Does anyone have the technical manual for maintaining this steam stoker motor? One of our mechanics is tearing down the unit and cleaning up the damage caused by exposure to weather. Please contact us off-board, either by PMing me or emailing newenglandsteamcorp@gmail.com .

All assistance is appreciated. We've had a spectacular 2018. Here comes 2019!

This is a Standard Stoker Company HT-1 stoker system with a two cylinder 5"x5" steam engine driving it. The goal is to first make the engine operarational. I have the catalog descriptions and parts list with drawings. What I really need is servicing/rebuilding literature. Must be a shop manual out there somewhere....
Bearing clearance specs, fastener torque specs, bore to piston fits, valve fits etc.
The crank is running on roller bearings and with the short stroke I imagine this is considered a "high" speed engine.....anyone know the rated rpm is? or hp?
Valve gear is fixed with an external steam valve as throttle and reversing the steam direction to reverse.
Any guidance on the engine or the stoker system is appreciated.

Bob D.

It's the same as a 7 X 7 DS except the distance from the face of the valve to the face of the valve chest bushing should be 1 3/8" with the valve in its extreme outward position and 2 1/2" with the valve at its extreme inward position. I will send you what I have when I get a chance to copy it.

We're looking at an HT-1 stoker. Thank you to the folks in Minersville, Pa. for some data we are using. Thanks to the few of you who located Stoker Company booklets. We need the detailed technition's repair manual.

Here is what I have:

The Standard HT Stoker

Lightweight medium-capacity stokers for application to smaller locomotives have been developed by the Standard Stoker Company, Inc., and are designated as the MB-1, BK-1, and HT-1. Each of these stokers is patterned after the larger models and possess the features that are characteristic of the larger stokers.
The screw for elevating coal to the distributor is housed within a tube termed the elevator pipe which is substantially straight along its axis and is declined rearwardly from the lower part of the fire door opening to a point beneath the cab deck.
The tender conveyor unit is a duplicate of that used for the MB and BK stokers. The distributing unit is of the type using steam jets for distributing coal over the fire bed. It is of different construction than those used with the MB and BK stokers. The elevator screw extends almost to the top of the elevator pipe and delivers coal, in free and loose form, to the distributing table. The jet plate, together with the adjustable vanes in each side of the upper end of the elevator pipe, provide the means of controlling the distribution of coal.
The jet system employs high and low pressures for independently controlling the distribution of large and fine coal. The jet has five cored passages suitably drilled for distributing the coal to all parts of the firebox. The distributing table extends forward from the jet plate and its upper surface has ribs forming channels through with the fine coal is blown forward by the bottom or low pressure jets. The larger coal rides over the ribs and is carried forward by the double row of upper or high-pressure jets. The two corner holes located on each side of the jet plate, in conjunction with the curved ribs on the distributing table, effect the distribution of coal to the back corners.

The Standard 5" X 5" Stoker Engine

The 5" X 5" stoker engine used on the smaller Standard stokers is a double-acting, two-cylinder, variable speed, reversible steam engine, designed to operate with either saturated or superheated steam.
Maintenance: Maintenance of the 5" X 5" engine closely follows that for the 7" X 7" engine. Except for minor improvements over the DS engine, the 7" X 7" is of the same design as the DS engine in connection with the MB stoker. Under ordinary conditions and with proper care and lubrication, the stoker and stoker engine will run from shopping to shopping of the locomotive without any repairs, except possibly the packing of pistons or valve stems and the occasional keying up of the crank ends of the connecting rods.

I have to go to work. The next installment will cover Packing Piston and Valve Stems, Connecting Rod Adjustment, Eccentric Rod and Cap Adjustment, Renewing Valve Rings and Checking and Setting Valves.

Thank you, Adam. The data we are searching for details the measurements, tolerances, and all the jazz for keeping her healthy and in sound condition. The #55 manual is in our files. We are looking for the maintenance manual.

Not sure what you're looking for beyond Packing Piston and Valve Stems, Connecting Rod Adjustment, Eccentric Rod and Cap Adjustment, Renewing Valve Rings and Checking and Setting Valves. These ARE the maintenance.

Best of luck.

To quote Bob D. "What I really need is servicing/rebuilding literature. Must be a shop manual out there somewhere....
Bearing clearance specs, fastener torque specs, bore to piston fits, valve fits etc."

I don't know, Richard. Most of what I've worked on weren't laid out in a table of measurements - you fit bearings to oil clearance, grease clearance or dirt clearance depending….. try to keep the pistons to within a 32nd of the bore, valves likewise. Bolts on steam get tightened as tight as you can get them and then just a little bit more. It's more a feel sort of thing based on experience. It's also pretty forgiving, nothing like a Swiss watch. If it doesn't bind, run hot or clank much you're probably fine.

Exactly what Dave said. My literature uses terminology such as "The brasses may then be reduced in the usual manner" and "When replacing, adjust the keeper nuts correctly, making sure that they are securely tightened". Do you think a torque wrench ever touched any stoker engine? Make sure you measure between the marks on the valve stems and valve rods before you remove the valves. If they're not the same or really close when you put it back together, you should investigate why.

Good luck.

Adam, would you be willing to post your data anyway? I don't think those guys are hearing what you are saying. I'm just curious what is there, and it would be good to have it available for others doing a search at some point in the future. Thanks.

