Fitting an Electric Fuel Pump to a VW Bay Window: Facet Pump & Malpassi Regulator

Jenny's freshly rebuilt 1600cc engine — the electric fuel pump and Malpassi regulator were among the last jobs on the rebuild.

Why I Made the Switch

Let me be upfront: this upgrade isn't for the purists. If you're all about keeping your Bay Window 100% original, this one's not for you — and that's completely fine. But if, like me, you use your van for actual family camping trips and the thought of leaving your kids stranded on the hard shoulder fills you with dread, then read on.

My mechanical fuel pump was on its way out. The VW 1600's original mechanical pump is driven by a pushrod off the camshaft — a clever bit of 1960s engineering that works perfectly well when everything is in good shape. But mine wasn't in good shape. It was getting weak, inconsistent, and I could feel it in the way Jenny ran. Given that I was already deep into a full engine rebuild, it seemed like exactly the right moment to make the switch to electric.

The other thing worth mentioning: modern petrol — particularly the E10 fuel now standard at UK pumps — is hard on the rubber diaphragms inside old mechanical pumps. Ethanol attacks the seals, and replacement pumps vary wildly in quality. An electric pump removes all of that uncertainty.

My reference library for this job — the Haynes manuals and How to Restore Volkswagen Bus are all well worth having.

As always with jobs on Jenny, I had my books close by. The Haynes VW Bay Transporter Restoration Manual and the legendary How to Keep Your Volkswagen Alive by John Muir are both invaluable for understanding how the fuel system fits together before you start pulling things apart.

John Muir's manual — written for the "compleat idiot," which is exactly what I am when it comes to some of this stuff.

What You'll Need

Here's the full shopping list for this job. I've linked everything I used — these are affiliate links which help keep this site running at no extra cost to you.

Why a Facet Pump?

The Facet pump fresh out of the box — compact, simple, and widely used in the VW community.

The Facet is a popular choice in the VW Bay community for a few good reasons. It's a low-pressure solenoid-operated pump that's well suited to carburetted engines, it's compact enough to tuck away neatly, and there's a huge amount of real-world experience with them on Bays and Beetles online if you run into any issues.

One thing to be aware of: the Facet is better at pushing fuel than pulling it. This means the best mounting position is as close to the fuel tank as possible — ideally below it or at the same level — so it's pushing fuel to the engine rather than trying to suck it from a distance. On a Bay Window, mounting it near the rear on the nearside chassis rail or inner arch works well, keeping the pump close to the tank outlet.

Mount it on rubber bobbins rather than bolting it directly to bare metal. The Facet produces an audible ticking when it's running — it's perfectly normal, but rigid mounting transfers that vibration into the body and makes it much more noticeable in the cab.

Wiring It Up

The wiring is straightforward but needs to be done properly — you don't want an unswitched fuel pump running continuously. The pump should be wired so it only runs when the ignition is on. The two standard approaches are:

Simple wiring: Run a fused feed (6 amp fuse) from a switched ignition live — the coil positive terminal works well — to the pump positive wire. Earth the pump to the chassis with a clean, paint-free connection. This is what I did and it works reliably.

Via a relay: The more complete solution is to wire the pump through a relay, which protects your ignition switch from the pump's current draw. It also makes it easy to add a priming switch on the dash, which lets you pressurise the fuel system before cranking — handy for cold starts after the van has been sitting for a while.

Whichever approach you use: always fuse the live feed. VW never fused the ignition circuit on these vans, so you need to add your own protection. A 6 amp inline fuse is standard for the Facet.

Getting familiar with the engine bay — this is not a glamorous job but it's very achievable if you take your time.

Removing the Mechanical Pump & Fitting the Blanking Plate

The blanking plate — this seals the mechanical pump aperture in the engine case once you remove the original pump.

Once you've removed the mechanical pump — two bolts, a bit of wiggling, and watch for fuel spillage — you'll be left with an open hole in the engine case where the pump pushrod sits. This needs to be sealed with a blanking plate. Don't skip this step and don't leave it open even temporarily. The pushrod will drop into the engine if you're not careful, and the hole allows unfiltered air into the crankcase.

The blanking plate bolts straight in where the old pump lived, with a new gasket. It's a five-minute job but an important one. Clean up any old gasket material from the mating surface before fitting the new one.

Why You Need the Malpassi Fuel Pressure Regulator

The Malpassi Filter King regulator fitted and plumbed in — it also acts as an additional fuel filter, which is a bonus.

