Vertical I.C. Rupnow Engine

Home Model Engine Machinist Forum

Help Support Home Model Engine Machinist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Mark, I know how it happens. Sometimes life just gets in your way, doesn't it. Hope you are feeling okay now.---Brian
 
Hi Brian. I got the new points but now having problems with the flywheel. I used socket head cap screws instead of grub screws on the original set up. These screws eventually worked loose and smashed against the screw that held the points in place. On trying to undo the flywheel screws then snapped off so now I'm trying to drill them out and replace them with grub screws.
 
Herbie---I had issues with the original flywheel myself, having it come lose. If you look in my build thread you will see that I ended up putting a steel band around the hub to give a bit more material for the grub screws to anchor in. See post #153-- If you can get the flywheel off, you might have better luck cleaning out the bore and drilling /tapping new holes.---Brian
 
New holes is the way to go. Impossible to drill out the old screws. At least the flywheel is off
 
Brian - Life has gotten in the way as well as some mill issues

Herbie - My plan is to use the Starting hub to compress a tapered mount for the flywheel. This should hopefully do away with any issues of things coming loose.

I can't see me getting much done before the end of MArch unfortunately. Maybe a few little things. I suppose they all add up.

Cheers

Bruce
 
I was searching for a carburetor to use with the Hoglet and found on the Hoglet tread a reference to this carb.
Duly down loaded.

I like to thank Brian for kindly sharing his designs and supply very professional drawings.
 
Well I finally got everything back together but still not running. I used to get the occasional puff of smoke out the exhaust but even that's not happening. Tried shortening the intake spring until it got too short. I've now made a new spring and will try again. I have renewed respect for pioneers like Henry Ford with his " kitchen sink engine". He didn't have the luxury of logging on to HMEM to seek advice. :D
 
I feel for you Herbie, it's taken me ages to get engines running in the past. I assume you've still got compression? If so, you can put your finger over the end of the carb to force it to take a 'shot' of fuel even if your intake spring is too strong. If it won't fire that shot of fuel then it's not the spring causing the primary issue. So check valve and ignition timing, if they're both good then it can only be a carb issue.

With mine, I altered the cam a little, reducing it's duration. My exhaust valve opens a whisker before BDC and closes right on TDC. I'm not suggesting you alter your cam but just letting you know it runs fine on these settings. I have ignition timing set a couple of degrees before TDC but it runs fine bang on TDC as well.

When I first got mine running I didn't have any gaskets in the carb. After a while I made and fitted PTFE gaskets hoping I'd get throttle response and easier tuning but I couldn't get it to run again (although it was firing consistently) and I had to muck with the carb settings a lot, til I eventually had the best setting. I probably had more trouble getting it to run after fitting the gaskets than I did the very first time.

Keep at it, you'll get there!
 
Herbie--I feel your pain. If you have fuel, and spark, and compression, then you almost have to get some puffs of smoke or pops or bangs. I don't know what other advice I can give you. So much comes down to having compression, perhaps more than any other factor.---Brian
 
Hi , I am close to finishing this engine, could someone help me out with what "o ring" size I need to order for the piston.
Thanks Matt
 
The o-ring is a 1/16" cross section Viton o-ring, with an outer diameter equal to the outer diameter of the piston.
 

Latest posts

Back
Top