Club 80-90 Forums

Weak fuel pump which doesn't have the stamina to suck fuel from tank when line is dry.

CovKid wrote:Weak fuel pump which doesn't have the stamina to suck fuel from tank when line is dry.

I was thinking something wrong with the suction yesterday too, as I manually sucked fuel up to the pump and it still wouldn't start.
Unfortunately the battery started to lose `umph` at that point after a few attempts, so I put it on charge.
I wanted to start from a good charged battery and see if fuel is getting pumped up while cranking as per Itchy's advice above.

My charger said batt was low at 20% on the scale on the side when connected.

Left it on all night and half of yesterday, but it still shows 20% this morning, although shows it is charging....

Should a battery take days to charge?
Does that sound like an excessive amount of time to still be on 20% charge?

I have two chargers, and the original still showed 20% yesterday before I went to work, so used another I have.
( They won't both be faulty - one has only been used a handful of times. ) It still shows 20%..!!

Ordinarily I would think the battery was dead, but it's less than 6 months old.

It's a Yuasa 71Ah and 650A sealed unit.
None of my other batteries have taken this long, but they weren't sealed batteries.
( Charger is set to `sealed` battery charging. )

Update.

Put different battery in and got misses to crank over.
No fuel comes through the pump

There are some for £13 online. Are they any good?

take pump off and press lever manually
then check length of pushrod

itchyfeet wrote:take pump off and press lever manually
then check length of pushrod

OK.

I have the pump off - lever on bottom has good spring action.
How long should push rod be?

when you pump the lever does petrol come through or not?
if pipe is empty you may have to pump it many times to pull fuel through.
pushrod 100mm, sticks up past spacer 4mm

Cheers Itchy.

I will have to reconnect it to the fuel lines to test if fuel is pumped up when operated manually - I took it right out and brought it in the house.
Tomorrow job now in the dark.

I will update you with some results.

Cheers.

Smiffo, with a fully charged battery and aircleaner pulled off top of carb, pour say an oil capful of petrol straight down carb throat. Now try to start engine. It should splutter begin to run then die. Repeat process until pump is able to pull fuel through on its own. You can't get the pump running fast enough on starter alone when line is dry. If this fails to sort things, you can then concentrate on pump. I prefer an electric pump now, but mech pumps generally give many thousands of miles of trouble free service. However, as they age their ability to prime the line from scratch gradually diminishes. You just have to help it a bit.

Thanks CovKid.

I did try that initially, as it was the trick I had to use back in July when the van was stood up for a few months.
I have also tried pumping it manually as suggested in this thread - still no joy no fuel comes through, but I can suck it from the tank to the pump easily enough..

I am going to order a new pump today or tomorrow.
I will keep you updated.

Beware I think new some pumps have one pipe of larger diameter, means you will need to adapt the pipe.

https://www.brickwerks.co.uk/index.php/ ... -3153.html" onclick="window.open(this.href);return false;

I wouldn't buy cheap, it's just not worth it.

this looks same diameter both sides but best check with them.
https://www.vwheritage.com/shop/type25- ... tartRow=14" onclick="window.open(this.href);return false;

think this is same, 2x6mm pipes
https://www.brickwerks.co.uk/index.php/ ... l-wbx.html" onclick="window.open(this.href);return false;

itchyfeet wrote:Beware I think new some pumps have one pipe of larger diameter, means you will need to adapt the pipe.

https://www.brickwerks.co.uk/index.php/ ... -3153.html" onclick="window.open(this.href);return false;

I wouldn't buy cheap, it's just not worth it.

this looks same diameter both sides but best check with them.
https://www.vwheritage.com/shop/type25- ... tartRow=14" onclick="window.open(this.href);return false;

think this is same, 2x6mm pipes
https://www.brickwerks.co.uk/index.php/ ... l-wbx.html" onclick="window.open(this.href);return false;

I may have dropped off here then - I went for the one in your first pic before reading this....
The fuel lines were minging too, so ordered some of those for feed and return pipes, but now wondering if it might not all fit...

Either way, I will find out soon enough.!!
I will keep the updates coming here - to make sure people don't follow my mistakes, if nothing else..

Hi, I think you commented on my thread with similar issues.

Get a push rod at the same time and change it over, they're only about £3 and solved my problems and that was after swapping two new fuel pumps (one with the larger bore outlet I ordered by mistake and now on e-bay).

Old push rod comes out easy, just grab top with pliers, mine had lost its rounded end and was about 2-3mm shorter overall.

For £3 it got to be worth swapping at same time.

(worth noting I put my old fuel pump on with new push rod and van ran perfectly so it was the rod)

Ecopod wrote:Hi, I think you commented on my thread with similar issues.

Get a push rod at the same time and change it over, they're only about £3 and solved my problems and that was after swapping two new fuel pumps (one with the larger bore outlet I ordered by mistake and now on e-bay).

Old push rod comes out easy, just grab top with pliers, mine had lost its rounded end and was about 2-3mm shorter overall.

For £3 it got to be worth swapping at same time.

(worth noting I put my old fuel pump on with new push rod and van ran perfectly so it was the rod)

I did exactly that EcoPod - remembered your post - saw the rod for £3, and thought "why not?" even though I really think it's the pump, you can't go wrong for an extra £3, can you?

Alternative is to go electric. Cost is about the same. I quite like electric though as you can hear the whole fuel line prime. Great if you're unfortunate to run out of fuel - no more coaxing it to fire up.

CovKid wrote:Alternative is to go electric. Cost is about the same. I quite like electric though as you can hear the whole fuel line prime. Great if you're unfortunate to run out of fuel - no more coaxing it to fire up.

Hi Covkid.

What pump did you use, how is it wired and what did you do with the redundant space that the mechanical pump sits in?