Model Woodpecker question

[gbritnell]

Gentlemen,
I getting close to finishing the Woodpecker engine. The drawings call for a small stud to which is attached 2 small springs, one for the pushrod lever and one for the lock out lever. If one builds it as described the pushrod lever will be pulled up against the pushrod and away from the cam. This doesn't mean it wont' work but every engine I have ever built has a spring which holds the pushrod against the cam and the clearance is at the rocker arm end.
There are pictures of a finished engine on several internet sites.
These show a rod of some sort with a spring on it tucked in behind the rocker arm lever. Does anyone have an idea of how this works? The drawings don't spell out anything like this.
My last question is the operation of the 'points'. It call for a button mounted on the governor mechanism. This in turn will rub up against a spring steel lever which is mounted on the pushrod lever. How does one set the time with this contraption?
Thanks for any help,
gbritnell

 

[gbritnell]

Bump
Apparently non of our members have built one of these engines. I guess I'll go with what the drawings call for although I'm not happy with it. I only have a few more parts to make and I can finish this one up. I'll post some pics when finished.
gbritnell

 

[lazylathe]

Hi George,

Catminer has just got his running.
Maybe get in contact and PM him your question!

Andrew

 

[Dave G]

Hi George, if only Lloyd Butler was still with us. Good luck and please let us know what you come up with as I have 2 Woodpecker kits waiting for me. Dave

 

[Catminer]

George;

As Andrew said I have mine running, not bad but still working on bugs. the backwards spring is correct and you will find is a must for the governor to work. Timing is adjusted by the length and shape of the spring arm,I used .015" brass rather than steel. Since this is buzz coil ignition, spark occurs at the time of contact not breaking.The rod and spring is called an adjustment stud and came as an extra drawing along with a picture of installation on a full size engine, see picture. Also came with copies of original sale literature I can post those if it will help.I also drilled out the backside of the governor weights and filled with body lead. Hope this helps, anything else let me know.

Peter
http://i1222.photobucket.com/albums/dd497/catminer/DSCF1417.jpg

http://i1222.photobucket.com/albums/dd497/catminer/DSCF1416.jpg

http://i1222.photobucket.com/albums/dd497/catminer/DSCF1414.jpg

 

[gbritnell]

Thanks ever so much Peter. That explains a lot. I worked on the governor mechanism today and go everything adjusted on the bench. It will need tweaking once it runs. The drawing set that I got didn't include the governor lock mechanism so I appreciate that.
I have some phosphorous bronze sheet in different thicknesses so I used that for the timer arm. I didn't realize it was a buzz coil ignition but now it make sense.
While I have you available, how is your carburetor working? I'm always skeptical about the valve control for the fuel flow as per the Lunkenheimers.
gbritnell

 

[Catminer]

Hi George;

Just came in from the shop, ran Woodpecker for an hour, still not perfect but better.
Carburetor works OK, I did figure out when building it that the plunger on the needle must protrude down into the throat in order to work. I maintained the diameters in the drawings and changed the length to achieve this, seems to like a fair amount of spring tension. The mixture changes a little bit temperature and fuel level of course. I also ended up using a sewing needle rather than what was shown for the fuel needle.
Regards the governor, I have found a couple of old articles in Gas engine magazine that describe the governor on the real engines as problematic, 1/3 scale doesn't improve this. I will try to get the sales pics to you tomorrow.
Also the engine this far likes to run warm at 160+, definitely needs water, but not missing and coasting correctly yet as well as a high compression ratio.

Peter

 

[Catminer]

George;
I also found that the muffler as drawn is quite restrictive, tomorrow I am going to open it up a bit.

Peter

 

[Catminer]

George;

The following is the manufacturers literature and extra drawings that came with the engine.


http://s1222.photobucket.com/albums/dd497/catminer/Woodpecker engine/

 

[gbritnell]

Thanks so much. The factory drawings were a big help. I seem to have the governor working but if it gets too touchy while running I'll try the other spring rod.
George

 

[gbritnell]

I'm bumping this back to the top in hopes that maybe a few more fellows out there will weigh in with some help. Peter and I have been communicating and it seems we have encountered the same problems with this engine.
I have it running. It starts well and runs well but the governor won't work. I have tried different weight springs and even made up the add-on adjusting rod to no avail.
There is one engine running on Youtube and it runs very nicely. I sent the fellow a note but haven't received any reply.
Any help would certainly be appreciated.
gbritnell