The Rotary Valve Engine III
Now is the time that I will try to make this into a "Ready For Prime Time" engine.
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3 December 2016:
First things first.  Yesterday, to my surprise, I received both the O rings AND the gear to repair the lathe so today I got back to work.

Replacing the gear, finishing setup of the lathe, etc. went as usual.
The new gear is on the left.
After fixing the lathe, I started on the O ring grooves.
Turning the grooves.                                                         O ring installed and the AWSHOOT showing.                                   After cleaning up the AWSHOOT.
THEN, the AWSHOOT! happened.  When I designed the O ring setup, I didn't even think of the depth of the ports.  The intake seemed to go all right with no evidence of it breaking through but the exhaust just barely broke through and I only found it when I put the O ring in the groove.  I may have to buy another gear and start over on the valve but decided to try to fix it by making an insert and epoxying it in place.  First, I filed the AWSHOOT to get rid of the foil-thin metal.
        The repair insert.                                                              Ready for pressing into place.                                                             Waiting for the epoxy to cure.
The next thing I did was find a piece of thick sheet steel and form it to the shape of the port.  After thoroughly cleaning the port and the repair piece, it was started into the port with the press.  Then it was removed and epoxy applied to both parts.  Finally, the piece was pressed the rest of the way into the port.

Doing this will necessarily reduce the exhaust duration but, if it is necessary I can file a chamfer to the original port edges (except the inner and outer radiuses).  Not filing the radiuses doesn't affect valve timing but will increase the sealing area.  Every little bit helps.

After the epoxy cures, I will have to put the valve back into the lathe to clean up the floor of the groove and the face.

As a note, when I installed the finished intake valve with the O ring, it seemed to have a bit more drag than I thought it should but the dimensions of the groove, squash, etc. are by the book.  We'll see how it works.  I did get five of the ) rings so, if they burn up, I can re-machine the grooves and try again.
4 December 2016:
Well, the fix cured and I got the surfaces machined back to specification on the exhaust valve..
 Increasing I.D. of O Rings.      Finished repair of valve.
I really wasn't happy with the amount of drag on the intake valve seal so I increased the I.D. of the O rings before I put it back together.  The way I did this was to make a mandrel as shown in the photo on the left.  Then, I reversed the O rings onto the mandrel until the inside of the ring was out.  Using my Dremel "toolpost grinder", I took about 0.010" off of it.  This decreased the amount of "squash" from 0.015" to 0.005".  The drag was much less.

After putting it all back together (messed-up one O ring installing the valve in it's bore - tricky), I motored the engine without compression for a few minutes then put the spark plug back in and ran it.  After first starting, it was driving the motor but after a minute or so, it lost some power and the motor took-up the slack.  I ran it like that until the temperature at the top of the cylinder was about 150F then noticed leakage in the form of smoke and oil coming out at the joint between the head and the top plate.

Funny thing is that the leakage was in the area of the intake valve, the one that didn't have to be repaired.  Just to make sure I would get a good indication of what was leaking, I let it run until the temperature was about 215F then shut it down for the day.

Tomorrow, I'll run it again and, if it doesn't do any better, it gets a valvectomy for a post mortem.  There are still a few things I can think of to improve the situation but none of them are easy so I will keep on keepin' on with this until it either runs or proves unworkable.
8 December 2016:
Lately, I've been fiddling with the engine and have made some progress.  After taking the valves out, I found that the O ring on the intake that, like the exhaust O Ring, I had thinned, was showing signs of leakage.  Figuring that it wouldn't do any harm to just take one of the remaining stock O rings and install it on the valve and see if, at the calculated "squash", it would survive.  So far, so good.

The first time I ran it after that, it ran for about five minutes then started knocking.  The knock sounded like a rod knock so I shut it down and slowly turned it over.  I found that the knocking was caused by the top plate hold down nuts unscrewing, causing the valves to be shoved up and down in their bores from the pressure reversals.  As you can see, I made some lock bolts for the hold down nuts and stopped that from happening again.  

Hold down nut locks and an oily mess.
Over the last three days, I've been fiddling and running the engine for short periods.  I find that the locks on the hold down nuts are a big help and the engine is now running on it's own after motoring it started.  When I began the tests with the 2-cycle mix (for valve lubrication), I was running a 16:1 ratio.  You can see in the photo above a little of the oil that puked out of the exhaust.  After running out of the two pints of the 16:1 I'd mixed up, I mixed up some fuel at 24:1.  The engine ran better and didn't seem to be binding-up just like the 16:1.  I'm not sure if it's the change in ratio or the change from reed switch to Hall-Effect sensor for the timer but I now can run more ignition advance.

