The

"McVickerish" Engine

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19 May 2010:

Well, with some mods to the valve train, I now have it running on air.

   

       Lengthened rocker.                        Boring valve cylinder.                  Parts ready for assembly.

After checking the dimensions on the original patent, I found that I'd designed myself into a hole.  The McVicker rocker arm has a ratio of about 1.7:1.  I cut and welded a piece into the rocker and the longest I could make it and still have the pushrod at any semblance of a decent angle only gave about 1.3:1 so I had to make up the difference in the valve actuator cylinder diameter.

 

I am limited in how big I could bore out the valve actuator cylinder without having to find a bigger hunk of steel somewhere and go to all the work to whittle a new one.  What I did was "go for broke".  I simply put the cylinder up in the mill and bored her out as far as I could.  To help myself in the pushrod angle department, I tilted the cylinder in the mill so the bore tips up toward the front of the engine.

 

I then made a new piston out of acetyl copolymer, a Delrin or Nylon-like plastic.  It is good up to 200 degrees and has less creep than Delrin so it should work.  Time will tell.

 

                     Running On Air.                                               Detail of Valve Cylinder & Rocker.

After putting it back together, I hooked up the air and gave it a shot.  Success!  If the crankshaft is located as in the picture above left, it will start right off with about 60PSI of air.  If the crankshaft is at about half stroke, it will rock back and forth until it gets up enough speed to get all the way around.  In the half-stroke mode, it will eventually start to run in whichever direction it thinks best.

 

I've uploaded a video to YouTube.  You can see it here:

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20 May 2010:

Not much was done today.  I did get the new piston made for the valve actuator cylinder.  It has a 9/16" x 0.4" deep relief in the head.  

Old check valve spring on left.  New spring on right

I also put a stiffer spring on the check valve and did a re-lap.  The engine now motors on air with about 30PSI and I think that's good enough until I begin fuel tests.

 

I also reworked one of my Alpha DeLaval oilers with a check valve and mounted it on the engine.

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21 May 2010:

I've got the ignition sensing transistor and magnet mounted and am starting on the fuel tank.

Ignition sensing transistor and magnet.

It's kind of hard to see the magnet but it is to the left of the sensor tab.  I spot milled a slight depression in the flywheel and glued the magnet in it.  The cable is made that will plug-in to the ignition module.

 

Now on to the fuel tank.  After looking around the shop for suitable materials and finding that my supply of 0.031" copper sheet has dwindled, I decided to use a piece of a hunk of 8" diameter (1/4" wall) brass pipe I got on my last "scrapping" expedition.

  The raw material.                                   The cut piece.                              Squaring up the ends.

I managed to cut off a 3" long piece of this by holding it to the bandsaw and rotating it as it was cut.  Then, I mounted it in the 4-jaw chuck of my lathe and trued-up the ends.

 

Romoving the biggest boogers.     Laid up for cutting the top (bottom).

The pipe was really grungy with some old paint, dings, scratches and other uglies so, after I got the ends squared, I used some sandpaper to remove the biggest uglies, then followed the sandpaper with Scotchbrite and steel wool, finishing with heavy duty brass polish.  It ain't gonna be the slickest hunka brass around but it won't be shabby either.

 

The top and bottom will be some of the remainder of the copper sheet.  I'm cutting it about 1/4" bigger in diameter than the pipe and will tack solder then hammer the copper around the edges  before finish soldering.  There will be a 1" deep well in the center of the bottom (made from 1" copper pipe and a cap) which will have a drain and the fuel line will also be about halfway down in the well so the tank can nearly completely empty before fuel feed is interrupted.

 

The filler cap is one that I've unsweated from a Gunk can and will sweat in the top sheet of the tank.  All in all, it shouldn't be too awfully shabby.

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22 May 2010:

Well, I'm running out of stuff to do before the "Moment of Truth".  Now, the gas tank is about done.

Fuel well, strainer and pickup.

I made the fuel well out of some scrap 5/8" copper tubing, a 1/4NPT ferrule adapter and some bits and pieces of copper line.  The 5/8" tubing is soldered into the center of the tank and the fitting is soldered into the 5/8" tubing.  The strainer, soldered to the end of the 1/8" tubing is from some fine bronze screen I've had for a long time.  The line to the engine will be 1/8" copper.

Tacking the bottom plate.                        Hammering the edge.                        Bottom flowed in place.

