Bosch Diesel Injection Pump Disassembly

Unread post by **KennyW** » 11 Feb 2010, 15:29

Hi Jim and Mike,

I've corrected my error with the camplate and rebuild the original pump.

Carried out bench test as suggested and the Lhm fluid is firing about 4' to 6' across the garage

, therefore i assume the pump is working mechanically.

I remove the plunger from the stop solenoid to help.

Out of interest how did you turn the sprocket as after doing it by hand I thought why not use my elecrtical drill

Jim, How did you remove the majority of the LHM from the pump

If the same problem appears, it must be electrical

Kenny

Unread post by **CitroJim** » 11 Feb 2010, 16:50

Excellent work Kenny

I leave the LHM in there. It's combustible (if a little smoky) and it will soon get burned.....

A good prime on the priming bulb will soon mix it with diesel anyway.

Eager to learn how it goes...

Unread post by **KennyW** » 15 Feb 2010, 21:34

I have started to remove the pump but prior to doing so I thought I would confirm supplies were going to through the 3 plugs on the pump.

The supply for the blue plug is 5 volts which is No 1 from the ECU and No 3 on the plug.

The supply on the brown plug comes direct from the battery via a fuse in the engine compartment and through the relay 12 Volts.

The separate feed for the Solenoid is also 12 volts.

I'll see what is what with this other pump tomorrow.

But SWMBO's car is going for MOT

Kenny

Unread post by **KennyW** » 17 Feb 2010, 20:06

Well the second pump is also working and now fitted to the car. tried starting agian without success

.
But I think the problem is air in the injector pipes ie the pipes from the pump to the injectors.
Jim, Mike and anybody else, would fill up the pipes with diesel help in starting the car

Kenny

Xaccers · Unread post by **Xaccers** » 17 Feb 2010, 20:51

Crack the nuts off the pipes at the injectors, wrap them in plenty of rag as the diesel will come out of them at high pressure, high enough to cut you from what I've heard.
Turn the engine over until the rags are showing diesel on them.

Unread post by **KennyW** » 28 Feb 2010, 14:22

Hi all,

Finally I got the car going and it runs ok, but the same problem from a year ago is still there.

It is not starting whether hot or cold

I now firmly believe it is something electrical. I am thinking to start from the beginning again and get a hold of an 2nd hand iginiton barrel and swap it over. This was the original problem.

My other thought has the ECU developed a problem.

Kenny

xmexclusive · Unread post by **xmexclusive** » 28 Feb 2010, 17:51

You can check out the effect of a replacement ignition switch easily without removing the old one. Just unplug the three leads and substitute the new switch, loop the new wires and switch over the top of the steering column cover. Tape in place if you want to drive like that. The old switch now just works the mechanical steering lock so needs a turned key in it. The temporary switch will provide all the electrical functions.
The ignition switch that Citroen used from 1993 onwards has SIMPLEX marked around the key way on the chrome faceplate. The switch contacts in these deteriate significantly with even moderate use. Secondhand ones are often as bad as the defective one they replace. Hence my suggestion above to try the replacement in service before you go to the effort of threading it into the steering column.
Since that time Citroen changed to using VALEO ignition switches (marked in the same way) and these have simpler, more robust electrical contacts. The relacement switches that GSF supply for the XM and Xantia are normally to this later Valeo design.

John

Unread post by **KennyW** » 28 Feb 2010, 18:18

Thanks John for your reply,

My original ignition barrel did collapse and I replaced it with a complete igniton set and this is when my troubles started

(I think the replacement is a valeo .)

I did find some sod tried to steal same by hot wiring and cut 2 wires which put back together.

I am trying to fathom out where my problem lies

Kenny

Unread post by **CitroJim** » 28 Feb 2010, 19:47

KennyW wrote: My other thought has the ECU developed a problem.

If the ECU is duff/not properly powered Kenny, two things will happen. The glowplug controller will stop working and the pump will be forced to fully retarded timing. Both will make the engine jolly hard to start and if fully retarded it'll run very roughly. It will not make the engine impossible to start though and it won't cut fuel.