While running it with the reed switch, there were a couple of instances where the reed stuck closed.  A little tap on the housing cleared that but it occurred a couple of times more so I just changed over to solid-state.

While running the engine today, I did some tests.  Ignition advance looks like it's around 15 degrees BTDC.  The governed RPM is around 570 and at the end of the test run and with the fan running, the temperature at the top of the cylinder was up to 230F.  The exhaust pipe was around 270F.  The length of the run was about a half hour.

Presently, it is cooling off and resting and the stink is airing out of my shop.  It seems that the engine is running better all the time and there is less valve leakage smoke so I can assume the valves aren't leaking as much as they did.

It's getting to the point where I may make a hand crank and see if it can be hand started.  If that works, I'll make a skid for it.
10 December 2016:
After running it yesterday and adjusting the top plate right before shutting it down when it was at around 230F, it cooled off overnight.  This morning the top plate was pretty loose but the engine started right up on the motor.  With the plate loose, it knocked until the engine warmed up a bit but then behaved until I shut the engine down.  I think this means that the O ring seals are working.  

I think it's starting to get to the point where it is more or less reliable for runs of up to about a half hour.  Today, I fueled it with some 30:1 mix and it started right up and ran for about a half hour non-stop except for refilling the gas tank.

A bit of a tweak to the governed speed got it down to a little over 500 RPM and it ran fine until, at the end of the test, the temperature at the top of the cylinder was about 205F with the electric fan running. The temperature hadn't stabilized but I think it heated up more slowly than in earlier tests.  Maybe this is because the piston rings are breaking in.  It could also be because I am able to run the ignition timing more advanced than before due to less leakage in the valves.

I've got a 4 blade 6 inch diameter fan blade ordered and I will belt it to the crankshaft for cooling.  I will also make a choke so I can begin attempting to start it by throwing over the flywheel.
15 December 2016:
Yesterday, I worked on the cooling fan.  I have the fan shaft and bearing mount done.

Fan mount and pulley.
The plan is to use a big O ring as a belt to drive the fan.  The fan is to be mounted to the engine by way of a couple of the crankcase top plate bolts.  I made a bolt out of 1/2" hex bar stock by turning the diameter to that of the recess in the top plate with another, smaller diameter, threaded to 12-24 to screw into the front plate.  The top of the elongated head of the bolt is drilled and tapped for 12-24 machine screws which will attach the fan mount.

Hello, boys and girls.......It's Stuff-Up Time!
    Aw shoot!                                                                              The broken bolt.

As you can see, when tightening the first mounting bolt to the crankcase top plate, the thread bottomed out and, Mister Doofus (That's me) twisted off the bolt in about the hardest place to fix.  There was no way to get the drill into anything close to the right position to drill the bolt for using an Easy Out.  The result was that I had to almost completely disassemble the engine to get the flywheel end plate off.

Once this was done, I put the end plate in the mill and, using the dimensions I had used for the original machining, spotted the broken bolt with a center drill then drilled it out to where one of my Easy Outs was engaged just about at the shank.  I did this to use the strongest part of the Easy Out.  It took some finessing to get the bolt to move without breaking the Easy Out but I got it done.

Now, all I've got to do is put the engine back together, make another bolt and try not to twist another one off.
16 December 2016:
Well, I'm almost back to where I was a couple or three days ago.

The new and improved bolts
Since one of the bolts had broken, I made both of them shorter, duplicates of the ones that are used to mount the fuel tank on the engine.  The flat washers are there because I decided that they needed a wider footprint diameter than the counterbore.  They put all the compression on the top crankcase plate and should be stronger.

Maybe tomorrow, I will get the fan done and can start on the skid.
17 December 2016:
Well, I just got done with the main part of the fan and still need to start on the skid.

And a fine fan it is!
As you can see, I've enlarged the driving pulley.  The fan's rated to 4,500 RPM and my original driving pulley only had it turning around 1,000 RPM.  I now have a ratio of about 3.5:1 which should get the fan up to about 1,750 RPM.  As of now, I'm not sure I will make a guard for the fan because it is partially protected by the flywheel.  Oh, yes - I'm using a big O ring for a belt.
18 December 2016:
I made a fan guard of sorts and have the skid done.

The skid (what else would it be??!!)
The casters are some that a neighbor gave to me.  They are off of some kind of tables and have seen a bit of water.  I cleaned out the ball bearings and repacked them and they will be good enough for this engine.  

