Fitting new seals on Bosch pump

toddao · Post by **toddao** » Wed Mar 12, 2008 10:39 am

Bosch have managed to find me a seal set for my pump - three pieces. Question is : am I mad to even attempt changing them seeing as I only have a rudimentary diagram of the pump in the Haynes? I suspect one seal is for the shaft where it drives off the cam-belt, another for the accelator lever (?) and the third? Anyone have any ideas.
The source of my leak is the rear timing inspection cover but the man at Bosch says all three must be changed.
I'm a bit in the dark with this, so any advice greatly appreciated before I order this set then sit there with a load of parts..

Cheers

DavidRutherford · Post by **DavidRutherford** » Wed Mar 12, 2008 11:43 am

On the bosch pump there's also the stop lever and the idle speed lever to consider.

That should then be 4: Driveshaft, accelerator lever, idle speed lever and stop lever.

The driveshaft should be a standard lipped oil seal, but the other three are essentially just O-rings.

CitroXim · Post by **CitroXim** » Wed Mar 12, 2008 1:11 pm

Hi Todd,

David is spot on, the drive shaft one is a normal lip seal.

You have a big, shaped O ring under the pump top cover, an O ring behind the distributor and a few smaller ones on the throttle shaft and idle and emergency stop shafts.

They're not hard to replace but the pump has to come off the car to do the job properly and without risk. That is perhaps the most difficult job, especially getting the bottom retaining nut and washer off (well it is on a Xantia because the hydraulic pump gets in the way). Before removing, scribe a line across the pump mounting flange to the pump carrier so you can replace it later in exactly the same position.

The pump must be carefully cleaned of all crud and work must be carried out in clinically clean conditions.

The top lid comes off after removing the throttle lever and the four screws holding it down. Don't force it off as the throttle shaft/governor spring will prevent it and also a small spring between the idle control shaft and governor lever has to be carefully disconnected. Finally, carefully push the throttle shaft down through the boss whilst gently lifting the cover and the cover will then come off with a bit of jiggling to free the maximum fuelling adjustment screw plate.

Go gently, looking for obstacles all the time.

Then replace the seals and carefully reassemble.

If you've never played with a pump like this before, it is a good idea to practice on a scrap pump first.

I've never replaced the driveshaft seal nor the distributor seal but if you need a bit of further information on doing these two jobs, I have a scrap pump at home I can practice on and take some pictures. For ages I've been planning a photo-strip of a pump so perhaps I'd better get around to it.

When replacing the pump, make sure you do the mounting nuts up very tightly and make sure all washers go back on. The pump vibrates enough in use to shackle any nuts off in a short time that are not well done up.

toddao · Post by **toddao** » Wed Mar 12, 2008 1:43 pm

Thanks for replies fellas. With that description Jim, I feel better about doing it. Bosch are charging me €40 for these bits of rubber! It would be ironic if I changed these seals and it still leaks because, as I said the leak seems to be coming from the small plate to the rear of the pump secured with two bolts.
I collect the seals tomorrow then I'll attempt the operation. Good to know there's some advice to be had!

CitroXim · Post by **CitroXim** » Wed Mar 12, 2008 1:49 pm

toddao wrote: the leak seems to be coming from the small plate to the rear of the pump secured with two bolts.

Is that from the cover that is vaugely oval shaped? In which case, that is the timing device cover and all that is under there is another O ring. A doddle to replace but not without taking the pump off

Just be careful there is a big spring behind that cover

You won't even need a Bosch seal for this as long as you can find the right size of O ring that is 100% guaranteed to be diesel-proof.

I'd strongly advise not to disturb the top cover and throttle shaft etc if these are not leaking. best to let these sleeping dogs lie and just do the bit that is leaking.

cauchoiskev · Post by **cauchoiskev** » Wed Mar 12, 2008 9:49 pm

Slightly off topic

Does anybody know where to find the model number of these little beggars (Bosch pumps). There are minute numbers stamped all over them, but none seem to correspond to the Haynes references

.

CitroXim · Post by **CitroXim** » Thu Mar 13, 2008 7:44 am

cauchoiskev wrote:Slightly off topic

Does anybody know where to find the model number of these little beggars (Bosch pumps). There are minute numbers stamped all over them, but none seem to correspond to the Haynes references .

Look for the long Bosch part number (10 digits) stamped on the flat area of casting and then do a web lookup in Google. There are may variations of the same basic pump but if you need spares you'll need this part number. It's the same with a Lucas Pump, in which case the model number is on the blue plate underneath the pump.

Surely you don't expect the haynes BoL to tell you anything useful do you?

toddao · Post by **toddao** » Thu Mar 13, 2008 4:31 pm

Just came back from Bosch and it turns out that I had misunderstood what the man had told me on the phone. They had ordered a complete pump refurb kit which is three different boxes ( not three pieces of rubber!) : one containing numerous seals, gaskets, washers and plastic caps to screw onto the injectors to keep them clean. Another with a large squarish rubber seal (?) and the final one with a new accelerator lever - he'd noticed that mine was worn and had too much play in it.
In there somewhere is that O ring that I need ! Hopefully that will sort it, I won't have to open it, though it's all there if I have to refurb it now!

cauchoiskev · Post by **cauchoiskev** » Thu Mar 13, 2008 6:22 pm

citrojim wrote: Look for the long Bosch part number (10 digits) stamped on the flat area of casting

I take it you mean the front face, where "Bosch" is marked, Citrojim ? I didn't notice anything there ressembling a 10-digit code, I'll take another look tomorrow...