The bottom and top plates were wire brushed, fluxed and tinned before laying together and tacking with my little jeweler's soldering iron.  The top and bottom had been cut a little oversize so, after tacking into place, they could be hammered down around the edges before using the propane torch to fill and flow the solder.

 

The fill cap was sweated off of the Gunk can, cleaned and tinned again and sweated to the top plate of the tank.

Semi-finished tank.

After polishing on the metals and clear coating them, all I have to do is to make the mounting brackets.  That's tomorrow's project.

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23 May 2010:

TODAY The McVickerish Engine MADE SMOKE FOR THE FIRST TIME!

This photo was taken right after the first smoke was made.

To tell the truth, it didn't continue to run because for some reason I'll have to think out, once the governor kicked in, it wouldn't fire again when it slowed down although the plug was firing.

 

It also made a lot of black smoke and subsequent attempts to keep it running seem to indicate a mixer problem.

I'm going to take a couple of days off from the project to catch up on some other stuff and think on it.

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27 May 2010:

Today, I did some work on the mixer.  I made a crude choke so I could increase the suction then I hooked up my variable speed motor and spun it.  After some adjustments, I got it to get up on the governor and back to hitting a few times.  It was starting to heat up so I quit that and worked on a cooling tank.  Maybe tomorrow, I can get the colling tank done and hooked up.  That will let me run it longer.

 

One thing I find is that it probably could do with a larger flywheel.  If I can get to an old engine flea market, maybe I can find a flywheel about 20 inches in diameter.  That should give me enough inertia to hold the speed a bit more constant.

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28 May 2010:

The cooling tank is finished and leaking.

Engine on test stand with motor and cooling tank.

The tank is made out of a piece of microwave waveguide I had sitting around.  I don't know why I keep that State Fair aluminum solder around!  Yesterday, I tried yet again to get it to work when attaching the bottom to the tank and, although it would start to flow and look like it had wetted right, the tank is leaky.  I'll slap some thick oil based paint around the joint on the inside.  That oughta stop it.

 

I think I'm getting a little closer to the engine running right.  It ran for about two minutes after changing the exhaust and intake valve springs around some.  Then, the valve actuator piston started sticking and holding the exhaust valve open.

 

When it was running, it ran at about 800 RPM, a little fast for me but it would hit once and then miss, I guess, about ten licks.  Even with the motor belted up and turned off, it held speed very well so I think it's going to make plenty of power for "The 2009 Algore Edition Green Hybrid Hoyt Clagwell."  I'm planning on taking the Hvid/gas engine off of it, converting it back to Hvid and skidding it for display. 

 

When I took the actuator off and took it apart, it was pretty full of oil so I think I'll increase the size of the bleed hole and pipe it up to the exhaust.  When the engine is running, a pretty good amount of oil blows out of it.  I have the oiler set to about 8 drops a minute so nothing binds up.  After I've gotten it running right and broken-in, I can adjust the oiler down some, and it may stop being so sloppy.

 

I'm interested in weaning it off the motor so I can unbelt it and see how slowly it will run.

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29 May 2010:

I resized the valve actuator piston so it doesn't bind in the cylinder and the engine runs better.

Valve actuator bleed pipe added.

I also increased the size of the bleeder hole in the valve actuator cylinder.  It was originally 0.040" diameter and the cylinder was loading-up with oil so I redrilled it to 0.060".  To keep the mess down, I also made the cover for the bleed hole and have a piece of 1/8" copper tubing going between there and the exhaust elbow so at least all the crud will be going out the exhaust.

First sustained run.

Although there are still a few bugs to work out, the engine ran for about 15 minutes today.  I will be modifying the mixer by making a reducer for the venturi.  I also plan to make a metallic valve actuator piston because the copolymer piston binds in the cylinder when the engine warms up.

 

The engine smokes a lot from the back of the piston.  This is not blowby but is the oily smoke from the valve actuator release port that is uncovered at the top of the exhaust stroke.  The smoke will likely be less after the engine has been run-in and I can turn down the oiler.-

 

Oh, yes.  The exhaust is VERY loud, more like a rifle shot.  I believe this is because the exhaust valve opens very quickly.  If you didn't know it, you'd think it was a slow running 2-cycle like a Fairmont. 

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30 May 2010:

The danged cooling tank still leaks!  I may have to take it off and get serious about leak stopping.  Either that or use some more of the air conditioning condenser coil and make another radiator.