While paint dries, I will work on a starting crank.
20 December 2016:
The engine is mounted on the skid (photos later) and I'm working on the starting crank.

Parts for the starting crank.

The means of getting ahold of the crankshaft is a hardened steel pin (out of an old and defunct hard drive) that I turned down.  It engages the keyway and is spring loaded so it will pull out of engagement when the engine starts or so it says here in the fine print.  I still need to drill and tap the button for a setscrew and shape the end of the button.  Then, I will make the arm and handle.  A little welding and it should be done.
21 December 2016:
The crank is finished.

The starting crank.
And a fine crank it is.  The only thing is that it doesn't start the engine.  It's not the crank's fault, I cranked until I got a sore arm and the engine didn't hit a lick.  Tomorrow, I'll re-check the timing and clean the plug and see if it will cooperate.

It IS good exercise, though.
22 December 2016:
Well, I checked everything and found nothing wrong.  Tried hand-cranking it again and didn't get a pop.  Backed-up and went to Plan B.

Here it is on it's skid.
Plan B consisted of making an adapter so I could drive a 5/8" impact socket with the 1/2" drive drillmotor.  The threaded end of the crankshaft was some metric or special size so I simply tapped it for 7/16-14 and screwed-in a short bolt.

It took only about three times over comrpession for it to fire but, try as I might, I couldn't get it to run on it's own.  There appears to be a lot of intake valve leakage so it's going to take a break until after Christmas, maybe into 2017.  I'm now leaning into replacing the bronze valve seats with some 1/8" thick 0-1 steel.  Since the gears are iron, they should get along together.  Also, if the O ring seals continue to be a PITA, I may try cast iron piston rings as seals to see if that makes any difference.

I sort of figured that this design would be a challenge and it's proving to be just that.  I WILL get it to run well, though.

28 December 2016:
I did some fiddling today and decided that the O ring seals were not working as planned.  I removed them and the engine now runs although it still takes the drill motor to get it going.

Running in the driveway.
AND, here's the latest video.  Notice the smoke coming from between the head and the top plate.  That's leakage and there doesn't seem to be any way to get rid of it.
Here's the flick.
It was running about 600 RPM and, after I finished the video, I let it run until it quit on it's own.  At that time, the temperature was up to around 230F at the top of the cylinder.  I will leave everything as it is and see if after a couple run and cool-off cycles, it gets better or worse.
29 December 2016:
Today, I ran the engine for about an hour almost continuously.  Before it would start, I had to tighten the top plate a little to bring up compression.  Once running, I loosened it a little to reduce drag.  After the hour of running, the temperature at the top of the cylinder farthest from the fan was 299 F (148 C) and had just about stabilized.  The engine was running at around 550 RPM.

Valve leakage smoke and note color of exhaust pipe.
As you can see, there was smoke coming from the joint between the head and the top plate.  Tightening the compression nuts didn't minimize the smoke but did load the engine.  I will let it cool off for a few hours and see if it starts any easier and without having to increase the top plate pressure.

It still won't start on the crank.
30 December 2016:
I ran it again today, this time, after tightening the top plate to get it started, I locked it down and let it run until the valves started binding.  This took about 20 minutes at 550 RPM.  When I shut it off, the cylinder head temperature was right at 300F.  I think the faster heating is caused by the valves binding in the head as they expand.

I've been thinking about this and believe that I need to bore and sleecve the valve hub bores for less clearance between the hubs and the bores they run in.  Right now, it's about 0.012" and I think the valves try to cock when compression pushes on them.  If I reduce the clearance to 0.001-0.002", it will keep the valves in place better and may minimize the leakage through the bore and allow me to run the top plate with a little clearance.

There's also the possibility that the bronze seats just cannot withstand the heat.  I could replace the bronze seats with something like 0-1 unhardened tool steel.  It should run against the cast iron valves all right but if anyone out there has a suggestion, I'd be interested in hearing it.

Tomorrow is New Year's Eve so I will be busy rolling out some junque for my selfie.
31 December 2016:
Decided to try running it again today before taking my annual New Year's Eve selfie.  It wouldn't hit a lick until I re-tightened the top plate.  Then, it smoked more than ever and started binding after only a few minutes.  An engineering executive decision was made to remove the head and do the tightening-up of the valves.  I will keep the bronze seats after removing, boring and sleeving the valve bores then reinstalling the seats and re-lapping them.

