TheHaflinger.com

Anything better than a 12v Facet 2-4 psi pump? Or even lower pressure?

Use some thing like 1.5-2.5 PSI as the original and probably still the best option, the original mechanical pump wouldn't have managed much more.

John

You can get a 1.5-2.5psi pump at Autozone/pep boys/or Oreilly's for around $50.

Yep, probably what I'll be doing, Jim. I'll probably pull the old electric pump that's there, wire up a fused relay and replace it with one of the Facet style pumps...or whatever I find that's available.

What's under there now:

A dumb question, but what is the benefit of an electric pump? Is there more to it other than merely speeding up the initial starting from cold?

There is that, but for me it's just easier to source than a rebuild kit for the mechanical.....

There certainly isn't a good case for doing it purely on efficiency. Converting mechanical rotary energy in to electrical energy has losses, then converting it from electricity into mechanical energy again adds to those losses. The original mechanical pump only has to overcome friction losses and if looked after, those would be minimal.

With an operative non return valve in the system, there is no reason for the pump to have to "prime" the carb unless you are talking long periods of inactivity giving time for the fuel in the carb to evaporate.

Have you taken the original pump off and blanked the hole? if not then it is still pumping air - even if inefficiently!

John

The history on this truck is spotty, and I'm finding out new things as I go along. I don't have any good data on what's been done to it, so as I get into it....repairs.

What I was told, and Jim L. can correct me if necessary, is that the original engine was blown, and this is a Puch 650 from a car. Completely civvy, except for bits like the ignition and electricals. No governor on it either. I'm sure that when Jim installed the motor, the hole was plated off.

The electric fuel pump has been on it for a long time, but luckily it's still being made...it's a Hüco 030 3010 that puts out 0.15 bar, about 2 psi, which should be perfect, so I'm going to look into a rebuild kit for it.

From what I have been too the mechanical pump can eat up an HP+ and considering how few we have an electric pump can give a bit back.
Please correct me if I am wrong
Dan

I can't see how the mechanical would eat up more than a small fraction of the total output, not enough to notice in the larger scheme of things.

Well, looks like getting parts for that Huco pump, even though it seems to be a very nice unit, is impossible. So I'll probably just go with one of the Facet style....off to the parts shop!

I doubt there is any definitive proof of how much power a mechanical fuel pump uses compared to an electric one. The other big issue with an electric pump is teh Dynastart only just covers the electrical requirement of a haflinger, particularly the early ones which have a lower output Dynastart to start with.

Dynastart's have a quoted power output, but output drops as they warm up so you should be careful about how much electrical load you put on it.

John

That pump was fitted by the Swiss, very common find on Swiss Milspec units. Looks like the pump cover gasket has shrunk.
When they added the electric pump, they installed a block off plate that holds the pump lever secure away from cam.
No need to crank to fill carb, faster starting, more reliable(if it leaks it does not fill crank case with fuel) and it is mounted under the center of chassis for easy service.
The circuit is already protected by the breaker on dash(8A).(coil power)

I have one of these fitted to my Haffie - http://www.ebay.com.au/itm/Electric-Uni ... SwgQ9V2Anm and given the price I have a second in my spare parts. They work well and are very reliable. This one does not have the pressure to push past a closed carby float. When back pressure builds up they switch off.

The main advantage I found over the mechanical pump was when I was having carb problems and it was flooding - I have a connector in the power line to the pump so just switched off the pump while cranking the engine to clear the flood - with a mechanical pump it would just have keep pumping.

The other advantage is that you could mount it up near the tank if you wanted to prevent fuel vaporisation in the fuel lines but even with our local high temps in summer I have never had an issue with mine being fitted in the engine bay (near the voltage regulator).

If your happy with the mechanical pump then stay with it. My Haffie came with the electric pump and it works great for me.

Garry

Goatwerks wrote:That pump was fitted by the Swiss, very common find on Swiss Milspec units. Looks like the pump cover gasket has shrunk.
When they added the electric pump, they installed a block off plate that holds the pump lever secure away from cam.
No need to crank to fill carb, faster starting, more reliable(if it leaks it does not fill crank case with fuel) and it is mounted under the center of chassis for easy service.
The circuit is already protected by the breaker on dash(8A).(coil power)

Ah, now that's good to know. I might break it open to see, and if it's just the cover gasket I can probably deal with that. Diaphragm, not so much.

I just came back from three parts shops here, NAPA, O'Reilly's, and VW Paradise - all of them carry the 4 psi Facet pumps. I'm going to look into bringing in a couple/three of the Huco units, might not be a heckuva lot more expensive, and they've got some nice features.

in hot weather , with a hot motor , the fuel evaporates from the carby quicker than you think it could .
with electric pump turn the key , wait for pump to stop .

also good if you run out of fuel .
vroom vroom .

kerry

OK, found a 1.5-2.4psi Facet pump from Aircraft Spruce. Haven't heard back from the Huco supplier yet...they're UK.

Did you contact these huys?

http://www.gowerlee.dircon.co.uk/HUCO.html

The pumps are actually made by a German company so the UK contact is only an supplier / agent.

John

I use this one with no issues
http://www.amazon.com/Mr-Gasket-42S-Ele ... B000BWE4RC

Just got the response back from the UK guys, works out to be 170.00USD for two, shipped. Pricy...have to think about it. Heink - I'll give gowerlee a try also, see if their pricing is different.

Tech - what carb are you using on your truck? Is it a Weber?

I live in the automotive backwater of the world and can get these sort of pumps at my local auto parts suppliers - if not in stock will arrive the next day.

In West Coast USA - automotive heaven - I am not sure why it is so hard to find something suitable.

Garry