Thread: Underseat fuel tank rubber mounts

Ive just checked my 71 WKSP rover and both tanks have 3 holes front and rear and are bolted solidly too the frames whereas my 77 ser3 SWB has the front 3 bolts on each tank solidly mounted and 2 rear bolts on each tank(located approx 1" either side of centre)rubber mounted.

Ok, the single rear rubber mount on the fuel tanks is on s3 and later only because the clamshell chassis design of the s3 allows more chassis flex, and without the rubber mounting, the possibility is there for the fuel tank to flex too much and split. S2 s2a dont have the single rubber mount due to a hell of a lot less chassis flex due to the welded box section chassis design.

Simples....

Hope this clears it up for all of you...

Cheers Rod

Swb S3 also have a welded box section - so do those have the rubber mounts?

I have just reinstalled the fuel tank in my series 3 .
It has one bolt at the rear. The bolt has a shoulder to stop the rubber mount being overtightened.
The bolt is approx 5/16 shoulder with 1/4 thread about 1 1./4 long from memory.
I used two ford stabiliser rubber bushes Mackay part number A755 and cut them in half to make them the correct size for the bolt.
The A755 bushes have a step that matches up the larger hole in the fuel tank (Fuel tank hole approx 7/16 inch.)
Please ensure you use the special extra wide washer/spacer on top of the chassis bracket as this will even the load out on the chassis.

Ian
Bittern

My 109 which is ex government (telecom ) has the dual tanks drivers side is the large long range and is mounted with tree bolts across front and two rubbers at rear the aux tank is firmly mounted with three across front and rear

Originally Posted by JDNSW

Swb S3 also have a welded box section - so do those have the rubber mounts?

Hello again from Brisbane.

As noted before, mine does. Ditto the box chassis.

Cheers,

Neil

Originally Posted by 67hardtop

Ok, the single rear rubber mount on the fuel tanks is on s3 and later only because the clamshell chassis design of the s3 allows more chassis flex, and without the rubber mounting, the possibility is there for the fuel tank to flex too much and split. S2 s2a dont have the single rubber mount due to a hell of a lot less chassis flex due to the welded box section chassis design.

Simples....

Hope this clears it up for all of you...

Cheers Rod

Ahhh Rod,, I was with ya mate,, right up until John shot that theory down
I was working with it,, sounded most plausible

So on inspection of mine last night,, it has three bolts at both ends,, no rubbers that I could see at all.

Hello again from Brisbane.

There may be an element of truth in all of the evolving theories.

One of the common criticisms of Series 3 vehicles was that their chassis were constructed of poorer quality steel than the preceding models. Supposedly due to some bean counting on the company's part and especially post the Leyland takeover.

The criticism is generally focussed on longevity, but the switch to the single rubber bushed rear bolt on the tanks might have been an engineering fix to flexing problems. Most design modifications have an engineering root and, more often than not, for good reasons.

Anyway, knowledge advances through challenge - so, that's all a hypothesis.

Pinch and a punch....

Cheers,

Neil