Valves and seats after about two hours of intermittent running.
Happy New Year!
2 January 2017:
Part of the re-work of the valves is done.  The sleeves were made from a piece of 3"O.D. X 1.5"I.D. steel tube.

Sleeves finished, waiting for boring of head.
The clearance between the valves and the I.D. of the sleeves is about 0.0005".  I think I will use the O rings as an extra seal on the I.D.'s, relying on the O.D. to provide the outside sealing.  I guess I can get away with as little as 0.002" clearance on the outside.  If it tends to bind, I can always take it apart and polish some more clearance on the O.D.'s of the sleeves where they run in the head.

Now comes the confession.  When I designed the valves and head, I forgot to take into consideration any clearance between the gear teeth.  I had everything carefully machined so the pitch diameters intersected, making it impossible to assemble everything.  Rather than sleeve and bore with the correct spacing at that time, I simply bored the valve hub bores until the gears fit.  This made for a lot of clearance and, I'm sure made the leakage worse.  Had I known the valves were so alignment sensitive, I would have fixed the dimensional error earlier.

The photo shows the head with the bronze seats removed.  When boring the diameters in the head, I will take a light cut to remove the epoxy which is stuck pretty good.  
8 January 2017:
After a pause and a few days of just fiddling with it, I've finally gotten the valves to where I think I can re-assemble the engine and give it a test.

Valve sleeves and seats done and ready to assemble.
If I had the head to do over, I think I would have made the valve ports smaller to give more area for sealing and I would have gone ahead and made the bronze seats as big as the sleeve bores, seating the the sleeves on the bronze seats.  This would have made for a sort-of convoluted leakage path and lessened that problem.

Just as I was preparing to bolt the head back on, I wiped out the cylinder bore and found some minor scuffing, probably caused by a little binding in the piston.  If I'd known the engine would run as hot as it does, I would have given the piston a few thousandths more clearance.  As it is, I don't want to unseat the rings so will just shut it down when the temperature gets over about 225F (108C).  I might be able to try to run it again tomorrow.  Before starting it, I will try to hang on to the drill motor and do a compression check to see if there is any improvement.
11 January 2017:
Well....... On the 9th, I put it back together, set the timing and checked the compression.  Remember, it was about 70PSI earlier.  On the 9th, it wouldn't rise over 40PSI!  Big improvement, eh?

I went ahead and motored it with the drill motor and, although it was firing regularly, it wouldn't run off the motor.  After running on the motor until I got tired of holding onto the drill, I quit.  Then, when again checking the valve timing (it was good), I got my right ring finger between the flywheel and the engine base.  OUCH %*#$&&&#*$%&#^#!!!!!

That ended the activities for a few days until the finger was healed enough to quit throbbing (almost there today).  I'll get a new fingernail out of my klutzyness.

I think the problem is that I machined the sleeves to be too close a vertical fit between the head and the gear, which is holding some gap between the valves and seats.  When I tear it down again, I should be able to see wear marks to determine if my theory holds.  If so, I'll face a bit off of the sleeves and put it all back together to see if there's an improvement in compression.

13 January 2017:

I took it apart again this morning and used a sandpaper disc mounted in a tool for the mill to check to see if the valve seats were parallel to the plane of the head.  Surprise!  They were not.

"flattening" the valve seats.
After sanding the seats, I lapped the valves to the seats and, seeing a good pattern, I figured everything would be fine.  Nope!  Compression is still around 45 PSI and it fires but doesn't want to run on it's own.

A good time to think about it for a while longer.
16 January 2017:
Well, here's another nothing report.  I took it apart again and found that there was a problem with the length of the valve (gear) hubs.  Since I'd taken off material from the seats, the valves bottomed on the shoulders at the tops of the valve bores, keeping the valves from seating tightly.

What I did was to turn 0.015" off of the gear tooth portions of the valves, making the hubs longer.  This allowed the valves to press against the seats.  While I had it apart, I lapped the valves and found that they were matching pretty well.

When I got it all back together, I motored it with the drill motor and it sounded like it was running and made a little smoke but wouldn't get off the motor.  I guess you can say that it talked the talk but didn't walk the walk.  The drill motor got hot so I stopped for lunch.  After lunch, I tried again and it acts like it is trying a little harder.  Since it's easy to sit there and spin it with the drill motor, I will just go out and exercise the drill motor a few times to see if it will get good enough to run on it's own.

