PVf44 61 fuel pump

[arcturus]

This is really weird I have reassembled the pump as in the parts book with the inlet check valve with the bowl part facing down and the output side withe the bowl part facing inwards. A tube fitted to the inlet side and immersed in a jug of water doesn't draw in any water when the hand primer is used but does so when the tube is attached to the out put side!
Re tank that problem has been sorted and fuel flows freely from there. I need to sleep on this. The pump has been on and off so many times I could do it in my sleep.
inlet to left of pic'

[Ron Kwas]

Arcturus;

Failure to pump during testing, may be due to it not being primed, or Valves being installed wrong-way-round, or you having the Outlet submerged, thinking it is the Inlet. Clear your mind, and have another fresh look at it, presuming nothing from before!

I have also marked up your pic for flow, the way I expect it (if you first confirm the dotted connections I show).



Pump Function has two steps...starting with a relaxed diaphragm..I believe I have this right...
1. Inlet Draw: Actuating Lever is moved, diaphragm deflects, inlet draws IN fluid passed open Inlet Valve, in response to partial Vacuum created in internal volume (Outlet Valve is closed, since it only allows flow OUT, and none back in from output line, but also allowing no flow out at this time!).

2. Outlet Push: AL is released, diaphragm relaxes, and makes over-pressure in the Int Vol, and since Inlet Valve is now closed, fluid is pushed OUT passed Outlet Valve (Inlet Valve is now closed, since it only allows flow IN, allowing no flow back toward Tank).

In this way, flow in only the correct direction is possible also irrespective of AL (verifiable by blowing into the Inlet).

Hope this helps!

[arcturus]

Thanks,this is exactly as I have it.
Struggling now to replace diaphragm in body,don't have enough strength in my fingers.Finding it very difficult to hook it in straight and evenly.

[arcturus]

I'm starting to have a horrible feeling that the cam lobe has worn prematurely However on second thoughts it would still work with the hand primer. Strangely it works well on the bench but not on the car!

[arcturus]

Having gone through all of the variables i am now leaning towards the idea that the actuating lever which runs on the cam could be the problem.Quite possibly worn which is preventing it being raised high enough to operate properly. Will possibly need to fit an electric pump. What pressure pump?

[Derek UK]

Beware that when you fit the pump you don't insert the lever the wrong side of the cam. Been there, done that. When leaning over the wing (Amazon) the pump is fitted at arms length so positioning is less easy. The position of the cam may not be in your, or the pump arms favour. I was doing it in the dark many years ago on my B16 Amazon, I'd put it in wrong, and when I straightened up found a policeman standing behind me. They used to wander around on foot back then. Made me jump, but he helped me out with his torch.
If you have the original B16 glass top pump, the pump lever, when the pump is fitted, will move the diaphragm less than when you move the pump main lever. I said that fitting the diaphragm rod to the lever was a pain (seal damage) so just be patient with it.

[arcturus]

Thanks for that Derek.I'm pretty sure that the actuating lever is sitting on the cam as it should be,I can feel the upwards pressure on the lever as I fit the pump into position. It's just so strange that the pump stopped working 20 km from home on the road.It's a pity that I can't get an original lever to compare wear with.Having said all that I'm mot averse to fitting an electric pump in a discrete position and keeping the originality appearance by leaving the mechanical pump in situ. Time will tell.I have a mechanic friend come over at the weekend to assist.I'm not too proud to ask for help.

[Clan]

Originally Posted by arcturus

Thanks for that Derek.I'm pretty sure that the actuating lever is sitting on the cam as it should be,I can feel the upwards pressure on the lever as I fit the pump into position. It's just so strange that the pump stopped working 20 km from home on the road.It's a pity that I can't get an original lever to compare wear with.Having said all that I'm mot averse to fitting an electric pump in a discrete position and keeping the originality appearance by leaving the mechanical pump in situ. Time will tell.I have a mechanic friend come over at the weekend to assist.I'm not too proud to ask for help.

The mechanical pump is a lot more reliable and neater than an electric one, I would persevere and get it working again .

[arcturus]

If it turns out to be a worn actuating lever I could have the bearing surface welded up to a higher profile but would that have an adverse effect on the cam?I would only see that as a position of last resort.

[Clan]

Originally Posted by arcturus

If it turns out to be a worn actuating lever I could have the bearing surface welded up to a higher profile but would that have an adverse effect on the cam?I would only see that as a position of last resort.

Im sure those pumps will be available from a specialist if not volvo themselves , worth trying ...