try and get up to the garage when its light enough to have a good clean up round the tank to see if I can spot where/if its leaking. Rolling around in the slush trying to work it out is not fun!

To keep me up and running I've bought some "Granville petro patch" - does anyone know if the stuff works or is it a bit ****e.

In the medium term, when the weather warms up I'm going to take the tank off and give it a good refurb, paint and a dose of POR15 tank liner stuff. Is it possible to get the tank out of a SWB without removing the seat box or is it a body off job?

Cheers

D

Comes out of a SWB series 3 without taking body of , think 1's and 2's are the same 109's are different.
Mine occasionaly leaks diesel from pick up pipe flanges on the top end up stripping and re sealing with Stag.
Mate used to seal his petrol tank with Araldite but thats probably environmentally friendly now so less likely to work.

Petro patch is a bit hit and miss. Usually find it cheaper to use bit of tin, araldite and duct tape.
Tank liner works well if you follow the instructions.

Thanks lads,

The petro patch is just to keep me going if I find there is a hole...I had another look and can't see or smell anything but the petrol must be going somewhere. I need to set up a camera I wouldn't put it past someone syphoning it!

surprisingly heavy when balanced on your knees while you are on your back Dom...prepare to do a lot of swearing

Im pretty sure the tank just drops down. I remember struggling to support it from underneath when fitting mine anyway

chemical metal and 1p or 2p.

that way you are adding value

Thanks lads, I'll maybe drop it out at the weekend if its a simple job...it probably isn't its probably rusted solid and unshiftable...

Well I've had a good look round and there's nothing leaking - tank looks ok, the dose of red oxide I gave it a couple of years ago could do with another coat though.

I now think its not the tank but that there's something up with the front axle. I usually drive around with the FWH's disengaged but with the weather over the past month I've left them on. I tried turning them off the other day and the improvement was huge.

So, this aft, I had a look round and swapped the diff oil and gave the swivels a dose. There was some water in the diff oil but no more than usual and everything felt nice and free so I'm not sure why its suddenly started making such a big difference. It used to come out at 1-2mpg before when I measured it...You can really feel it with FWH's off it drives like normal, with them on you need to be in 3rd for hills that I can normally do in 4th+overdrive!

4wd is definitely working ok, just been out on the snow and ice and all is well...

Well, now I feel like a proper donkey. I've sussed the problem - when on the motorway this aft I noticed that the odometer and trip counter were stopping and starting. Looks like its time to send off that speedo and get it serviced!

Try changing the cable first.....

Cable is ok as the speed reads solid enough. I suspect the little plastic arm that clicks the number tumblers round is loose or worn. I want a recalibrated one anyway as I've swapped the diffs

Cheers

D

Ok