Pearl Engine Company

Hand Boiler Feed Pump

Now that my boiler is complete and ready to install I have to have some means of replacing the boiler water. My engine which will have a crosshead type displacement pump will be the main pump and I needed a backup in case that pump is not working. I saw that Roger Grosser of Pearl Engine Company had a new "old type" hand pump for sale at a resonable cost of 155 dollars for an all bronze hand pump complete all materials and hardware kit.. After talking with Roger and him explaining that he had purchased the original patterns for this pump. It appeared to be an easy project and will go well with my sidewheeler. On with the building of the pump.

There are probably many ways to tackle the job and this is the way I built my pump with the tools on hand in my shop. I started by drilling the 4 mounting holes for the pump body. These would later be used in a jig to do some milling.

Note: All the castings are made of silicon bronze

A real pleasure to machine and work with

The next step was to spot around the 4 holes with a 5/8" mill From here I made a piece of wood with 4 identical holes to help hold the pump body for the next step.

You can see in the picture the simple jig that was made to hold the piece while I milled the bottom flat and smooth. The nuts were taken off one by one to finish milling around the threaded rod holding the pump body. I could have just sanded the bottom on my belt sander but thought it would be better to mill the bottom.

Now that the bottom was flat is was an easy task to mount the body in my 4 jaw chuck and index it in. I'm glad I used the mill on the bottom as it was easy to setup. The casting itself was quite straight and was running within reason. I then faced off the top of the pump body as indicated on the drawings.

The next step was to bore for the packing and the packing gland. The pump body was cored and this made it an easy job.

Next was to make the piston bore itself. It figures, I didn't have a small boring bar to reach in the 4- 3/4" shown on the drawings. I made an extension for the boring tool and was able to reach in with out any problem. I like to do the bore first and then fit the piston to the finished bore. I'm glad I do it this way as I wound up being slighty over what was called for.

I finished up the body by drilling a hole where the pump arm link will mount. I will drill and tap for the gland at a later date. Now on to the piston itself. I drilled a center hole in the bottom of it so I could hold it better in my smaller lathe.

I used a 4 jaw chuck to hold the live end and a dead center on the other end. From here it was a simple matter of just turning it down to fit. When I get close I generally just make the last few cuts by taking off a .001 or less and just hand fit it. While doing this I took a break and started hand filing the pump handle and the linkage to the body. Its coming up on a holiday weekend and I hope I can sneak out to the workshop and finish  filing smooth everything so I won't have to do it after the machine work. I thought of chucking up the handle a turning that on my lathe but It was such a good casting and I wound up just hand finishing that also.

I then jumped back to the body as a friend who had my 1/4 NPT tap returned it so I could now tap the holes for water inlets and outlets. I mounted the body to 1-2-3 blocks to make sure the holes were drilled properly.  After facing off where they go in the body I drilled them out and tapped them. The cored holes where almost a perfect fit for my drill bit and I could have tapped them without drilling. I used the mill to hold the tap nice and straight.

I then sarted on the  gland that holds the packing in place. Again a 4 Jaw chuck was used to hold the gland while the outside was turned down and a hole drilled thru to use my boring bar.. It was then I remembered that I didn't have a boring bar long enough to use on my small lathe. I did an unmentionable and moved the piece from my setup on the small lathe to my larger lathe/mill. I figured a couple a thousands runout wouldn't hurt a gland for the packing,

It was easier to do this then to try and make up a new boring bar to reach in. In a few minutes I had the hole done and now to test fit what I made so far.

Well everything seems to fit fine and now all that's left to do is make three pins for the linkage and bore the holes and cut a couple of slots and I can then start to polish up the parts, paint the body and put it all together. I'm not done yet but I have a feeling its going to work just fine. 

