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Fuel pump
Posted: 25 Jul 2016, 14:09
by burnzdog
Stupid question, where is the fuel pump on my 81 Aircooled 2L CU? Not getting any fuel from the tank at the moment. Just wondering does the tank have a pump?
Re: Fuel pump
Posted: 25 Jul 2016, 14:27
by Fudgy666
Kinda depends if you still have the original mechanical pump, or an after market electric pump.
I have an electric pump and it is under the van screwed on to the chassis around 30cm-50cm from the fuel tank.
There should be an in-line fuel filter before it too.
Can't really help you with the location if it's a mechanical pump, but It's in the engine bay.
There isn't any pump in the actual tank.
Re: Fuel pump
Posted: 25 Jul 2016, 14:33
by bigherb
If you still have the original mechanical pump it is mounted onto the side of crankcase underneath the engine on the front right hand side.
Re: Fuel pump
Posted: 25 Jul 2016, 15:24
by burnzdog
The carbs were changed this year, the fuel line comes in at the front of the engine bay, so i dont think its connected to anything. Could it be there is no fuel pump?
Re: Fuel pump
Posted: 25 Jul 2016, 15:40
by CovKid
Er no. Scrabble underneath and you should find it. Its behind what you're looking at

Re: Fuel pump
Posted: 25 Jul 2016, 16:38
by bigherb
It would be mounted here where the blanking plate is on mine.

Re: Fuel pump
Posted: 25 Jul 2016, 17:15
by burnzdog
Sorry found it.... is there much i can do with it?
IMG_20160725_175128.jpg
Re: Fuel pump
Posted: 25 Jul 2016, 18:52
by bigherb
The inlet hose look a bit wet check it is not split and allowing the pump to suck in air.
Check the pump pushrod is not worn it should be 139.8mm.
Check there is fuel coming out of the tank and the pipes are not split and the filter is not blocked.
Re: Fuel pump
Posted: 25 Jul 2016, 20:49
by CovKid
Looks like a 'fuel line overhaul' is needed too. Get some good quality replacement hose and proper fuel pipe clamps (not jubilee clips). Check hose from tank to pump and pump to carb/s
Re: Fuel pump
Posted: 25 Jul 2016, 20:54
by burnzdog
Nothing coming out the tank, I'm assuming the fuel should come out atleast to fill the filter up which is currently empty and is 20cm from the tank?
bigherb wrote:The inlet hose look a bit wet check it is not split and allowing the pump to suck in air.
Check the pump pushrod is not worn it should be 139.8mm.
Check there is fuel coming out of the tank and the pipes are not split and the filter is not blocked.
Re: Fuel pump
Posted: 25 Jul 2016, 21:25
by CovKid
Make sure theres enough fuel in it for starters then try removing pipe from filter and blowing back into tank - could just be crud up against the outlet inside. Your pump could well be foobarred but start checking along the line first.
Re: Fuel pump
Posted: 26 Jul 2016, 11:38
by burnzdog
If the pump has gone which pump is best to install and where should it go?
Re: Fuel pump
Posted: 26 Jul 2016, 12:16
by burnzdog
Anyone used one of these ?
http://www.machine7.com/product.php?xProd=463" onclick="window.open(this.href);return false;
Re: Fuel pump
Posted: 26 Jul 2016, 13:59
by CovKid
Several of us (including me). Best thing I ever fitted in terms of reliability. Lookup 'Facet' in search box, top right. Proper way is with an electric fuel pump relay, second is powered from blue wire from alternator. I confess mine runs straight off ignition now, which technically isn't right but prefer knowing the line is full before I start her up - you can hear when it is by the change of note.
Essentially you fit it close to tank underneath and after fuel filter. You could just cut hoses on your old pump and blank those up.
I had endless problems with engine dying unexpectedly and rough running before I changed to an electric one and to be honest, pound for pound, its the best and possibly only solution on your engine. Not had to buy a mech pump for one of those engines in some years but I believe they're practically extinct now.
The one thing you DO need to bear in mind is that the extra pressures involved mean that fuel hose has to be well fitted, good quality clamps etc so no chance of any coming undone. Also float level needles in some carbs can work fine with a mech (suction) pump but not be able to handle the extra pressure of an electric (push) pump and may need replacing if you get flooding problems. A carb overhaul kit sorted mine.
Nowt wrong with mech pumps though. I'm a big fan of them - when they're working well. Electric ones just give better peace of mind and cost the same or less than a mech pump anyway. £45 a bit much though - you can get a low pressure Facet for about £30 on ebay.
Machine7 is in same town as me - often handy.
Re: Fuel pump
Posted: 26 Jul 2016, 15:11
by burnzdog
Thank Covkid
Found your thread
https://club8090.co.uk/forum/viewtopic.php?f=39&t=134581" onclick="window.open(this.href);return false;
Interesting. Id like to at least try and correct the issue with existing pump to use the bus at the weekend.
A question on the existing pump, I can see the in/out fuel line but there is a third connector that disappears behind tinware, what does this do?
Also, is there anything you can do with a filing pump apart from replace?