 

Anyhoo - today, the engine ran for about an hour (off and on).  To try to solve the valve actuator piston problem and not having any brass big enough, I turned a new piston out of 6061-T1 aluminum.  The bore is just over 1.1" so I made the piston to what I thought would be a sloppy fit with a clearance of about 0.002".  After about an hour, it started sticking and finally seized to a point where the engine wouldn't run.  I'll take it apart again tomorrow and see how bad the piston is galled.  If it's not too bad and the bore is still good, I'll turn about another 0.002" off the diameter and try it again.

 

After getting it tweaked to where it ran pretty good, I sat around and watched it.  I've come to the conclusion that McVicker was the inspiration for Maytag "motors".  Smoky, stinky and irritatingly loud!  If I'm gonna use it on the 2009 Hoyt-Clagwell, I'll have to come up with a good muffler or I'll get outlawed at shows.

 

Oh, by the way, I put an optical tach to the connecting rod and found that the engine seems happy at about 1500 RPM.  I did get it slowed down to around 700 RPM but the testing period came to an end (stuck valve piston) and I didn't really get to tweak it for that speed.  

 

The mixer still needs to be diddled and that's for later.

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31 May 2010:

Since I plan to put the McVickerish Engine on the 2009 Hoyt-Clagwell and really don't like how it sounds sans muffler, I've made up a new exhaust system for the tractor.

  

          The raw materials.                                            The finished muffler and tailpipe.

The muffler housing is a 12" piece of leftover frame tubing for the 2009 Hoyt-Clagwell.  I took the former exhaust pipe off the tractor and cut it as shown in the left photo.

 

Ends were made for the muffler from the 1/8" sheet and the holes for the approximately 1.25" O.D. pipe were flycut.  The "holes", or pieces left after cutting the openings from the ends, were then welded onto the inside ends of the exhaust pipes to plug them.  The inlet and outlet pipes were welded to the ends leaving about 1/4" between them.

 

20 1/4" diameter holes were drilled into the inlet pipe, pointing down.  The aggregate area of the 20 holes is slightly more than the I.D. of the pipe.  The outlet pipe has 19 of the 1/4" holes drilled in it, pointing up.  I figure that, since the exhaust will be cooling in the muffler, it shouldn't need quite as much space to get out as it did to get in ....... Science!!??

 

The ends were welded on and a lot of die grinding was done to make my awful looking welds look decent and a coat of barbeque paint was slapped-on to cover the rest of the mess.  The mounting bracket will be used to bolt the exhaust assembly to the frame of the 2009 Hoyt-Clagwell with the tailpipe exiting at the rear.

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6 June 2010:

In the last few days, I've removed the Hvid/Gas engine from the 2009 Algore Edition Green Hybrid Hoyt-Clagwell and have mounted the McVickerish engine.  The cooling has been plumbed and the alternator has been remounted to the other side.

 

I've also redesigned the ignition so it will have a rev-limiter.  This took longer than anticipated because I spent the better part of a day chasing an instability gremlin.  I finally found it and the ignition's ready with a potentiometer to adjust the speed of the engine.

 

I've also made a modification to the mixer.

   

Choking plate modification for mixer.

Since the engine would only run with the crude choke almost all the way on, I modified the mixer by cutting a piece of 0.031" steel and soldering a short length of 3/8" copper tubing to it.  The tubing was then filed to a shape that partially wraps around the jet.  We'll see how this works.

 

I'm also working on a starting crank.  Since the engine will run either direction, I've designed the crank so the handle can be moved from one side to the other and have made two engagement ramps.  If the handle is shifted one way, the clockwise ramp engages the gib key and if the handle is shifted the other way, the counterclockwise ramp on the other side engages the key.

 

I should be ready to run it again tomorrow.

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7 June 2010:

I finished the crank today.  

(The handle appears to be bent but that's just the "fisheye" effect of the camera lens.)

   

Crank ready for welding.           Counterclockwise configuration*.              Clockwise configuration*.    

(*: Please note that the configuration reverses for all of our friends in New Zealand, Oz, South Africa, and other places south of the equator.)

 

The handle of the crank will slide in the outer end.  The part that goes over the crankshaft and engages the key is faced opposite on opposite sides so, by sliding the handle from one end to the other, the engine can be cranked in either direction.

