Lotus Elan and Lotus Elan Plus 2 Forums

I see much correspondence re. fitting an electric fuel pump. Is this instead of the mechanical pump or is it additional to give it a hand?
Jim

Instead of

Yep, instead of. Then you get a nice alloy blanking plate for where the mechanical fuel pump was.

Silly question, but what's the advantage of an electrical fuel pump?

None really. Quite risky to run without an inertial cutoff switch in case of a rollover or the driver is incapacitated. Worst thing that the mechanical pump can do is rupture the diaphram and fill the crankcase with fuel. Some engines (my old '53 Chevy 216) have been destroyed from a slight leak and it thins out the oil enough to wipe out the oil fed bearings. If the oil level ever goes up or reeks of gasoline that's a clue!

The new mechanical pump I installed but out 5.5 psi at idle. Decided to install a fuel pressure regulator to drop the pressure exerted on the Weber float valves to 2.5. Their technical literature requires it be from 1.5 to 3.5 psi.

However, if you're looking to lighten the car by every ounce then the jackshaft can be lopped off just past the middle bearing journal and the rear bearing shell rotated to block off the oil gallery. You're a real racer then.

Hey Steve, love the new picture!
-Keith

Jim,

I much prefer an electric fuel pump. I've had one fitted to my Elan for years and my carb 308 has one fitted stock.

An electric pump will keep the fuel cooler (no heat soak from the block), aids starting as the bowls can be filled prior to turning the motor, maintains more consistent pressure, helps prevent vapor lock, aids in diagnosing some engine problems, and even provides the ability to drain the fuel tank if necessary. I fit mine with a fuse and dash mounted toggle switch. Just make sure you fit one that can supply the recommended fuel pressure. Alternatively, you can fit a higher pressure one but then need a fuel pressure regulator fitted in line to the carbs.

Bill

As type26owner states, you really should need have a inertia cutoff switch. I got mine from Bean. I don't really recall the exact cost, but I don't think it was excessive. And certainly better than self immolation in an accident due to a running fuel pump.

I have had an electric fuel pump for many years. Main advantage is that it eliminates starting problems caused by vapour lock. Generally there is easier starting because you can prime the car properly. I have also fitted a make-an- break switch under the dash, and an LED on the "break" terminal so that I know when the pump is off. This actually saved the car when there was an attempt to steal it: it was found a quarter of a mile away.

I only had one failure with the old SU pump, which was fixed in five minutes at the roadside. Eventually I could not replace it with another SU, and bought some American device that runs continuously and noisily, and has let me down badly once.

I had to have an electric pump after I bought a "racing" engine complete with a sawn-off camshaft.

If you decide to fit an electric fuel pump make sure you place a fuel filter in line between the pump and fuel tank. It's amazing how much crud is in the tank.

I fitted a Facet red top without a filter and had no end of bother with the pump stopping after an hours driving or so. Read the pump manual, fitted a filter and it hasn't stopped since.

Got the pump from Demon Tweaks along with a "nice alloy blanking plate". Works fine now.

Hamish.