Bosch Diesel Injection Pump Disassembly

Post by **KennyW** » 24 Dec 2009, 17:11

Hi Mike,

Here is my snow Xantia awating completion 8)

Kenny

Post by **KennyW** » 04 Feb 2010, 22:32

Hi Mike and Jim,

I have identified a mistake i made when rebuilding my pump.

On the cam plate there is a pin which shuold be in aligned with the woodruff key on the drive shaft and I am sure it is out of sync by 90 degrees.

I'm sure this would cause a problem

Would this cause the problems of no fuel to the injectors or reduce it

I will check my pump soon as possible as i am removing it from the car again.

I have a 2nd hand replacement.

I will let you how i get on.

Kenny

MikeT · Post by **MikeT** » 05 Feb 2010, 12:54

Hi Kenny, sorry to read you're still having problems with this pump.

Yes, you can align the plunger assembly 180 degrees off but I was certain you'd already eliminated that?... either way, it won't cause a restriction to fuelling, it will just put the timing out by the same angle.

Post by **CitroJim** » 05 Feb 2010, 15:06

Ahh yes, It might because the filling and pumping strokes of the HP pump would be out of kilter and might result in no output.

Did you see my post (in the Citroen section I think) on how to crudely bench test a pump after a rebuild?

I've copied it here for completeness:

You can bench test a pump by arranging a small tankful of LHM (or Hydraflush or veg.oil but NEVER diesel) that will supply the pump. Apply voltage to the stop solenoid and spin the pump over by hand using a spanner on the sprocket nut.

I use a big funnel on the end of a length of clear hose as my test fuel supply tank.

Spin it until "fuel" starts to flow out of the return line (thus showing the lift pump is working and delivering transfer pressure) and keep turning it. You should see jets of fuel spit from the four delivery valves in turn as you keep rotating the pump. A good pump will "fire" fuel about four feet Aim the delivery valves at a wall!

NEVER use diesel for this sort of test

As you've had it all apart once, there is nothing to loose, but everything to gain, in going over it again until you find the basic fault and it works on the bench.

My test is crude but it does basically show if the pump is fundamentally functional.

Good luck Kenny, second time lucky

Post by **KennyW** » 05 Feb 2010, 20:34

HI Mike and Jim,

I put on the 2nd hand pump I acquired but the same problem. Not a drop of fuel coming to the injectors.

Is there anything which might affect the delivery ie relays or something.

Its strange that the same problem has appeared with a different pump.

Any thoughts.

Kenny

Post by **CitroJim** » 05 Feb 2010, 21:33

Well, that is odd Kenny...

If you can, unscrew the stop solenoid and see if fuel issues from there when you spin the engine over.

It's not unknown for secondhand pumps of unknown provenience to be so well gummed up with stale fuel that the delivery sleeve gets stuck.

Where did you source the pump from Kenny and how long had it been out of use?

Post by **KennyW** » 06 Feb 2010, 20:47

Hi Jim,

I sourced the pump from a specialist scrappie in Ranskill, Nottinghamshire who are french car specialists.

It is the exact pump number as my original and would appear to be built about a month apart.

Unfortunately I don't know how long it has been off the Xantia.

As you can guess I am at a loss in figuring out what the problem is.

Is there anything which I can do to lubricate the pump if it sticky

Kenny

Post by **CitroJim** » 06 Feb 2010, 21:06

KennyW wrote: Is there anything which I can do to lubricate the pump if it sticky

Not really Kenny

To give you an idea, here is a couple of shots of a pump that had been idle for a year or two..

The second picture shows the lift pump vanes totally gummed up. This pump also had a stuck transfer pressure regulator.

What you see is not rust and the pump in question cleaned up a treat but it is necessary to strip it completely.

If the pump was used for veg, you have another problem as the old veg turns rancid and very sticky indeed. Like the outside of a well used chip pan...

Post by **KennyW** » 06 Feb 2010, 21:50

Hi Jim and Mike,

Thanks for the reply, Okay from your photos my original pump is clean,the vanes in the lift pump seem fine.

It looks like another stripe down and rebuilld of the original to see what problems there are.

The other option is take this pump to the speacialist in Auld reekie and get them to do the work

Are there any static tests which can be done to check alignment, positioning of the various pieces of the pump.

Kenny

Post by **CitroJim** » 06 Feb 2010, 22:22

KennyW wrote: Are there any static tests which can be done to check alignment, positioning of the various pieces of the pump.

As far as I recall, as it's been a while since I've stripped a Bosch, it will only reassemble one way and therefore it will be all in alignment. I'll have to dig one out I have in bits and have a check but I'm pretty sure it's not possible to reassemble it wrongly...

Bench testing is the best way to basically prove it'll work before returning it to the car...

Post by **KennyW** » 06 Feb 2010, 22:35

Okay, its strip the pump time and rebuild and carry out your bench test.

I'll do that in the next few days.

Luckily, I have spare parts now for the fuel in and out

If I were to dsimantle the pump I bought, what would be the best cleaning method/fluid.

Kenny

Post by **CitroJim** » 07 Feb 2010, 09:31

KennyW wrote: If I were to dsimantle the pump I bought, what would be the best cleaning method/fluid.

I use white spirit and compressed air for the initial clean Kenny and follow it up with carb (or brake) cleaner if necessary.

As a reassembly lubricant I use LHM or if I have some, filtered used hydraflush... This is also a good test oil when bench testing a pump.

Post by **KennyW** » 07 Feb 2010, 20:56

Hi Jim and Mike,

I'll take a look at the original pump first and give it the bench test and see what happens.

Something I was thinking about from when the troubles first started, originally the ignition barrel played up and required replacing whilst the vehicle was off the road and parked in the driveway some kind person decided to try and drive it away by hot wiring same. I just fitted the wires together and that was that.
Could that have caused any problems and still be part of the problem now.
Likewise is it wise to remove the transponder on the ignition barrel as what good is it doing now with the immob immob'd.

Kenny

Post by **KennyW** » 10 Feb 2010, 20:17

Hi Jim and Mike,

What effect would the green injector supply relay have on the injectors if it was not working

Kenny

Post by **KennyW** » 11 Feb 2010, 12:50

Re my last post, I thinkI have identified the use of the green relay as part of the Air con setup possibly the compressor cutoff relay.

Kenny