 

After getting the crank finished, I trotted the outfit outside and just about wore out the crank.  At first, the valve actuator piston started to stick so I turned the piston to increase the clearance to about 0.005", a sloppy fit.  At least it doesn't stick now.

 

Then, I wrestled with the fuel mixture.  I could get the engine to run for a few seconds but it would sorry out and I discovered I could save it by poking on the intake valve to let it breathe.  There is a sweet spot in the needle adjustment but it seems to be a moving target.  

 

Once I get the engine dialed in so it runs nice and sit back to let it run, it gets sorry and quits.  After this, it takes some doing to get it to run again.  To get it to start, I have to richen up the fuel mixture, thus losing the previous setting and I have to go through the same procedure to find the sweet spot.

 

I decided to quit for the day because, sitting in the 90+ degree heat, I'd created a small sweat lake beneath the drywall bucket I was sitting on.  The good thing is that I lost a couple of pounds from sweat.  The bad thing is that I'll gain it all back at dinner this evening .......  Grrrrrr!

 

The McVickerish powered 2009 Algore Edition Green Hybrid Hoyt-Clagwell.

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10 June 2010:

In the last few days, a crankshaft guard (anti-oil-slinger device) was made and the mixer was again modified.  

 

This time, I shortened the air horn so it stops before encircling the jet.  I also tapered the end of the jet so it comes more to a point.  Finally, I reworked the taper on the needle valve so it isn't so critical to adjustment.

 

Again, I backed it out of the shop and cranked.  After a while it decided to run.  In defense of the engine, I'll admit that I couldn't stop fiddling with it and just let it run.  After fiddling until it quit, I'd have to crank it quite a bit to get it to fire off.  I believe I've got a bad spark plug because after washing the soot off of it with solvent and blowing it dry, the engine would finally start.  What I should do is to break-down, get a 14mm spark plug tap and rework the head to get rid of the 10mm plug that I think is too small and soots-up and fouls too easily.

 

Before heat stroke set-in, I quit for the day.  More thinking and fiddling and I may have it ready to take for a run through the neighborhood.

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16 June 2010:

After a few days of fiddling with it, I decided that the mixer needed to be remade.  

 

Basic parts.                                                                                    Choke parts.

My theory is that the first mixer didn't have enough internal volume and was, maybe, too sophisticated for the early design engine.  This mixer looks like a mixer from a period engine.  It is made from some 1/2"NPT pipe fittings and stuff mined from the 'ol junk box.

 

                  All the parts.                                                                                     Assembled mixer.

The whole mixer is made without any drawn plan and I'm not sure how well it will work.  The choke cap rotates to open and close the air inlet slot.  I drilled a #50 hole in the bottom of the choke cap to let any accumulated gasoline run out.

 

The jet is made from a 3/8-24 bolt I had and the needle is the one from the former mixer.  I didn't realize until I'd started on it that the bolt is stainless, which made it a bit tricky to machine.  In any case, the jet is a #60 drilled hole.  Tomorrow, I'll work on a check valve then it's on to testing if it's not too hot outside.

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17 June 2010:

I made the check valve and put the new mixer on the engine.  After FINALLY getting it started and tweaked-in, it ran all right and was up on the governor (firing every time spark reappeared when slowing).  I tried loading it until it fired every time but, before it got to that point, it would peter-out.  I'm not sure what the cause is but, since carburetion changes are affecting the running, I'll place that as the most likely suspect.

 

All-in-all, the longest time it ran was for about a half hour and quit unexpectedly when I was in the driveway talking to a neighbor who was interested and had come over to see what I was doing.  Since I was done tuckered-out from the heat and cranking, I just pushed it back in and quit for the day.  I hope all that happened was that it ran out of gas.

 

Oh, yes.  I got the data plate stamped and mounted on the engine.  Serial Number 003.

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24 June 2010:

I did a little more on it today and think I've made a breakthrough ....... although I'm not really sure I know what it is.

    

Valve actuator with second oil blow hole.                                                             Rubber "seal" for pushrod.        

Since the engine ran for quite a while the last time I tested it and quit mysteriously, I decided the problem wasn't anything serious so I went about making it run neater.  This was accomplished by drilling another "oil blow" hole at the pushrod end of the cylinder and then made a small aluminum manifold to catch the crud and blow it to the exhaust pipe.  The pushrod seal was made using a piece of rubberized fabric with about a 3/16" hole in it through which the 1/4" pushrod fits.  So far, so good - no oily splatter all over the fuel tank, control panel and me.

