Coalbrookdale house pump
When I moved into a house at least 40 years ago I found the body of this pump in the garden. There was no cap, lever or mechanism. Some years later, when digging out an old bottle bank, I uncovered part of a piece of something which looked as though it could be the end of the pump lever. Much to my delight, further digging showed it to be the missing parts of the pump. As far as I can see it is identical to the 3" no 8 "Improved House Pump" shown in the 1875 Coalbrookdale catalogue: The catalogue page can be seen at http://www.darwincountry.org/explore/002496.html which I discovered after browsing the Village Pumps website ( http://www.villagepumps.org.uk/ ).
Considering its age, it's in remarkably good condition - naturally there is quite a lot of pitting. Part of the arm which provides the pivot bracket for the pumping lever has broken off and has had a competent blacksmith's repair - I'd guess at least 60 years ago. Apart from that the cast iron is not cracked or broken. There is no leather washer nor brass part of the upper clack valve as mentioned in the Coalbrookdale catalogue (there are 3 steel washers, presumably, fitted as a replacement). There is no lower (foot) valve. The bore of the cylinder is corroded and needs to be rebored or lined.
The cap and lever bracket is a separate component so they, and the handle, can be rotated about the body to provide a convenient working position. They are locked to the body by the screw at the bottom of the lever bracket.
We moved house twice since then and taken the pump with us. I've always hankered
after getting it working but
the old dragon my wife has always
resisted. Finally she has relented so I've now started work on it.
Updated - 7th October 2009
Neither Dick Williams of Village Pumps nor I could fathom out how the original plunger comprising upper clack valve and washer were configured. Initially I was going to make a new one from scratch but, when Dick gave me a link to W. Robinson & Sons, I saw that they sell one for a 75mm bore pump in much the same style as could have been made in Victorian times so I decided to go for that.
Plunger (050-11015) for 75mm bore pump bought from Robinsons
( http://www.pump.co.uk/shop/Garden/GardenHandPumps/d33/sd6 )
The valve, which is upside down in the pic, has a machined conical facing to match the seating machined in the top of the component on the left. Because the valve is not positively guided it can tip which allows some seepage but that doesn't matter as the only time that it needs to seal fairly well is while the plunger is upstroking. Any seepage occurring then is trivial in comparison to the volume of water displaced. It's more important for the foot valve to provide a good seal but, even if it doesn't, it's not a major problem provided that the pump self primes: it simply means that a few initial strokes will be needed to prime the pump if it hasn't been used for some time.
Apart from the difficulty or expense of boring out the pump body to obtain a smooth finish it would have ended up much too large for the new plunger so I decided to line it with standard copper pipe of 76.1mm OD with wall thickness of 1.5mm, i.e. the bore is 73.1mm - Coalbrookdale offered a copper lining as an extra. Copper pipe of this size is incredibly expensive to buy from plumbers merchants as it comes in 3 metre lengths; I posted an ad. on http://www.homeworkshop.org.uk/ and someone replied offering just what I wanted at a sensible price.
I soaked the new washer, made out of leather about 1/4" thick, in olive oil in the hope that it would be OK in that bore, however there is a very competent leather worker in our village who can make me a blank out of thinner leather. Incidentally there's an article (but with lots of errors and omissions) about making leather cup washers at http://www.lifewater.ca/Appendix_L.htm.
Seemingly there's more to leather than meets the eye. Clayton of Chester describe several types of industrial leather on their website ( http://www.claytonleather.com/indleathers.htm ). If want to know what sort of leather you need to make a reptile glazing bolster then they are just the people!
The new cup washer wouldn't go into the copper pipe so I decided to make a new one out of 3mm (1/8") thick leather. That needed a forming tool to shape it which I made.
Washer forming tool
I thought that I would try reforming the thick washer in the tool; it worked OK so there was no need to make a new one.
Because of scaly corrosion in the bore of the pump body it was undersize in places to fit the copper pipe. I tried cleaning it up as described by Julian Worskett in http://www.jwdltd.demon.co.uk/wellpump.htm but the scale was extremely hard so I made a rig to bore it out.
Boring was done with the pump body upside down holding the body in a large old lathe chuck.
As there is a large volume above the discharge spout there is no need for the cap of the pump to be sealed to the body.
The "boring head" is actually a crappy face mill that is commonly supplied with Asian mill drills and is not intended for boring (and not much good for face milling either). The head was mounted on a 1 1/4" dia. shaft with a T handle at the top. The bore of the MDF was a running fit on the shaft and ensured that it was aligned with the axis of the pump. As supplied the face mill would bore to just under the required size but, by shimming under the inserts, it could be adjusted for size. Because of the rake of the tips it tended to feed itself into the cut and jam. The feed was controlled by an adjustable stop: coarse adjustment was by the position of the hose clip on the arbor. Fine adjustment is by the adjusting nuts. For each rotation of the arbor the adjusting nuts were rotated half a turn giving a feed of just under a millimetre per turn.
After boring the copper tube was light push fit in the body of the pump and was sealed to it with waterproof silicone mastic.
(Cap locking screw circled)
Dick Williams had expressed concern that, because of the knuckle joint, the plunger would cock over on the downstroke but I hoped that, because the washer was nearly an inch high, it wouldn't - Dick was right - the top part of the plunger would have gouged the copper so I made a guide out of polypropylene that fits to the bottom end of the connecting rod and is a clearance fit in the tube.
Dick suggested that I made the lower clack valve as a "C" valve out of sheet neoprene but, as Robinsons sell filter foot valves quite reasonably, I took the easy way out and bought one. I made a plate out of 10mm mild steel to match the base flange of the pump with a 1" BSP central tapping. It seals to the flange with a rubber gasket made from an old inner tube from a tractor. A suitable length of 1" galvanised pipe will be screwed into it and the foot valve fitted on the other end.
So far I've only tried it lifting about 5 feet. It self primed without any trouble and pumps well. Now it just needs to be painted and installed.
Original clack valve body is after skimming its top face - about 0.080" removed. The square hole is tapered; the red arrow indicates the tapered square section of the shaft. Presumably the steel washers were fitted as an alternative to an original brass plate. (Note that steel is far more prone to corrosion than wrought or cast iron). Presumably the collar on the shaft served some purpose - possibly there was disc of some sort to prevent the plunger from tipping over i.e. acting in a similar manner to the guide that I made. What was the taper for that couldn't have been done with a shoulder and why was it square?
Clack valve body - Upside down
Note that there could not have been a cup washer surrounding the body as there is only about 0.04" clearance between body and bore
Presumably the "3" refers to the nominal bore of the pump