I carefully mounted the double ended link on to a couple of blocks. I figured it would be an easy way to mill the slots at either end and then be able to rotate it exactly 90 degrees so there would be no problems later on. This method worked out very well. I sent a .375 reamer down thru the holes while they were still in the jig. The handle goes in one end and the pump body in the other end. I left these holes unreamed and will ream them when I do the assembly.  This worked out great as  I finally sent the reamer back through the double ended link into the handle and base holes while they were assembled. After all this is one of Pearl Engine's first pumps to be machined and I didn't want it to be "fitting like socks on a chicken". In the picture you can see the way I attached the two blocks and just had to turn it over after milling the slots in order to drill the holes for the pins.

For the piston slot I simply held it in my milling vise and milled the slot

To make sure I was at right angles to the slot I  used a simple jig with a piece of steel resting on the inside where I had milled the slot. It looks like I'm going to hit the steel but it has a Vee into it where the reamer is going through. Like the link,  I reamed this first and will fit the handle in place and ream as a unit. I had a little boo-boo with my setup. a piece of scrap bronze got on to the steel jig and I drilled the hole a little bit off. I will try and ream the center hole to fit my mistake. Its only about .015  off but just enough to cause a little binding. I also opened the slot up to about .010 and that cured the slight binding. Guess I'm still used to working within an 1/8" when I was doing plumbing and steamfitting. If I ever gave a fellow a measurement to a 16th I would have had a pipewrench dropped on my head by days end.

The handle itself was machined to fit the piston and link. The holes were drilled undersize and everything was fitted together. I then sent the reamer through the whole assembly. I did these one at a time and inserted the pins, In the picture it shows turning down a piece of 1/2" round stock to fit my reamed holes. They wound up just slightly under .374 to give a nice fit.

The pins were milled for the set screws as well as drilling for the cotterpins. If you check in the picture I did both these steps together so the hole for the cotterpin would be aligned with the set screw flat.  This way it would be easy find the flat spot to tightly up the set screw. I'm sure most of you have tried to find a flat spot for a set screw and wound up taking it apart to find out where it went to. No excuses for saying those naughty words now!  I wondered why both cotterpins and set screws? I think maybe back when the pump was first designed it had only cotterpins holding the pins in place. The pins probably rotated on the handle and that being smaller would wear out faster than the double holes in the links themselves. It was then that they decided to use set screws on the handle and base to keep the pins from rotating on the smaller bearing surface. This would double the life of the pump. It will probably  last 2 lifetimes instead of just one lifetime. Maybe if Roger Grosser finds some time this Winter he will count how many strokes it takes to get on the loose side. My guess would be the year it was designed squared by itself to equal 3,534,400 strokes. Let us know Roger when you get the test results.

After checking my drawings I found there was no dimentions for the gland bolts on the body drawings. No problem as its the same as the gland for the packing. Then a bell went off in my head. If I drilled the bolt holes in the gland it would be an easy job to transfer it to the body for the tapped holes. I have several pictures of an easy way to locate them. First step was to drill the 2 holes in the gland.

I then clamped the gland to the body using a small c-clamp. I then picked out the right center punch and prick punched the body.

I then placed another c-clamp on the other side and then removed the clamp and prick punched the other side.

I now had both holes located and I was confident the alignment would be correct. I also scribed the outside of the holes to check for drilling clearance on the bottom side. The drawings call for the holes to be tapped full depth. My tap just made with no room to spare.

I used my drill press for these holes as I had my combo lathe/mill apart to replace a worn crosslide nut. It would give me a chance to use my new laser edge and center finder. I bought this this past Winter at Cabin Fever from the Little Machine Shop. It works just fine and I've been using it more and more. This really made the setup easy in my drill press as I had to set it by eye and clamp the base to the table. If you look close in the picture you can see the laser reflecting off the prick punch mark. I generally use blueing for layout and the laser is quite small as it does not reflect off this type surface. The laser dot is much smaller and easier to index if blueing is used. It sells for 60 dollars and worth every penny. Just click on the picture to go to Little Machine Shop.

