dag019

Well-Known Member
My fuel pump has decided it does want to have fuel on the inside any more. I appear to be pumping fuel out of the cover circled below. Is this something that I can repair myself or is this a terminal failure and I need to send it off for rebuild.

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Have a look at dieselinjectionpumps.co.uk Parts and information/diagrams available.
I think that cover is for the pump advance mechanism, a spring/plunger is in there. Cover has a gasket or O ring to seal.
I am no expert on diesel pumps but parts/info from this firm has helped me repair both inline and rotary pumps.
 
I watched a video on that not so long ago. There is some sort of mod you can do also if you feel inclined to do so.
Think that is the kit, what it does I can't remember but apart from that it looks like it's just an o-ring you need.
 
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I had mine repaired by a local diesel specialist in January. It can be done yourself but I initially thought the pump was needing replacement, hence getting it done instead of doing it myself.
 
Yes easy repair just O ring. The kit is boost ring it adds spacers to make the plunger engage earlier and easier therefore quicker to get fuel. Doesn't make it go faster.
 
Boost ring alters the advance timing ever so slightly, allowing fuel to burn better at high revs, supposedly increasing power at the top end.
 
Have a look at dieselinjectionpumps.co.uk Parts and information/diagrams available.
I think that cover is for the pump advance mechanism, a spring/plunger is in there. Cover has a gasket or O ring to seal.
I am no expert on diesel pumps but parts/info from this firm has helped me repair both inline and rotary pumps.

Remove the 2 screws & replace the O ring…
Yep I know how much diesel they loose as it’s happened to me.
(Think I turned the o ring over to get me home)y
Nothing will fall out

Many thanks. Not something I am going to be able to fix in the work car park. But an easy fix once I am home and have ordered the correct o-rings. Much better than being a castrophic failure inside the pump! Will just be an expensive and un-motorbike friendly drive home along the motorway!
 
Yes easy repair just O ring. The kit is boost ring it adds spacers to make the plunger engage earlier and easier therefore quicker to get fuel. Doesn't make it go faster.

Boost ring alters the advance timing ever so slightly, allowing fuel to burn better at high revs, supposedly increasing power at the top end.

Is a boost ring worth the effort? I have heard of it before but have no expiriance either way.
 
Is a boost ring worth the effort? I have heard of it before but have no expiriance either way.
I’d say the boost pin makes more difference,
It’s like most tuning things, it’s a game of diminishing returns. I’ve a turner performance head with turbo technics vnt turbo, so the extra fuelling is required to get the best from the other mods.
The defender is a lot nicer to drive now, easily keeping up with traffic and doesn’t smoke anywhere like the ones I’ve seen who just tune the pump.
 
Remove the 2 screws & replace the O ring…
Yep I know how much diesel they loose as it’s happened to me.
(Think I turned the o ring over to get me home)
Nothing will fall out
May have got the wrong side cover looks to be the cover furthest form the engine rather than the one on thw inside. Have managed to get some pics of it running below. Do we think the stream of fuel is coming out the bottom side of the cover or from somewhere else?

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Am I right in thinking this cover has nothing behind it and again is just an o-ring to seal? Looking at the diagram here (LINK) that looks to be the case? Just need to work out a part number or size for the correct o-ring (number 36)

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You got the pic there don't need to ask but always good to if unsure. Both sides don't have much in them that immediately will fall out. Yes O ring is logical leak, I would change O rings both sides and have a spare.
 
You got the pic there don't need to ask but always good to if unsure. Both sides don't have much in them that immediately will fall out. Yes O ring is logical leak, I would change O rings both sides and have a spare.
Do you know the sizes or part numbers? I can only find them as part of a full seal kit!

The reason for asking to confirm is this picture on the seal kit page (same website LINK) shows things on both that I dont seem to have on my pump and that the o-ring is the same part which is not the case on the pic above.

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Nope but same size on all the pumps I've done. Sorry I haven't got any here to look at. The size is easy to find out. Just take out and measure. From memory it's the standard thickness not fat thicker O rings...but I could be wrong. Call or email Bosch and ask tomorrow. I will see if I still have there number.
 

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