Lucas EPIC Injection Pump Overhaul Guide

This is the Forum for all your Citroen Technical Questions, Problems or Advice.

Moderator: RichardW

Post Reply
Online
User avatar
moizeau
(Donor 2022)
Posts: 1580
Joined: 12 Jan 2015, 16:08
Location: France 36
My Cars: 91 BX TZD Estate. Dead but loved
407 HDI 136 auto
C4 2l petrol coupé
2010 Dispatch III HDI 90
AND a 1980 Z1000ST
AND a 1983 GPz1100 inj
AND a 1995 Zephyr 1100
AND a 1980 Z650 (my moped)
x 315

Re: Lucas EPIC Injection Pump Overhaul Guide

Post by moizeau »

There are no sizes listed in the documentation unfortunately and mine are in the pump. You can measure the old one or the seat then order from that. O rings are sized by their internal diameter and the thickness, e.g. 10.0mm (ID) x 1.5mm (diameter of the rubber section). Obviously, only use o rings suitable for fuels, not gardening equipment.
Pete
Notice the BX is still top the list but sadly gone
velvetpig
Posts: 2
Joined: 13 May 2019, 14:32
Location: Australia
My Cars: transitvan

Re: Lucas EPIC Injection Pump Overhaul Guide

Post by velvetpig »

moizeau wrote: 13 May 2019, 22:28 There are no sizes listed in the documentation unfortunately and mine are in the pump. You can measure the old one or the seat then order from that. O rings are sized by their internal diameter and the thickness, e.g. 10.0mm (ID) x 1.5mm (diameter of the rubber section). Obviously, only use o rings suitable for fuels, not gardening equipment.


Thanks for your reply moizeau,
The pics are not of my pump, got them from the net.
The "O" Ring in my pump is 1.7mm (diameter of the rubber section)
The "O" Ring in the pic looks to be around 2.5mm i will look around for something similar.
Cheers
Vinyl
Posts: 15
Joined: 03 Feb 2021, 06:26
Location: Nantes
My Cars: Citroen xm

Re: Lucas EPIC Injection Pump Overhaul Guide

Post by Vinyl »

Hello I am New to the forum and I Came Here particularly for this thread.

And I have to say hats off for all of the contributors to this thread

internet is Full Of not so Professional opiniones about this Pump So I am very happy to see some actual solutions to be implemented

@moizeau question to you as a leading expert to this thread: can the top solenoids be accessed conveniently through any possible maintenance doors/ claps or should the pump need to be decomposed fully using hydraulic pump as seen on the photos from the beginning of the thread?

Also can anyone tell me what might be the actual link between wear of those solenoids orings and the official service note for the pump as issued by some manufacturers (namely Renault if I remember correctly), with the latter advising to put a narrow washer between the pump body and rotor position sensor.

Lastly, in that thread it was mentioned that there is some elaborate instruction on this pump if anyone has it please PM me, thanks
Online
User avatar
moizeau
(Donor 2022)
Posts: 1580
Joined: 12 Jan 2015, 16:08
Location: France 36
My Cars: 91 BX TZD Estate. Dead but loved
407 HDI 136 auto
C4 2l petrol coupé
2010 Dispatch III HDI 90
AND a 1980 Z1000ST
AND a 1983 GPz1100 inj
AND a 1995 Zephyr 1100
AND a 1980 Z650 (my moped)
x 315

Re: Lucas EPIC Injection Pump Overhaul Guide

Post by moizeau »

Vinyl, firstly welcome. Secondly, Jim is the expert, without him I wouldn't have known where to start. I just happened to be pulling mine apart more recently, but thanks for the compliment.
What issues are you having?
Be very careful when going anywhere near the wiring hidden underneath the cover. The insulation falls off after time just by looking at it and then you're into a rewire.
Why do want to get inside the top solenoids? It can be done in situ but don't if you're not certain there is a problem due to the wires.
Pete
Notice the BX is still top the list but sadly gone
Vinyl
Posts: 15
Joined: 03 Feb 2021, 06:26
Location: Nantes
My Cars: Citroen xm

Re: Lucas EPIC Injection Pump Overhaul Guide

Post by Vinyl »

@moizeau thanks for a fast reply

The engine runs lumpy on the cold days especially bad on foggy cold days

In the weather below zero Celsius it fires, runs couple minutes and shuts off when warm with rotor position indicated in the ECU error s

Ironically enough - in worm weather it runs perfectly, accelerates pretty fine

I think those orings accompanying solenoids are to be blamed as someone indicated here in the thread (not remember maybe it was you)

It s just a big handicap - having a car that during summer runs perfectly (with occasional problems on foggy cold summer mornings) and not being able to us e it during winter when is needed the most.