I'm just about done with all the machine work. I drilled a couple of holes in the piston to feed oil in to the pin holding it to the handle. Again my laser center finder was used to locate the holes. Now all thats left is to do the linkage arm

I just clamped the linkage into my milling vise and slide it into place and drilled the remaining 4 holes.
The linkage was clamped at an angle for the holes in the bottom end.  All the oil passages were relieved at the top using a 60 degree center drill. This it a little bit easier getting the oil in and gives it a finished look. So far this is the only modification I've made on the pump.

Well if it doesn't pump water it'll sure make a good boat anchor as it weighs in at 11 pounds. I never use to save the scrap from a project but I have a large can filled with good silicon bronze shavings. I think maybe I'll bring them over to the scrap yard and cash them in. I guess I could buy Roger a cup of coffee the next time I see him. That's the least I could do for producing a very nice vintage type handpump for my new steamboat. I'm sure others will want to build this very nice looking pump once the word gets out.

           Boy,  I sure hope that my boat will take all the extra pounds its been gaining lately. Maybe I should consider a diet for the Captain as he's probably 50 lbs. or more overweight. My wife really thinks its going to sink with everything I've been adding lately. In fact she just went and bought a life-jacket for the new puppy. Don't ever try and convince a woman that the dog can swim as well as the Captain and First Mate.

I choose to paint the body with my favorite green texture paint from Rust-o-leum. It the same color as my Pearl Engine. Its really a shame to paint all that beautiful bronze.

Roger furnished a real good teflon type packing. I don't just wrap it around two or three turns but make rings that fit into the gland space with a tapered overlapping end. Make sure that each joint is 180 degrees from each other. I used 3 pieces and might need another. The taper should be installed so that the gland will squeeze the taper together making it leak proof. This way you won't wind up with a spiral and have more packing on one side or ramped at an angle. It takes a little longer to do this way but I feel its worth the extra time and it seals better.

The pumps complete at this point and I have to only add the check valves and I'll check it out soon. When assembling the pump I found that the set screws furnished were 8/32 instead of 10/32 as the drawings called for. No big deal, a trip to the hardware store obtained them. While there I also bought brass cotter-pins instead of using the steel type furnished. Two 5/16 stainless steel washers were also purchased for under the gland bolts. I thought of buying stainless bolts but the ones furnished were a good grade 5 bolt. I don't think they will ever give me a problem.  Now to pipe the pump and make a base for it.

I went scrounging thur my plumbing parts for some valves, unions, checks and other parts. I found a matched pair of 400 lb. check valves and 125 lb. gate valves. I have 8 or 10 1/2 copper gate valves that I picked up quite reasonable. They are a Japanese version of a Jenkins valve. I'll give them a shot as the price was right at 2 bucks a valve. They look to be of high quality but for some reason my local wholesaler couldn't sell them. A Jenkins cost 14 bucks were these were 10 he told me. They are made by Toyo the same outfit that makes water closets and other plumbing fixtures.  Well its ready to mount on a board and go in the boat for my back up water feed pump. When I assembled it the stroke was not as required. I wound up cutting about 3/16" off the piston as the handle at bottom of the stroke was just slightly down past horizontal. The throws are now equal up and down and I wound up with 2-3/8" stroke instead of 2-1/2". I really don't see a problem except I preferred to have the throws equal. I will talk to Roger about this as there might be a valid reason as to why it was done this way. One last thing if you don't buy check valves from Roger MAKE SURE you use a good quality check valve as that is what will make the pump perform correctly. DO NOT GO WITH CHEAP CHECKS!

This is what I used:

1. A Y pattern type check as the gate is on an angle and will close easy. These type checks you can generally hear them slam closed compared with others

2. Type 200 check which is rated for 400 psi at 150 degrees & 200 psi 550 degrees.

3. A check that comes apart easy as I can almost bet you'll be cleaning one of the checks.

You could get away with a type 125 which is rated for 200 psi at 150 & 125 psi at 300 degrees. They also make a type 150 which falls in between these two. I have a couple of spring loaded checks that I will be trying out at a later date just to see how they perform.