FIXED: Lucas Epic R86 40A 030A diesel fuel leak

T

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This is my first posting on this forum. I hope others will find it useful.

I have had a fuel leak on this pump for over a year now and not found any forum posts with a solution, just a long list of complainants suggesting that there's little point working on it, since it's a rubbish pump well known for leaking.

I have had no end of trouble finding the correct gaskets. Most places wanted to sell a complete kit of seals for £40 - whereas I only needed the seals from the base of the solenoids/actuators, total cost £5.50.

If your pump is leaking from the body seals then you will need to have it professionally refurbished by TT Automotive in Loughborough, tel: 01509 633 558 - as far as I can tell these are the only people in the country that handle these pumps. The other big Lucas workshop that I have found, PF Jones in Manchester, do not work on this pump.

You will need to set a whole day aside for this job if you are doing the actuators as well as the gaskets – the actuators can leak too, since they also have o ring gaskets that compress and harden.

Required tools:

Star sockets, many sizes, some very small.
Hammer.
Tool for removing jubilee clips.
usual spanners and sockets.
A work lamp.
You may also require a soldering iron and LEAD solder, not the nasty modern lead free stuff if poss.

Optional tools:

set of locking tools to assist with removal and refitting of the pump.
Multi meter

Required parts:

9007-497AL (6) - the o rings for the base of the solenoids.
9007-497bx (5) - the o rings for the piston of the solenoids.
total cost £5.50

Optional parts:

9160-101b (1) - the side actuator and stop solenoid group.
total cost £131.11
unknown - the top actuators
(I did not need these but probably about the same price)
Inlet manifold o rings.
set of glow plugs
silicone sealant (black if poss)
Heat shrink wrap.

Ensure your car's battery is in good condition and fully charged, since you will use a lot of power when priming the diesel system with the starter motor.

Introduction:

The Lucas fuel pump has three actuators and one stop solenoid. It works by opening and closing actuators to send the fuel round various parts of the pump and then relieving pressure as necessary.

At the top of the pump are the two relief actuators.
At the side of the pump, facing the back of the engine bay and below the wiring loom are the stop solenoid and the priming actuator. This pair are the hardest to get to and work upon.

The o rings at the base of the solenoids/actuators compress and harden over time, leaking fuel.

Also, the solenoids/actuators themselves have various o rings that compress and harden - you can get fuel leaking past these. It is possible to have these refurbished by TT Automotive but the original seals are no longer available, they cannot guarantee the work. Given the difficulty of replacing these parts I would suggest that you just bite the pillow and cough up, rather than having to do the soldering twice. Equally, if you have the cash, I suggest you replace both actuator pairs at the same time since this is quite hard work and you really don't want to be doing it twice.

Method:

Disconnect the battery, since you may be working on the electrical systems.

Remove the plastic engine floor coverings - you will find it much easier to recover items from your workshop floor than from the engine bay floor, particularly since many of the parts are black, the same colour as these plastics.

Remove the plastic lid from the top of the engine. I threw mine away, it gets in the way and no-one looks at your engine with the bonnet closed.

Remove the top intake hose that goes over the engine. Clean up all the soot whilst you're in there and clear any soot from the Exhaust Gas Recycler whilst you're at it.

Remove the intake manifold. Clean up all the soot whilst you're in there. If this is the first time this unit has been off then it is probably worth replacing all of the o rings that mate with the engine, as these will have also hardened.

Clean the soot and sludge from the intake barrels. Let your engine breathe.

Disconnect the wires to the glow plugs. Unbolt the frame and rotate it away from the engine.

This might be a good time to replace your glow plugs if you have not already done so, since you are putting the time in to strip the engine anyway.

Remove the fuel lines that go to the injectors, so that you can remove the fuel pump casing.

If you have the locking tools and you are going to replace the actuators, now would be a good time to remove the fuel pump. It's not strictly necessary, I managed to do the work without doing so, it was just much harder.

Disconnect the wiring loom from the car. If you trace the wires back you will see that it goes into the body and connects under the big triangular lid by the off side door hinges. The retainting clip hinges upwards, you can then just pull the connector out. You will need to remove the cable entirely, so that you can manipulate the cabling, it will make the job much easier.

Remove the cover from the fuel pump. It is a black plastic casing, there are two screws on the top that hold the top section on, and two more on the side facing the back of the engine bay. It is quite difficult to remove, it catches on various parts of the engine, you will need to give it a wiggle.

You should now have access to the actuators. There are four star bolts holding them down, diagonally offset. The one closest to the engine is hardest to remove, since other parts are in the way but it can be done, just be careful.

Remove the top actuator pair.

Remove the side actuator pair. It has an identical bolt grouping, you just cannot see it.

The side actuator pair cannot be drawn away from the pump, since the sensors on the pump are attached to the loom, as are the actuators. But the actuators can be moved aside.