Do you think that procedures you explained in your post from 14 Feb 2017 (this thread) could be the fix to issues of mine?
Thanks, vinyl
Online
User avatar
moizeau
(Donor 2022)
Posts: 1580
Joined: 12 Jan 2015, 16:08
Location: France 36
My Cars: 91 BX TZD Estate. Dead but loved
407 HDI 136 auto
C4 2l petrol coupé
2010 Dispatch III HDI 90
AND a 1980 Z1000ST
AND a 1983 GPz1100 inj
AND a 1995 Zephyr 1100
AND a 1980 Z650 (my moped)
x 315

Re: Lucas EPIC Injection Pump Overhaul Guide

Post by moizeau »

I'd check all the normal reasons (non Epic) for a diesel engine to run rough first. Mine got worse as it warmed up. Check for air getting in, use a clear fuel line going into the pump and look for bubbles. Also the fuel filter and it's o ring and not forgetting all 4 glow plugs are working.
You say that there is a 'rotor position' error? What diagnostic kit are you using? The first time I rebuilt the pump I put the rotor in 180 degrees out and it wouldn't start, nothing was shown up in PP2000, there is no sensor in the pump to know where it is as far as I'm aware. I take it the car in question is your XM?
Go through the basic stuff first then if it's still the same we can go onto the solenoid o rings. I can't stress enough how fragile the insulation is on the exposed wires under the cover.
Good luck and let us know how you get on.
Pete
Notice the BX is still top the list but sadly gone
Vinyl
Posts: 15
Joined: 03 Feb 2021, 06:26
Location: Nantes
My Cars: Citroen xm

Re: Lucas EPIC Injection Pump Overhaul Guide

Post by Vinyl »

Ok I am after my first ever hands-on experience with fuel system.

I run motor for couple minutes just to warm it a little to make those plastic fuel terminals easier to disconnect

Upon successfully taking them off I was surprised to find them completely empty (no fuel dropping from them at all).

I know that after shuting the engine off certain under-pressure occurs at these terminals - yet I expected them both to be full of diesel. Taking them off the engine took me some time as it was the first time I did this, yet still engine couple minutes earlier was running normally.

Should I be concerned about it?
Attachments
20210204_094040.jpg
Vinyl
Posts: 15
Joined: 03 Feb 2021, 06:26
Location: Nantes
My Cars: Citroen xm

Re: Lucas EPIC Injection Pump Overhaul Guide

Post by Vinyl »

Also @moizeau:

I don't have any Pro equipment to this pomp only basic standard obd connector

If I remember correctly it was not rotor but rather it was actuator position error

And it's not Xm (but hell do I respect those, mainly for they marvelous alcantara upholstery they don't do these like that anymore) it is on my Punto ii
Online
User avatar
moizeau
(Donor 2022)
Posts: 1580
Joined: 12 Jan 2015, 16:08
Location: France 36
My Cars: 91 BX TZD Estate. Dead but loved
407 HDI 136 auto
C4 2l petrol coupé
2010 Dispatch III HDI 90
AND a 1980 Z1000ST
AND a 1983 GPz1100 inj
AND a 1995 Zephyr 1100
AND a 1980 Z650 (my moped)
x 315

Re: Lucas EPIC Injection Pump Overhaul Guide

Post by moizeau »

Ah, the Fiat version. I've never seen one. The Epic workshop manual I have is for PSA / Mercedes, so these are very similar to the point that the o ring repair kit also serves both. The fact that Fiat and Renault aren't mentioned would suggest they are a different beast. With this in mind I wouldn't take any measurements listed in this thread as true for your pump. The 'clip on' fuel hoses are different on PSA as well, they are 'banjos'. The Epic pump in this thread refers to the indirect diesel engine, not the common rail.
I would expect to see fuel there but having not ever done this on a Fiat I'm not sure.
Maybe someone who knows this engine / setup better may be able to advise.

Ages ago I helped a friend on a petrol Fiat and found a very useful Fiat forum in the UK.
Pete
Notice the BX is still top the list but sadly gone
User avatar
CitroJim
A very naughty boy
Posts: 49532
Joined: 30 Apr 2005, 23:33
Location: Paggers
My Cars: Bluebell the AX, Polly the C3 Picasso, Pix the Nissan Pixo, Propel the duathlon bike, TCR Pro the road bike and Fuji the TT bike...
x 6163
Contact:

Re: Lucas EPIC Injection Pump Overhaul Guide

Post by CitroJim »

moizeau wrote: 04 Feb 2021, 16:20 I would expect to see fuel there but having not ever done this on a Fiat I'm not sure.
Although I have no Fiat experience I'd have expected to see plenty of fuel here...

Maybe that's the root of the problem. The EPIC relies upon a good supply of clean fuel from the tank via the filter and if it does not then it can do all sorts of odd things...

