Diesel Pump - What goes in this hole?

[Diplomat]

Whilst planning a change of "O" rings and having a good look round for leaks, I have come across a tapped (M 12?) hole under the pump.

It is about 5 cm to the rear of and slightly below the offside dome cover (of "O" ring fame) and goes vertically up into the pump body. It is difficult to see or photograph without a mirror.

What is this for and shouldn't there be something screwed into it?

There is a slight drip of fuel there but I am not sure if this is coming out of the hole or just running down from elsewhere and collecting there as the lowest point on the casing.

Any ideas? The exploded diagram shows a hint of it being there but no sign of a bolt or cap. It seems a bit odd that it is open.

I have put a short bolt in there with a fibre washer to see if the drip stops. The engine hasn't stopped yet!


Frank

[Diplomat]

Well so far this has had 84 lookups - the post, not the hole!

Yet no one is any the wiser. I know I didn't take a photo but this is most unlike the usually knowledgeable Bongo fraternity.

Hands up who knows where the pump is, what it looks like, which side is it on, how do you unclip the engine cover?

Perhaps your own pump has either got a mistery hole or something blocking the hole?


Waiting with vegetable oil bated breath,

Frank

[missfixit70]

I was going to go & have a look for you, but haven't had a chance, try & have a look tomorrow if it isn't raining & I get a chance

[Diplomat]

You'll need a small mirror to see upwards, Kirsty.

If I can get enough light I will take a photo.

It passed the MOT during the week and the pump weep was not noticed/remarked on.

Drop links and anti roll bushes flagged up for next time.

Simon, who does my MOTs told me that a Freda which comes in regularly keeps cracking the rear bush clamps.

Frank

[missfixit70]

Just had a look & a poke, I seem to have the same threaded hole with nowt in it, I'd be wary of putting a seal where it doesn't appear to be fitted originally, could just be they've both dropped out of course, anyone want to check & make it 3?

[Diplomat]

Thanks for looking, Kirsty. It looks like the rain stopped in Dorset round about lunchtime!http://www.paulnic.com/weather/index.htm(Recent NOAAs)

It crossed my mind that the hole gives access to something that is adjustable, cf. on my domestic boiler the gas flow and pilot light adjusters are recessed with screw in covers.

Because the mystery hole is upward facing, anything screwed in there could quite feasibly fall out.

I haven't found any plugs lying in the engine tray.

Inserting a short bolt with a fibre washer has not affected the performance, as far as I can tell. I only did this to lessen the risk of failing the MOT through dripping fuel. Lucky we're not talking petrol here!


Frank