Starting difficulties after diesel pump o-ring change

[rustyp]

Hello there,

just changed the seals on my diesel pump (had to trim the outer edge of the seal closest to the block to get it to fit into the recess!)

When I went to start it it wouldn't. Seemed like it needed priming (my diesel filter housing doesn't have a primer pump)

Any hints and tips or will I have to get a priming bulb?

Cheers, Russ

[mikeonb4c]

I do believe it can take a fair bit of turning over to get the system filled and engine started. You might want to PM Dandywarhol before you flatten the battery as he did this job a long time back plus is top dog on Bongo mechanics, being a pro himself. Sounds dodgy having to trim one of the O rings - I'd have thought they needed to be complete and accurately shaped in order to ensure a good seal under pressure. I've not heard of that having to be done before. Hats off to you for managing the job though - I did my back in bending over the unit trying to remove the back plate.

[rustyp]

Both batteries did go flat but I have a jump-starter in the shed

O-ring was distorting as was a little too big for the hole

Will try again today

[rita]

Both batteries did go flat but I have a jump-starter in the shed

O-ring was distorting as was a little too big for the hole

Will try again today

Hi rustyp,

Sounds like you have the wrong size (profile) O rings,try a new set of the correct O rings.

[mikeonb4c]

Both batteries did go flat but I have a jump-starter in the shed

O-ring was distorting as was a little too big for the hole

Will try again today

Hi rustyp,

Sounds like you have the wrong size (profile) O rings,try a new set of the correct O rings.

From all I've read about the pressure these pumps operate at, my gut feeling is you have to 100% sure that you are fitting the right O ring. Dandywarhol briefed Lawson Diesels in Edinburgh a long time back and they will supply the correct (Bosch) ones by post (I got some from there), though I think they are a standard item as long as you know what to ask for.

[rustyp]

They are the correct Bosch ones from Bongobits (both identical), one fitted perfectly, the other was slightly too large for the recess it fits into

[mikeonb4c]

They are the correct Bosch ones from Bongobits (both identical), one fitted perfectly, the other was slightly too large for the recess it fits into

Ah! Well that stuffs that theory then

Strange that no-one has brought up this problem before