You now have access to the wells in which the actuators rest. Hook out the old gaskets and replace. You only need three of the small ones and four of the large ones, but they do not always stay put and so I suggested you order too many for this reason.

You might find that the gaskets stay in better if you wet them with a small amount of diesel.

If you are not replacing the actuators you can now reassemble your engine and test - I would not put the pump casings back on yet personally, until you are sure that the gaskets are doing their job and you do not need to replace the actuators. The engine can be run without the intake manifold, it's just noisy. Let it warm up fully and check for leaks. In my case the side actuator pair was still leaking, so I had to do the whole job.

If you are replacing the actuators then you will need to unbolt the loom from the pump. You will need very small star sockets for this job, such as you might find in a set of security screw tools. Allen keys will not fit well and slip, stripping the heads, though you might find a flat-blade screwdriver that will fit if you're lucky.

Once you have all the casings for the wiring loom apart you will see that the wires are sealed with silicone sealant. This will all have to come out. At this point you may find that the insulation on the wires have all cracked. You will need to cut the loom back to refurbish this, otherwise the wires will short. If not, skip the next few sections that deal with stripping back the loom and repairing this problem.

Cut the wires back an inch from the circuit board, leaving the tails still soldered on to the board. This is so that you can clearly see which coloured wires go where when re-soldering. You should also make a diagram of both sides of the circuit board at this point, in case something goes wrong, with all colours marked. You will also need to cut off or de-solder the actuators. DO NOT CUT the actuator pair that you are not replacing, just the actuator pair that you are replacing. You will need to use the soldering iron to de-solder the actuators that you are keeping, so that you can remove the circuit board and wiring loom from the car.

Once you have the wiring loom removed, place it on the ground and smash off the plastic collar with a hammer. Not, obviously, the end that connects back to the car, just the end that mounts onto the fuel pump. This part is moulded on at the factory, You cannot pull the wiring through. It has to be smashed off.

Cut the sleeving back an inch, cut off the insulation at the ends of your wires leaving 5mm bare wire then twist them and tin the ends ready for re-soldering back to the circuit board. Wrap the sleeving in electrical tape, sufficient diameter to closely replicate the diameter of the original plastic part. You will find the thick black wire that went into the wiring loom is actually a common ground that is not insulated, having instead a heat shrink wrap. You will need to replace this wrapping.

It is easier to do the soldering work if you loosely mount the actuators in their rightful place, complete with plastic mount. The side actuators are held on with the blackened machine screws, these are longer than the gold screws for the top actuators since they also hold the plastic mount on. You only want to use a couple of screws and only loosely – you're just looking to take the weight off.

When doing the soldering work, take a look at your diagram and ensure you have a rough idea where everything goes, particularly which way round the actuators are soldered in.

Hopefully you will have followed my advice and left an inch of wire still attached to the circuit board.

DO NOT remove all of the wires at once. De-solder one by one and place the wire on top of the engine so that you can clearly see which wire you're supposed to be doing. whilst the solder is still hot you can introduce the new wire into the hole from the rear of the circuit board. This is quite fiddly, the more light you have the better. Once you have done that wire you should throw away your guide wire from the top of the engine bay and do the next one. Take care with the routing of the wires for the actuators, you don't want to have to repeat that work.

Check your work against your diagram, also it could not hurt to test with a multimeter that you don't have any shorted or crossed circuits – you don't want to blow your ECU of pump controller.

Once you have done all of the solder work you can re-assemble the circuit board in its mount. I forgot to screw the board down but it doesn't matter because the silicone holds it all together and there is a top lid in any case.

Clean all of the old silicone off from the plastic parts and replace the wires in their guide slots, holding them in their correct positions. The lid will not fit back on unless you get these correct. There are slots for both the top and bottom rows of wire. Splooge lots more silicone in the appropriate places, to seal the wires and hold them in place. You're looking for a watertight, airtight seal that also stops the wires from moving about. You may have noticed how bright and shiny the solder work was before you started, not bad for a 14-year old car. You're looking to replicate that level of seal.

Once the circuit board is back together you will need to replicate the plastic collar that you hammered off earlier. I wound some electrical tape around the sleeving and made a clamp from a plastic take away food lid – much like the clamp you would find in a mains plug. A metal brace would probably hold the wire better. Point being, you don't want the cable flapping about in the engine bay and tearing all of your signal cables.

Now you need to properly re-assemble your actuators, ensuring that all of the gaskets are in the right places. Replace your injector pipes and glow plug leads and, without replacing the inlet manifold, fire up the engine to test. You will find that it will require several turns to start since there is no fuel in the system and it will need to prime. Some Easy Start might help to get things going again, just floor the throttle to keep the engine going until all the air is purged.

Assuming all is well you can now re-assemble your engine.
 

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