 

After putting it back together, I worked for a while getting it started.  I think there's a method to start these things.  If  the engine doesn't fire hard the first time, it won't fully exhaust the cylinder so the next time the engine cycles, it doesn't get a good charge because of the spent charge remaining in the cylinder and fails to fire.  Continuing to crank has no result because of a bad charge and no exhaust valve operation to clear the cylinder for a fresh charge.  What I think works is to pull it through with the air inlet covered to get a good charge in it.  Pull it over compression smartly and, if it fires hard and tries to quit, put a little opening pressure on the intake valve.  Apparently, that helps clear the cylinder so it can get a decent charge in the cylinder until it's up to speed.

 

Now, if it fails to continue to run, you have to hold the intake valve open and rotate the crank several times to clear the cylinder.  Then, I choke it through one intake stroke and crank it over the next.  This method seems to work most of the time but still needs refinement..


First extended running and drive.

After I got it started and got the mixture tweaked-in, it ran nicely, up on the governor and firing every time the plug fired.  Feeling lucky, I took The 2009 Algore Edition Green Hybrid Hoyt-Clagwell for a ride.  When warmed up, the charge rate of the alternator could be adjusted until the engine fired every time and it ran pretty well, able to move the tractor in high gear on the level and charge the battery at the same time.  On grades, the alternator output current had to be limited a bit so the engine wouldn't bog down but this was to be expected and the battery supplied the extra juice.

 

All in all today, I ran the engine over an hour.  The temperature at the outlet of the water jacket got up to 180 and I had to open the circulation valve a bit to keep it from rising over that.  After thinking about it for a while, I think I really should turn up the circulation so the temperature stays around 140.  This is because the head doesn't have any water passages and if oil is dripped on it, it will smoke immediately, a little too hot for my comfort.

 

Anyway, the McVickerish Engine is close to being ready for prime time.  I will post another movie of it soon.

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25 June 2010:

Today, I did a test.  I started the engine and let it run (at about 750 RPM) under light load until the outlet water temperature was 160 degrees.  At that point, I measured the cylinder head temperature with the thermocouple stuck in beside the spark plug connector.

          

      Water outlet temperature.                                             Cylinder head temperature.

As you can see, the head is getting pretty hot.  It actually peaked at near 320 degrees but, to get a stable reading I had to stop the engine because the ignition was causing the reading to be jittery and the temperature had dropped a little before I had gotten the camera out.

 

To my way of thinking, this is entirely too hot.  What I think will help keep the temperature down a is to replace the 1/32" (0.031") composition head gasket with a 0.020" solid copper gasket as in The Homebrew Hvid.  The composition gasket surely has some heat insulating properties so, changing to the heat conducting copper gasket should help.

 

While I have it apart, I'll give a hard look at the possibility of drilling one or more water passages in the head, although space will really be tight.

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26 June 2010:

After pulling the head and looking it over, I decided to make some water cavities in the head and forego the solid copper gasket.  I also think that the engine doesn't need any higher compression because even now, it doesn't act like it wants to run slow..


The head got so hot, it bonded to the gasket.

I had to give the head a couple of belts with a mallet to get the gasket broken loose from the jug.  When I got the head on the bench, I had to use a knife to scrape the gasket off!  It had gotten so hot that the binder in the asbestos composition material glued it firmly to the head surface.

       

Drilling and milling out the cavities.

After careful consideration, I figured that there was ample metal to remove to allow for some water cavities.  I can't call them passages because I can't connect them within the head and water circulation from the jacket will be via thermal currents.


Cooling water cavities.

It was kind of tedious but I now have a "ventilated" head.  After I got the head off, I noticed that there is some lost motion in the wrist pin so, when I have the jug off for drilling the connecting passages, I'll check it out.  The pin was on the "snug" side but I thought that it would break-in.  I may have been mistaken.  We'll see.

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27 June 2010:

Well, I took the jug off preparatory to drilling the connecting passages to the head and checked the wrist pin.  It's limber but not loose so I'm going to leave it alone.


Drilled connecting water passages to the head.

It ain't real purdy but it'll do.  You can see where the holes partially intersect the 1/2" thick cylinder liner.   This time, I greased the jug and head before putting the head back on.  Maybe the gasket won't stick.

