406 2.1 now with bosch pump

[PC2CV]

A bit of a late update, but i went back to uni to do a masters the car sat most of 2023 in the shed, got back to it about a month or so ago and found a chap via facebook who rebuilds the bosch VE pumps. It had the sticky vanes and other typcial issues of long term storage. I was glad to pay him to sort it as i didnt want to ruin my only good bosch pump.

Its on the car now, through the MOT and driving.

Although ive a couple of issues:

The auxillary belt seems to be wondering a bit, ive done the tensioner and the idler, now wondering if the alternator has a special pulley or something else in that line.

The other issue is that the car doesn't seem to be boosting a lot, i took boost pressure off the main boost hose leaving the intercooler before it enters the manifold there was a port for a sensor, that sensor was removed and ive fitted a fitting to take a pipe to the UFO on top of the pump.
Although the car still feels a bit like an SDI polo, relaxed and unhurried i suppose im using the displacement it has rather than a turbo but id like some boost. Im not overly sure how to tune an XUD but willing to learn.
One thing to note is the pump i have put on the car has a 9mm head, although i was told this is enough for a 2.1 unless i start looking for silly levels of black smoke felt spec power

The stop solenoid is at the bottom of the pump but what is the other solenoid on a fully mechanical bosch pump for? The higher up one? I have both wired to the same power source.

Also is the EGR required if its using the bosch pump, i just wonder what the lucas injection system was controlling that the bosch setup is not doing now.

[CitroJim]

The stop solenoid is at the bottom of the pump but what is the other solenoid on a fully mechanical bosch pump for? The higher up one? I have both wired to the same power source.

The top solenoid, on the round HP distributor at the end of the pump, is the stop solenoid.

The one on the face of the pump, lower down, is the cold advance solenoid. Only needs to be activated when the engine is stone-cold. Leaving it active all the time will cause the timing to be a little over-advanced; connect it to the glowplugs.

No EGR system can be controlled with this pump setup. Blank it off.

[PC2CV]

Thanks for that!

Meant to ask Jim would you have any interest in the EPIC pump and associated bits?
Its been in the shed since last year but before it goes to the scrap pile i thought id offer it to someone who appreciates them. Not looking anything for it if postage is covered its free.

[CitroJim]

And well done on doing a great bit of work

Meant to ask Jim would you have any interest in the EPIC pump and associated bits?
Its been in the shed since last year but before it goes to the scrap pile i thought id offer it to someone who appreciates them. Not looking anything for it if postage is covered its free.

Thanks for the offer but my days of playing with diesel pumps are now well in the past... Offer it in the For Sale/Wanted area; someone may very well be keen to have it.

Sorry I can't help much on your auxiliary belt. Last time I saw this problem was on a Citroen Xantia with the 2.1TD and the wrong hydraulic pump had been fitted. So often it's the tensioner suffering a broken axle but as you've checked it... The only other possibility is a worn clutch bearing on the A/C pump or the crank pulley dual-mass rubber is beginning to break up.

[PC2CV]

No worries jim, just recall you were quite positive about the EPIC, always appreciate someone who can persevere with something like that. But i will try on there thanks, would rather see it go to good use somewhere.

Had a go at blanking off the EGR, it seems a bit fiddly to actually remove the valve itself down the back of the engine, a job for another day. However, i cut a piece of thin steel and sandwiched it in just where the pipe enters the inlet manifold and blanked off the vacuum going to it. Feels a bit better now but need to get a boost gauge before any more adjustments are made.

I think the alternator belt clutch pulley might be the issue, at least thats what a few on the XUD tuning page on facebook reckon. I think from memory the crank pulley on this one was solid or was in good enough shape. Ive had them come apart on plenty of 2.0 and 2.2 HDi's now just getting to understand the quirks of the 2.1.

And of course the AC pulley also, ive a new cambelt kit coming so probably get a good look at all again all then. Hopefully its not the AC pump as its one surprising thing about this car it still has ice cold AC.