New fuel pump

If your Delta won't go at all, the fuel pump relay may have failed. If the car is a bit down on power, misses a bit now and then, and is slow to start, it's more likely the fuel pump is about to fail.

If you listen to the symptoms, you can change the pump before it stops altogether, saving a roadside rescue and doing the job at your leisure. A new fuel pump is £89 at Tanc's, so it's not that expensive, and it's a job you can do yourself. Here's how...

The pump is located under the back seat. So fold the seats forward and remove the plastic dust sheet, then remove both side rear plastic door shields so you can roll the underseat carpet forward to clear your work area

Undo the 8mm nuts securing the metal pump cover, give the area a quick clean so crap doesn't go in the tank.

 

Remove the tank top pipe clamp and pull out the 2 fuel pipes, then remove the soft rubber gasket.

Undo the 8mm nuts securing the car body pipe clamps, including the 2nd clamp at the far end, and move the pipes clear.

Before you disconnect the battery, remove the 2 pin plug to the pump, there's a small clip at the bottom, and just check the voltage reading. Low voltage to the pump has the same effect as a failing pump.

 

Then disconnect the battery, you do not want a spark!

The pump and its top mounting are secured by a plastic ring, this has raised ribs on it. Use a worn flat screwdriver and tap the ring anti clockwise, it will then loosen.

Undo and remove it, the pump mounting top is a snug fit in the top tank hole, pull it upwards.

 

Attached to the pump, you'll find there's a copper pipe coil and rubber pipes, you'll have to remove this before you can pull the pump through its hole. Undo the rubber pipe at the pump top, and the outlet pipe at the mounting. Let it go and pull the pump out of its hole, you can get it out of the tank next.

It's a tight fit, and will take a bit of wiggling, but it'll come out, then collect the balancer coil.

Put the metal cover over the tank hole, then take the whole unit to the bench.

Hammer off the plastic ring.

Pull out the pump.

The pump from Tanc is a Walbro pump, this replaces the original. It's a smaller pump so it needs a wider rubber mounting, this is supplied with the kit. I think the pump has a bit higher output than the old Bosch unit. Let's hope so!

On the bench, unclip the mounting blades and remove the plastic top, pull the old pump out of its swirl pot, undo the screws and remove the filter, give this a good clean.

Give inside the swirl pot a good clean too.

 

There's a plastic cap protecting the new pump intake, be sure to remove this!

Squeeze the pump into it's red mounting, refit then squeeze this into the plastic casing.

The Walbro pump has spade fittings, you'll have to change the original bolt on fittings for spade clips, one is of course smaller than the other,

Refit the filter and push the unit back into the swirl pot, don't forget the short vent pipe.

Clip the mounting blades onto the swirl pot

and go to the car. Put the coil and pipes into the tank first,keep hold of an end, then drop the pump unit in, you'll have to refit the coil's rubber pipes now, with the unit in place.

 

Push the pump top down into its seal, then refit the top securing ring, the pipes should line up before tightening this, fit the rubber seal, then the pipe central securing clip.

Replace the pipe mounts and nuts, then connect the battery and refit the electric plug. Start the car to test the pump before you fix everything back on, it will start!

 

Then replace the metal cover, plastic doorsteps and put the seat down, a roadtest will be fun!

 

Call me old fashioned, but the thought of electrical connections, especially if I've connected them, in a big tank of explosive liquid

makes me very nervous! But it seems to work, and our Delta does run better, this is an important component and most are reaching the end of their service life after 20 years. With care, this is a DIY job.