My thinking now is that I've proven that I can design and build a rotary valve engine that will run.  It never was strong enough to start by hand cranking but I've got the video to prove it would run.  Since I've made the point, I may get another hunk of cast iron and build a poppet valve head.  I will use the sideshaft and one of the valve gears with a face cam attached for the exhaust.  Because of the iffy cooling, I could design a cam stopper arrangement for hit and miss operation.  It has enough displacement so it should run very well with decent valves.

I'm still a-thinkin' on it.
22 January 2017:
Well, I again tried to start the engine but the valves were really leaking today.  Before I scrap the rotary valve head, I'm trying one last thing.  I took it apart again and removed the bronze valve seats.  One thing I found out is that the epoxy blew out between the seats and the head.
The seats removed showing leakage paths.                                               Blanking the new seats.                                                                   Applying the super glue.
As you casn see, there was a lot of leakage.  You can also see where the bronze broke away around the exhaust mounting screws.  I've learned that oillite bronze is not good in this application.  The sintering process when making oillite makes the bronze weak and hard to mount without breakage.

What I did was dig out a piece of 1/8" hot rolled steel to make new seats with.  I think the iron gears will wear reasonably well against the steel as long as I use a 2-cycle oil/gas mix.

I learnesd a trick on the internet for machining thin parts.  After cleaning the sawn out blank, I applied super glue then used the center on the tailstock to press it to the face plate until it hardened.
Holding blank to faceplate while glue sets.                                                     Turning the O.D.                                                                          Facing.                      
After the super glue hardened (a few minutes), I turned the O.D. of the blank and faced it.  The glue held fine and I think it is a really good way to hang on to thin parts.  Even with the interrupted cut, it held.  Just don't get it hot.
Heating seat to loosen super glue.                                                             Seat ibn place.        
To remove the workpiece from the faceplate, simply use a propane torch to heat it.  After the part fell off, I lightly belt sanded the glue from the back.  Before doing the other valve, I will take a very light face cut on the face plate to remove the glue and true it up.  I may try acetone to see if it will melt the glue so I don't have to take material off of the face plate.

Getting the mounting holes, port, etc. in the new seat was easy.  I made some 6-32 transfer punches and, after screwing them into the head and bluing the seat, dropped the seat into it's cavity and tapped it with a hammer handle to transfer the locations to the seat.  After drilling and countersinking the mounting holes, I mounted the seat in the head and, from the opposite side, drilled the head bolt hole.  Then, using a drill bit through the port, I made a series of holes outlining the port in the seat, then, with a carbide burr mounted in the drill press, removed the metal from between the holes and cleaned-up the side walls.

After turning the head back over, I drilled the seat for the head bolt counterbore.

I removed the seat and de-burred it then cleaned the surfaces up with acetone, buttered the space between the seat and the head with epoxy then screwed it down.  After removing the epoxy "squeezins', I stuck the head in the press with about a ton of force to convince the seat to get along with the head.  It will sit there overnight.  Tomorrow, I'll do the intake.

I'm hoping this works because, although I've figured out how to make a face cam actuated poppet valve arrangement, I really don't want to have to buy another hunk of expensive cast iron.
25 January 2017:
A little more progress today.  I finished the intake seat and have it epoxied to the head.  I then used the aluminum sanding tool to flatten both seats and bring them into parallel with the head.

A couple of hours using the Time Saver lapping compound has them looking like they will seal all right.  

Valves lapped and ready to assemble and test.
In a day or two, I will get it together and see what the compression has risen to.  If it's over 60 PSI, the engine should run all right.  For how long, I don't know.
28 January 2017:
After thinking about it for a while, I decided that the exhaust seat was a bit on the iffy side so I spent another hour lapping it until the pattern was good.  I put it all back together, set the clamping force until I could feel some drag on the valves and motored it for a few minutes, checking the compression.  The most I got before I was tired from holding the drill motor and the compression gauge was about 40-45 PSI.  Not very good.

Anyway, I stuck the plug back in, filled the tank with the 32:1 two cycle mix and started motoring it.  At first, it wouldn't fire at all but, when I tightened down the hold down nuts, it started firing.  A little tweaning with the ignition timiing and fuel mixture and it started running off of the motor.  Some more tweaks and and a few re-starts and it ran on it's own.

I let it run, adjusting the hold down pressure until the temperature at the top of the cylinder touched 200F.  I locked the pressure nuts down and decided to let it rest and cool down and see if it would start cold.  I've got the feeling that the valves could be a bit leaky when the engine is cold but we'll see.