Also, if the ECU is dead, the tacho will not work and the EM light will not illuminate at ignition-on...

Unread post by **KennyW** » 28 Feb 2010, 21:53

Hi Jim and all,

How do you know if the glow plug controller is not working

What symptoms would the car have when running with the pump fully retarded.

Here is what I have observed, the glow plug light on the dash does light up and goes out after a short period of time.

The EM does light when I switch the igniton on

Hence, I'm thinking of a partially faulty ECU

Latest is it is not even starting when allowed to roll down hill.

But I think I had removed the transponder from the igntion switch earlier but placed it back on when I tried the push start.

I think mechanically it is going but needs some fine tuning.

Is it possible to confuse the ECU with various changes I have made.

Sorry for all the questions but I am slowly losing patience and suspected a faulty pump which would appear to ahve not been the case.

Kenny

Unread post by **CitroJim** » 28 Feb 2010, 22:27

Kenny,

an IDI diesel, as the 1.9TD is, will be almost impossible to start if the glowplugs do not do their job properly. You say the light comes on and goes off after a short while. How short?

To really test, you need either a meter or test lamp on the glowplugs themselves and see that they are active for at least 30s. Ensure that at least 11V is reaching them. They should be active for a while even after the light goes off. After starting, the glowplugs should come back on again (post heating) and remain on until either the engine revs above one third throttle or the coolant reaches 60 degrees.

A fully retarded engine will run very softly and quietly with smoke. It'll develop little power as most of the diesel is ejected through the exhaust port before being burned. It'll be also very difficult to start and will not idle well, if at all.

An advanced engine will run very noisily and knock and tinkle, sounding a bit like a petrol engine that's pinking badly. An over advanced diesel engine is easy to start as when cold the ECU deliberately adds advance to aid starting. Fully mechanical Lucas and Bosch pumps have an electrovalve to invoke cold-start advance. This gives the cold diesel longer to get it's act together and start burning in a cold engine.

Diesel timing is very critical. Much more critical than a petrol engine.

The ECU has no relationship to the immobiliser at all so that can be discounted.

A Lexia session is needed now to check the ECU operation.

Unread post by **KennyW** » 01 Mar 2010, 01:29

Thanks for the reply Jim,

I will investigate further and conduct tests but I did check the voltage at the Glow plugs it was almost 12V's. I did not check How long for.

Does the voltage stay at 11-12 volts or gradually lower over the length of time. I seem to recall a reduction in the voltage with time.

I will report back.

Kenny

Unread post by **CitroJim** » 01 Mar 2010, 22:34

Yes, the voltage will fall a little with time Kenny as the current drain drops batter voltage a little.

Glowplugs take a lot of current, certainly around about 50amps and hence why diesels need a good battery.

Unread post by **KennyW** » 04 Mar 2010, 20:30

John,

Is the GSF part No 925PC0020 correct as I believe it may still be the problem.

My reasons are as follows, I drive diesels at my work obivously when starting all the lights are displayed and on turning the ignition to start the car the lights stay on and then switch at different times once the vehicle is running.

When I attempt to start my car the lights all go out at once hence my suspicions.

Any thoughts

Kenny

P.S. I have 4 days off so I am going to check all the electrics

Unread post by **KennyW** » 05 Mar 2010, 18:01

Hi all,

Ichecked the voltage at the glow plug and 12 volts which dropped at little and then the relay switched the glowplugs off about 10 seconds later.

This would suggest the glowplug circuit is operating correctly.

I checked the supply from the relay into the ECU at points 16 and 33 again 12 volts.

I had already checked the supply to the stop solenoid 12v's and the in supplies for the brown and blue plugs again 12 volts.

I also checked my repair at the ignition barrel in case it was earthing but I had wrapped insulating tape around the connections.

So mechanically the pump is injecting fuel as per the bench test and I had it running last weekend.

I think I have checked all the electrical points.

My conclusion is when I put the replacement pump on the engine, the pump is retarded and the injection phase is too late to start the engine.

Any thoughts would be appreciated.

Kenny