Mine runs 4-6 psi, it is similar to the impulse type Facet electric fuel pumps. In cold weather, I generally have a 5 - 10 psi pressure drop from the electric fuel pump to the IP. This can cause fuel starvation and I plan to install a Holley Blue fuel pump when one becomes available.

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I am interested in this for use with alternative (thicker) fuels, vegetable oil, etc. Would this affect your choice of pumps?

Most definitely, the pumps need to be able to operate with a more viscous fuel, or deal with higher fuel temperatures. Some pumps may be available with optional Viton seals.

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Primer pump o-ring? Is that internal or external to the pump? Mine leaked fuel out and air in when I used it. Would a new o-ring maybe fix it? I put the new upgrade primer pump on mine, one of the few new parts I have bought.

I also invested in the new primer. Sure is a cleaner way to prime the fuel system. To install it, I removed the lift pump from the engine. This made it much easier than when I did the one on My Wife's car. Just 2, 10mm nuts and a rag to catch the oil drips. 10 minutes and it was back on the engine.

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Tony from West Oz.
Fatmobile 3 84 300D 295kkm Silver grey/Blue int. 2 tank WVO - Recipient of TurboDesel engine.
Josephine '82 300D 390kkm White/Palamino int.
Elizabeth '81 280E, sporting a '79 300D engine.
Lucille '87 W124 300D non-turbo 6 cylinder OM603, Pearl Grey with light grey interior


Various parts cars including 280E, 230C & 300D in various states of disassembly.