Before proceeding any further I'd be checking the filter, the strainer in the tank and all points between tank and pump for air ingress...
Jim

Runner, cyclist, time triallist, duathlete, Citroen AX fan and the CCC Citroenian 'From A to Z' Columnist...
Vinyl
Posts: 15
Joined: 03 Feb 2021, 06:26
Location: Nantes
My Cars: Citroen xm

Re: Lucas EPIC Injection Pump Overhaul Guide

Post by Vinyl »

@moizeau

First foremost thanks for the info about Italian forum, any help appreciated :)

Here are couple dodges I have to make to what you wrote, and not being smartass, correct me please if I am wrong:

My pump is not common rail - it is normal rotation sequential pump ( although you're right- this generation of Punto was the first to present common rail - btw it's the same exact engine as mine only with modified engine head) the engine legitimates itself with 60 hp

True is the dimensions (of the pump) can differ, as the output and volumes of different engines across different manufacturers also differ

Another thing that might pose as trivia for you is that where I come from PL this pump has so bad reputation that the most common and most gratified solution across environment of specialists and mechanics is to get rid of it and- wait for it- install in its place bosch pump instead leaving the old engine. I know that for people from Western Europe it is just incomprehensible how could it be done, but there are people, literally now I can go to ad portal like your gumtree and find guys offering such switchover

Is this surprise to you? :) I know stories of Germans whose jaws fall to the ground when they saw polish guy riding Berlingo with customly installed Bosch pomp, yet with full honesty I tell you this is legitimate solution where I live

@CitroJim many thanks for your reply, I also thought this might be the problem, and again - much admiration for your expertise in this topic
User avatar
CitroJim
A very naughty boy
Posts: 49532
Joined: 30 Apr 2005, 23:33
Location: Paggers
My Cars: Bluebell the AX, Polly the C3 Picasso, Pix the Nissan Pixo, Propel the duathlon bike, TCR Pro the road bike and Fuji the TT bike...
x 6163
Contact:

Re: Lucas EPIC Injection Pump Overhaul Guide

Post by CitroJim »

Vinyl wrote: 04 Feb 2021, 17:35 Another thing that might pose as trivia for you is that where I come from PL this pump has so bad reputation that the most common and most gratified solution across environment of specialists and mechanics is to get rid of it and- wait for it- install in its place bosch pump instead leaving the old engine.
They have a bad reputation here in the UK too! Swapping it for a Bosch VP20 can certainly be done, certainly on the PSA 2.1TD diesel engine that used the EPIC pump... Early versions of this engine indeed used a fully mechanical Lucas DPC pump...

If all else fails, it might be a solution... But as a last resort...
Jim

Runner, cyclist, time triallist, duathlete, Citroen AX fan and the CCC Citroenian 'From A to Z' Columnist...
Online
User avatar
moizeau
(Donor 2022)
Posts: 1580
Joined: 12 Jan 2015, 16:08
Location: France 36
My Cars: 91 BX TZD Estate. Dead but loved
407 HDI 136 auto
C4 2l petrol coupé
2010 Dispatch III HDI 90
AND a 1980 Z1000ST
AND a 1983 GPz1100 inj
AND a 1995 Zephyr 1100
AND a 1980 Z650 (my moped)
x 315

Re: Lucas EPIC Injection Pump Overhaul Guide

Post by moizeau »

Yep, a lot of conversions have been done, either to replace the Epic because of issues or to run veg. It's also been done on the 1.7 and 1.9 PSA, replacing the Lucas pump for a Bosch...for veg.
This aside, I'd certainly look at 'standard' issues first and make sure fuel is getting to the pump correctly.
The Fiat site was based in the UK I think.
Pete
Notice the BX is still top the list but sadly gone
Vinyl
Posts: 15
Joined: 03 Feb 2021, 06:26
Location: Nantes
My Cars: Citroen xm

Re: Lucas EPIC Injection Pump Overhaul Guide

Post by Vinyl »

Meanwhile can someone please explain to me how these valves really work?
I know it's a complex mechanism but I have a problem with understanding basics: as I understand the operation of a valve unit is that it modifies pressure - therefore there should be a pipe that transmits the fluid into it (source) and the pipe that receives the output of the fluid as modified by the valve.
So there should be two wholes one delivering and one receiving the pressure.
Yet the pump has 4 valves with only 1 whole in each (see pages 24-26)
How does these valves work? Particularly one responsible for increasing the volume in the high section and one that decrease it.

I know that these are basics but it's extremely not intuitive and I didn't find it in any material (see page 28 of the link I pasted, there clearly are two fuel lines to each valve yet again- there's only one whole in each valve physically)

I hope I explained my doubts clearly.
User avatar
CitroJim
A very naughty boy
Posts: 49532
Joined: 30 Apr 2005, 23:33
Location: Paggers
My Cars: Bluebell the AX, Polly the C3 Picasso, Pix the Nissan Pixo, Propel the duathlon bike, TCR Pro the road bike and Fuji the TT bike...
x 6163
Contact:

Re: Lucas EPIC Injection Pump Overhaul Guide

Post by CitroJim »

They are just small electrovalves (solenoid operated valves) under ECU control to regulate injection timing and volume of fuel delivered to regulate speed. One of them is analogous to the stop solenoid in a conventional mechanical pump.
Jim

Runner, cyclist, time triallist, duathlete, Citroen AX fan and the CCC Citroenian 'From A to Z' Columnist...
Post Reply