Packing Piston and Valve Stems

There are inside-packed and outside-packed arrangements for valve and piston rod packing. The HT is outside-packed. The stuffing boxes are located in the space between the back cylinder wall and the front wall of the engine bed. In this location they are readily accessible, and they can be adjusted and repacked without removing the engine bed cover. A castellated gland nut is seen in the photo above. Outside-packed engines use semi-metallic packing on both the valves and pistons on both cylinder block and engine bed sides. Use an appropriate sized spanner to loosen the gland nut, slide it back on the rod, remove the old packing, install new packing and tighten. (Keep in mind things expand after warming up so don't overtighten initially - tighten to stop leakage). To remove a gland nut completely, you will have to unkey the rod and pull it. There are still commercial metallic packing companies out there and they will make whatever size you ask for.

Connecting Rod Adjustment

(You stated your engine has roller bearings - likely a late retrofit so disregard this)
The bearings in the back end of the connecting rods are fitted brasses. If necessary to reduce them, remove top nut on the key keeper, remove the key and slide the strap back. The brasses may then be reduced in the usual manner. When replacing, adjust the keeper nuts correctly, making sure that they are securely tightened.

Eccentric Rod and Cap Adjustment

Shims are provided for the adjustment of the crank ends of the eccentric rod and cap. When necessary to take up lost motion, remove the cap end and remove enough shims to compensate for wear. When replacing caps, be sure the nuts are securely tightened and that the cotter pins are in place.

Checking and Setting Valves

Remove the valve chest cover. Rotate the crankshaft until one of the valves has moved to its extreme outward position in the valve chamber. The distance from the face of the VALVE to the face of the valve chest bushing should measure 1 3/8". The crankshaft should then be turned until the valve is at its extreme inward position. In this position, the distance from the face of the valve to the face of the valve chest bushing should be 2 1/2". This procedure should be followed with both valves. If the valve travel does not come within this limit (or pretty close to it and even on both sides), check for lost motion. If lost motion is found, it should be eliminated and the valves set as above. If no lost motion is found, or if after taking all lost motion the above distances are not obtained, it will be necessary to adjust the valve stem in the coupling.

Renewing Valve Rings

Before disconnecting the valve stem, set a pair of dividers to the marks on the valve stem and valve rod. Measure the distance between the divider points and write it down for each valve. Then slack off the valve stem locknut, screw the stem out of the clevis and pull the valve out of the valve chamber. The valves are of the built-up type similar to the locomotive piston valve. After the valve has been removed, take off the front nut, separate the valve, renew the rings, and reassemble in the usual way. When applying, see that the points of the dividers drop into the marks to which they were previously set, otherwise the valves will be out of adjustment.

Renewing Piston Rings

Draw the piston rod key, remove piston and rod, and apply rings in the usual manner. (remember to offset the gaps)

I am of the opinion that the above information is as technical as one will ever get on a stoker engine. Set your lubricator to 2-3 drops per minute during operation.

Good luck.

Thanks for all the replies.
I guess that my biggest concern was the piston to bore fit limits. I have info on the 5"x5" with .005"-.008" clearance to a max of .020" with standard rings. Catalog parts listings show rings 1/32" oversize for standard pistons so that would be .03125" + (.020" limit?) clearance.
The pitting of the bores I believe will clean up within .020" -.030" so I should be ok with oversized rings fitted to standard pistons. I'd rather not make oversized pistons...
When I mentioned ball bearings that is just on the crankshaft mains.
Has anyone measured these or know a modern bearing number replacement? That and the two crank seals? They look felt but I would think a modern lipped seal would work ok.
Probably neither the bearings or seals have to be replaced but just curious what options are out there.
I get the rod cap fits and adjustments. Cap nuts need to be tight and then brought to the nearest hole for the castellated nuts. There was quite a difference between the fastener tightness between the two piston rod caps.
Does anyone know if the piston and valve packing assemblies need to be removed before the cylinders are unbolted and removed? I don't see a lock screw for the packing base like on the 7"x7" engine. I believe the threads are in the block and not the cylinder casting.
Haven't parted the piston rod taper to crossheads yet. Was thinking of making up a jacking screw whose nut is a slug that replaces the wrist-pin. Load it up and whack it. Maybe a little heat on the crosshead first to warm it up. Not really sure what it will take to seperate these.
Just starting this project, in the disassembly/inspection cleanup aspect.
If there is interest I can post some pics of progression.
Just got to remind myself it's not a performance infernal combustion engine........

Does anyone know where the crankcase oil level was to be maintained? To the plugs partway up the block side? One of them has a small petcock. What oil for the crankcase?

Thanks,
Bob D.

Try peening the rings on the OD to give them a touch more expansion and then if the gaps aren't too wide they will go for a very long time.......

Most of the sump oil levels are to the fill plug opening on old stuff, but never worked on a stoker engine.

Probably somebody did a partial disassembly and then threw it all back in the distant past for reasons now unknown, not bothering to completely torque the nut down. I've seen such things on cylinder heads - one on very tightly, the other just a little more than hand. Somebody wanted a look at something way back when.

Douse the wedges with PB and let them set for as long as feasible - heat does wonders, and loading followed by percussion if the load doesn't squeeze them loose is a very good thing. You're on the right track. Best wishes.

Bob D. - a few years ago I sent Dick G. a Marks Mechanical Engineering Handbook from 1924, the same year the 470 was built. It was my hope that the 470 restoration team could get from it an idea what standard practice, in the various mechanical areas, was in those days. So for instance, if literature from various locomotive appliances said to do something "in the normal manner," the team could find out from the Marks Handbook what "the normal manner" was, like bearing clearances, etc., etc. It is a small, very thick book like "Machinery's Handbook" is now, so I'm sure there is a lot of information detailing how things were done in 1924.