After I run it some more, I may tweak the rev limiter on the ignition module to make it hit and miss without stopping the cam to, 1: see if it would run like that and, 2: see if it would run cool enough to stabilize at around 180F.

I really hope this engine will run as a rotary valve engine just to show that this form of rotary valves will actually work after a fashion.
29 January 2017:
This morning, I fired it up again.  I did have to tighten the valve tension for it to have enough compression to start.  I also tried the electronic hit and miss and decided that it didn't do anything to solve the temperature problem so I returned it to the throttle governed option.  Anyway, I like the sound of throttle governed engines better than hit and miss and throttle governed engines take a bit more fiddling and finesse to get them to run well.

While I had it running well, I shut it off and tried to hand crank it.  Although it would occasionally fire, it wouldn't pick up RPM enough to keep running.  The drill motor probably spins it up to about 500 RPM, a point where it will go ahead and run at a slightly faster 550 RPM.

Something else I discovered was that the engine really wants to run faster than the speed I'm comfortable with.  This may be due to the amount of valve overlap it's got as well as the valve leakage.  At the faster speeds, the valves have less time to leak compression away.

........................Time passes...........................

This afternoon, I went back out to the shop and attempted to start the engine just as it was when it was shut down hot.  No luck.  I had to tighten the valves to get it to start and then, after it warmed up a little, I had to loosen them again.

At this point, let's say I'm not going to throw out my perliminary design of a face cam poppet valve setup.
31 January 2017:
This morning, with the engine left as it was after the run of a couple of days earlier and it seemed to have better compression.

A brainstorm occurred yesterday.  Figuring lubrication of the valves was a problem, I resorted to one of the Redneck solutions to all automotive problems ....... STP.  I mixed about 2cc into a tank of gas and, after getting it moved around from motoring, it started running without tightening the valve hold down nuts and pretty soon was running well.  

It was run again today until the temperature approached 220F with no change the valve hold downs so I will let it cool until tomorrow and, after making some cooling shrouds, we'll see if it will again start and run okay.  If I can get the cooling under control, with the engine temperature stabilizing around 200F, it may be worthwhile to continue to develop the rotary valves.

I've come up with some other ideas along that line, including epoxying the sleeves to the cylinder head  That will reduce the cumulative leakage clearance that is handled by the O rings around the valve hubs.
1 February 2017:
I got the cooling fan shrouds done today but don't think I'm quite finished with it  It's made of some scrap pre-painted roofing tin..

Running with the cooling shrouds in place.
The engine appears to run just a little cooler but it still only takes about 15 minutes for the cylinder temperature to reach 250F, which I still think is too hot. I may continue the shroud around the bottom of the fan to more directly move the air over the cylinder and head.

After fiddling with it today, when it runs, the engine just chugs right along until the valves get hot and bog it down.

I ghought a bit more about locking the valve sleeves into the head but that is not a really good possibility due to the trouble of compressing the O rings while inserting the valves in their bores.  There's precious little space and the O ring compressor is hard to remove after getting the O ring started into the sleeve.  About half the time, I have nicked an O ring.

Tomorrow, I will do nothing more than start it and let it run until it gets hot and the valves tighten up amd stop the engine.  I will keep note of the rune time and the temperature of the engine when it stops.

All in all, except for the novelty of the rotary valves, it is a P.I.T.A. to get it started, having to crank it for a while after tightening the valve hold down nuts to get it to start. Then, the hold downs need to be loosened as the engine warms up to keep them from binding.  I guess I've proven a point but it's not what I consider "ready for prime time".
2 February 2017:
Well, today I went out to the shop and checked to see if it had any compression after cooling-off and before tightening the valve tension.  Nothing!

All right, let's pull the cover and have a look at the valves after a couple of hours of running with the steel seats.  Here's what I saw.

Top of the valves.
The first thing I saw was surface rust.  Since this is the first time I've ever seen it on this engine and the humidity has been down lately, I can only blame it on something in the STP.  You can also note the carbon buildup where the stuff has accumulated.  Also not good.  The killer, though is the galling of the exhaust valve face and seat.  Enough is enough!  I'm through wasting time on rotary valves.  I've proven that it will run.  No wonder this idea went nowhere fast.  

I've made the executive decision to abandon the rotary valves and to finish the design of the face cam poppet valve design and modify the engine for a new head..

After I get the head design finished, I will start another page and call it "The Non-Rotary Valve Engine".  Stay tuned.
Boy!  This fun (when things go right)!
Questions or comments?  Email me at [email protected]
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