 

It's all back together and the cooling system is filled but won't have time to test run it today or tomorrow.  Maybe Tuesday or Wednesday.  My guess is that the water outlet temperature will go up faster but the head will be somewhat cooler - hopefully under 200 degrees or so.

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30 June 2010:

Today, I fired up the engine again to see how the extra cooling to the head works.  

     

Water and head temperature with improved head cooling.

One thing I noticed was that the water temperature rises more quickly and it takes more circulation to keep it down to 160.  Also, the head temperature is now below 230 degrees so the extra cooling is working, moving heat from the head to the water jacket.  I don't think boiling will be a problem because at 170 degrees water temperature (the highest I allowed it to get today), I see no steam bubbles in the radiator, leading me to believe the combination of circulation and a bit of added antifreeze is working.

 

Now, all I've got to do is figure out why it wimps-out and quits occasionally.  Sometimes, it takes a lot of cranking to get it going again.  It could be that the exhaust valve doesn't open sometimes and the spent charge contaminates what little new charge gets past the inlet valve.  I found that if I hold the intake valve open for a turn or two before it stops completely, it will sometimes begin to run again.  I can see how that could have been a problem to plague the McVicker engines in their day.

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8 August 2010:

Over the past month or so, I've been tweaking the engine some.  In the last couple of days, I've had a sort of breakthrough.  The cause for the wimping-out when the temperature is at the operating point was that the aluminum piston in the valve actuation cylinder was galling just enough to make the exhaust valve hang slightly open.

 

A couple of days ago, I made a new piston out of copolymer plastic (a little like Teflon).  The first try was with a clearance to the cylinder of about 0.005".  When the engine got up to about 140 degrees, the piston began sticking again.  I removed it and removed another 0.005" from the piston.  It then ran until I stopped it.

 

There are still some tweaks to do.  It is hard to start when cold and I've got to figure that one out.  Once running, though, it is fine.  If I slowly increase the load by increasing the current output of the alternator, the engine latches on the governor less and less until, when the load is just right, it runs constantly.  The load has to be tweaked a little to keep the engine running because, when it is constantly "off the latch" it is putting out full power.  Any slight increase in load causes it to fall on it's face.

 

I think that, with a little more work, I will be able to show The 2009-1/2 Algore Edition Green Hybrid Hoyt-Clagwell without too much embarrassment.   A few more tweaks and I'll post a movie of it in it's final(?) configuration.

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18 August 2010:

Over the past couple of weeks, I've been fiddling with the engine and have it running a little better.  It continues to occasionally wimp-out and quit when hot.  I've added a couple of thousandths of width to the ring groove of the valve piston, not to much effect.

 

I also modified the check valve in the valve actuator so the valve stem is guided better.  I also made the spring compression adjustable.  This maybe made a little difference.

 

The wrist (gudgeon) pin was starting to get a bit on the noisy side so I pulled the jug and removed the rod from the crank.  The bushing and the pin had a galled spot on them from either being fitted too tight or lack of lubrication or simply being run too fast for the amount of lube it could get.  I ordered a caged needle bearing and used a new dowel pin and put it back together.  It is a bit quieter now.

 

Now, I'm experimenting with intake valve strength and have about got this point of adjustment refined.  The engine still will run fine for up to an hour or so, then just wimp-out and quit.  Then, it's a real bugger to re-start.  There could still be an issue with the valve actuation cylinder and temperature.  I'm afraid that, if I give the piston any more clearance (it is already at about 0.010" (0.254mm), it may become so loose as to not allow the ring to seal or cock and bind in the cylinder.

 

I know I promised another movie but it has to behave better first.

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24 August 2010:

Well, after tweaking the valve actuator, valve spring tensions, mixer, etc. the engine is still hard to start and quits regularly for no good reason.  I believe it quits because occasionally, it doesn't fire hard enough to fully open the exhaust valve.  That leads to contamination of the next charge and an even weaker combustion that then causes the engine to stop.

 

I now believe I know why Mr. McVicker's engine wasn't a commercial success and I most likely won't be able to make the design work reliably.  I have therefore decided to study other means of operating the exhaust valve in order to keep the engine gearless and camless as was the original intent of the project.  Now, having said that, I know that the design will be complicated somewhat over a geared or gearless cam driven exhaust valve.

 

I'll go into this in the next page, 

The McVickerish Engine, Page Four

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Oh, yes - I AM having  fun!

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