Diamond T 969 fuel cap

[jack neville]

The photos above are of a cap from a 969 wrecker owned by a friend of mine. Can you post a picture of the cap you have please Maurice.?

[lendlease]

If the truck is early production with "civilian" type gauges, then it would most certainly have the small 2" fuel caps. The larger 4" caps were from 1943 on....

[tankbarrell]

I agree with Maurice, that cap is from a British bike originally and fits a plain tube. As far as I know, all US necks have some sort of bayonet type fitting.

[jack neville]

This is the fuel tank in the truck.

[jack neville]

If it is not the correct cap does anyone have a picture of one? It screwed in to my mates fuel neck nice and tight so it certainly fitted properly.

[Maurice Donckers]

I will take a picture as soon as I am there .
The Diamond 980 981 kept a small filler neck till the end .

[Maurice Donckers]

one on an early civy dash Diamond , and onother NOS one

[jack neville]

Originally Posted by lendlease

If the truck is early production with "civilian" type gauges, then it would most certainly have the small 2" fuel caps. The larger 4" caps were from 1943 on....

The filler neck measures 75mm o/s diameter.

[jack neville]

I received the cap from Maurice and it is to fit a 2 inch neck. No good for my truck. The neck on my tank is 3 "/75mm. I believe my tank is original, (the bottom is rusted out) and it is identical to an early 969 of John Belfield's. Still looking for answers. And a cap. (PM sent Maurice.)

[Maurice Donckers]

The fuel tank neck must have been changed at one time , the Americans only had 3 sizes , 2 fuel cap sizes , all early ones were 2", 980/981 stayed that way , and the bigger one , the 3rd was a radiator cap size .
looked at the Matchles in our collection , and that has a 75mm neck with your cap on .

[Maurice Donckers]

Last picture shows Matchles tank cap.

[jack neville]

Thanks Maurice. Just for interest can you get a close up of the inside of the Matchless cap and the neck. I had another look at my tank and you can see from the above picture that the neck on mine is at the edge of the tank pointing out on an angle and not on the top flat part of the tank. I cant see anywhere where the 2" neck would have been removed and the hole blanked off, but I haven't removed the tank either as yet so I don't know what else could be revealed under the tank guard/step panel.