Mery Explosive Engine

[oldengineguy]

1089 shows the cam gear. Drawing calls for .281 dia. shaft with 1/16 key. I do not have a 1/16 broach so silver soldered a bushing to the shaft then turned to 1/2in. and machined for an 1/8 key which I have a keyway broach for. Kit includes casting for eccentrics ,however it was easier to make these from bar stock. 1091 & 1092 are machining the eccentric straps ready to bore and relieve for locating rib. 1093 is the set-up on face plate to bore the inside diameters of the straps. 1102 shows he set-up to drill the holes in the frame to mount the cylinder. 1103 is the drill guide with holes to locate cyl.-base and cyl.-head joints which are different bolt circles.1105 is the set-up in the lathe to machine the back face of the frame where the cylinder bolts on. This was "tense" machining with no room for error with the mount foot rotating so close to the tool. I put a bar on the ways between the headstock and carriage as well as the clamp -on stop to ensure that tooling could not contact the foot.1107 shows final cosmetic matching of frame to cylinder diameters

 

[oldengineguy]

1109 shows the exhaust rocker temporarily installed to measure the fitted length of the connecting link between the eccentric strap 1111 and rocker1112. I chose to make the connecting links with left and right hand threads to allow for easy adjustment. 1113 shows the partially finished explosion chambers. These are straight forward mill and drill/tap operations. I chose to mount the chambers to the cylinder with 4-40 studs and nuts rather than the 3-48 bolts called for It looks and feels more substantial. 1115 shows the chambers with 6 3-48 holes for the cover as called out. After a very short initial run the gaskets burnt through at the centre holes which are very close to the inside of the chamber. The fix to this was to drill/tap2 extra holes between the end and centre holes ,closer to the outer edge and assemble with high- temp silicone and no gasket. I don't have pictures of this "repair" ,but have not had any problem with leaks ever since. I used the silicone in place of the gaskets between cyl. and chambers on both intake and exhaust with no leaks 1117 shows CM6 plugs fitted to temporary covers in order to get 'er going .There was still a long way to go from this point but I have had success with these plugs before and knew they would work when time came for start-up. These build notes are "after the fact", the engine has been running since early Oct. but hopefully they are of some use.

 

[karlw144]

Colin, enjoying your pictures and explanations. Sure are a lot of different ways to get the job done. I’ve started my next project; 1/8 scale Meyers Ryder Ericsson. Think I’m in for a challenge!

 

[oldengineguy]

Inlet and exhaust chambers are cast in pairs. I found it easier to separate the inlets but machined the exhaust together until they needed to be cut apart for finishing. Drawings call for 2 piece valves, cast head with pressed in O-1 stem. I chose to make valves from 303 stainless instead .Exhaust chambers call for threaded cast iron "plug" in the top to seal the chamber. I did not have a suitable tap and did not fancy internal single point threading, so made plugs of cold rolled steel to bolt into chamber instead 1134 and 1146 Valve stems are supposed to be drilled through and have pins installed as retainers. I have used "E" clips in machined grooves in these valves and many others with no problems. Seems like an easier way to do the job.

 

[oldengineguy]

Both of the inlet pipes are screwed into the chambers so a method of attaching the mixer block was needed. The block is 2 pieces of brass machined flat & smooth clamped together then drill/reamed to match inlet pipes (5/16). 4 4-40 machine screws clamp the 2 pieces together sealing tightly on "O" rings in grooves on the pipes. The block is drilled/tapped to accept an adapter for the mixer

 

[oldengineguy]

Drawings call for a Buzz coil operated by a complicated brass strip and advance/ retard lever arrangement triggered by 2 screws in the cam gear, or a Hall effect CDI system. I didn't like either option so designed a "distributor" with points and coil/condenser. To drive this distributor I machined the camshaft housing on the flywheel side approx. 1/2 narrower to accept a drive gear. The driven gear has the same number of teeth (60) to give a 1-1 ratio. The dist. housing is bolted to the base under the back of the main frame. A points mounting plate and points from an old Honda along with a shop made 2 lobe cam complete this assembly. Any points and method of mounting would work, I just had these parts available. A 70s era Ski-doo ignition coil and an unknown source condenser mounted inside the base completes the system. Again any suitable coil/condenser would work. 1148 shows the distributor with advance/ retard lever mounted on the base prior to the main frame installation. I drilled locating dowel holes in both parts after fitting and adjusting gear mesh so that future assembly would be easier. A nice fat blue spark to fire propane, works well!

 

[Brian Rupnow]

Very nice work. The engine looks and runs super good. Congratulations.----Brian