This is where a lot of people come unstuck. The Facet pump puts out more pressure than a Weber carburettor is happy with. The Weber 32/36 wants to see somewhere between 2.5 and 3.5 PSI — push more than that through it and you'll be forcing fuel past the needle valve in the float bowl, flooding the carb, running rich, and potentially causing all sorts of running issues.

The Malpassi Filter King regulator sits in the fuel line between the pump and the carb and drops the pressure down to the correct level. It's adjustable, it doubles up as a filter, and it's a well-proven bit of kit in the VW world. Mount it as close to the carb as possible — on the firewall near the engine — to get the most accurate pressure at the carburettor inlet.

The inline pressure gauge temporarily fitted to dial in the Malpassi regulator. Remove it once you've set the pressure and replace with the blanking plug.

The Installation: Step by Step

Here's how I approached the full job. Take your time, work safely, and make sure the engine is cold before you start touching anything fuel-related.

1. Disconnect the battery. Always. Non-negotiable when working on fuel systems.
2. Remove the mechanical fuel pump. Two bolts, disconnect the fuel lines (have a rag ready), and carefully withdraw the pump and pushrod together. Keep the pushrod — you'll need to make sure it doesn't fall into the engine.
3. Fit the blanking plate. Clean the mating surface, fit a new gasket, and torque the bolts down evenly. Don't overtighten.
4. Mount the Facet pump. Near the rear of the van, close to the fuel tank outlet. Mount on rubber bobbins. Make sure the arrow on the pump body is pointing in the direction of fuel flow (towards the engine).
5. Run new fuel hose from the tank outlet to the pump inlet, and from the pump outlet towards the engine. Use proper ethanol-resistant fuel hose and secure every joint with jubilee clips — two clips per joint for fuel-carrying connections is good practice.
6. Mount the Malpassi regulator on the firewall in the engine bay, between the pump outlet and the carburettor inlet. This is also where you'll temporarily fit the inline pressure gauge for setting up.
7. Wire up the pump. Fused live feed from a switched ignition source, earth to clean bare chassis metal.
8. Reconnect the battery, turn the ignition on (don't crank yet), and check every fuel connection for leaks. The pump will pressurise the system the moment the ignition is on.
9. Start the engine and set the regulator. With the inline gauge fitted, adjust the Malpassi until you read 2.5–3 PSI. On my Weber 32/36, I found 2.5 PSI worked well.
10. Shut the engine off, remove the inline gauge, and fit the blanking plug. Check all connections one final time, then start the engine again and check for leaks.

How It's Running

I've been running the electric pump for a few months now and I'm genuinely pleased with it. Jenny's been running better than ever — smoother throttle response, consistent fuelling, and that background anxiety of "is the pump going to give up on the M6?" has pretty much gone.

I can't claim the electric pump alone is responsible for all of that — it was one of the last jobs on a full engine rebuild that included a new clutch, oil cooler, fresh seals throughout, a Weber carb, and Bilstein shocks. But consistent fuel delivery matters, and knowing the pump isn't going to fail mid-motorway is worth every penny of what this cost.

For context, I took this on as part of a wider engine rebuild and it was well within the capabilities of a home mechanic with a decent set of tools and a willingness to read up first. If you're comfortable with basic plumbing and electrics, it's a very achievable job.

Common Questions

Do I need a fuel pressure regulator with a Facet pump?

If you're running a Weber carb, yes — absolutely. The Weber 32/36 is sensitive to pressure above 3.5 PSI. Too much pressure forces the needle off its seat in the float bowl and you'll flood the carb. The Malpassi Filter King is the go-to regulator for this job in the VW community.

Where should I mount the Facet pump?

As close to the fuel tank as possible, and ideally below it. The Facet pushes fuel better than it pulls it, so you want gravity helping it rather than hindering it. On a Bay Window, the nearside rear arch area near the tank outlet is a common mounting point.

Will it affect the van's originality or value?

Technically yes — it's not an original part. But the blanking plate installation is reversible. If you ever wanted to go back to a mechanical pump, it's straightforward to do. For a van you actually use and drive, reliability tends to trump originality for most owners.

Is this hard to do?

It's not a beginner's first job, but it's well within reach of a home mechanic who's comfortable with basic plumbing and electrics. The most important things are: read up first, work safely, and don't rush the pressure-setting stage.

Why does my Facet pump tick?

It's normal. The Facet is a solenoid pump and makes an audible ticking when running. If it's mounted directly to sheet metal it can sound surprisingly loud. Rubber bobbins help significantly.