Very well done indeed Dave, I never had any doubts about it at all. th_wav :bow:
Just a note about the engine, don't forget to give it a drink of oil otherwise it will soon wear itself away.
The late Bob Shores swore by the use of 5% WD40 addition to his fuel to keep his engines in fine condition, the first couple of tankfuls he gave it 10%, just to help with the running in.
Feels good, doesn't it!!! Congratulations, and welcome to the world of people who have built their own internal combustion engine from scratch.---Brian
The late Bob Shores swore by the use of 5% WD40 addition to his fuel to keep his engines in fine condition, the first couple of tankfuls he gave it 10%, just to help with the running in.
Does oil in the fuel work with a vapor carb? I'm guessing that it does, as the gas I'm using is mixed with oil (for my two-stroke lawnmower), the level is going down in the jar, and it's not just oil at the bottom of the jar. But I'm not sure...
I still need to fix the leaky intake valve - I'm getting a puff out the mixture valve's intake every time it fires.
I've probably started it up 20 times this afternoon (a couple times with a flick of the wrist instead of the drill)!
It needs to be leaned out as it warms up, and squeezing the intake tube seems to act as a throttle pretty well. Can't wait to make a new tank with real adjustments.
OK, I've made a simple control gizmo to go on top if the vapor carb. It allows adjustment of both the air/vapor mix, and the overall volume of vapor/air mix allowed to the engine:
It certainly helps, but I'm not satisfied with it yet. This afternoon I'm going to experiment with different fuel/oil mixes - the stuff I'm using is to ancient Lawn Boy specs of 8 oz oil per gallon, which is a LOT of oil...
I want to make a fixture of some sort to hold the vapor tank in place on the base plate, and also make a wood base for it that will accommodate the coil & battery.
I need to replace the main bearings too - they were kinda sloppy to begin with and all this testing has not improved them. Maybe ball bearings...
I think straight Coleman fuel with no oil is the ticket. The gasoline/oil mix WAS getting more oily as the fuel was drawn off, and this resulted in no running while there was still a good bit of "stuff" left in the tank. So if I did that it would mean I'd have to dump the tank from time to time to get rid of the left over oil, which sounds like a mess. With straight Coleman fuel it runs just as well almost empty as half full, which will be better.
I've been taking notes, and now have a reliable cold start routine, and can also adjust the mixture as it warms up and keep it running for several minutes. It then over heats and dies. I think a cooling fan is in order, and I've located a couple of 2 1/2" 12v ones in doorstop computers sitting around here ;D
Since there is no oil in the fuel I'm going to have to do the cylinder oiler per the plans. So this coming week I'll tear it down to do that, plus bearings, oiler, fan, base, etc., and maybe some "pretty". :
I'm thoroughly hooked - thinking a hit & miss next...
More likely Dave that your engine is dieing from no lube rather than overheating. Your going to find that with no oil the piston will get sticky in the bore, stall and gall. WD40 or equivalent mixed with the Coleman doesn't have a residue issue. May wanna try this blend to evalueate before a mechanical oiler. Dave
Dave, I've been liberally oiling and squirting WD40 in the end of the cylinder when running on straight gas - it's not seizing up. I think I need to revisit the leaky intake valve and/or screw around with the mixture controls. I'll be happy if I can get it to run five minutes at a time reliably...
Replacing the main bearings may help too - they were quite sloppy, which could conceivably make the ignition timing & dwell float around somewhat. I've got some sealed ball bearings I'm going to put in.
Progress! Bored out the side plates for sealed bearings, and cleaned up and (slightly) polished things. Wood base is glued up and will be ready for sanding & finishing tomorrow. ;D
I've been piddling around with the vapor fuel tank / carburetor on my plumbing parts engine for months. Sometimes it runs great and other times it's very temperamental. I've been using WD40 mixed with Coleman fuel and that lubricates things nicely without any residue in the tank.
My problem seems to be one of the fuel mixture being too lean. I know I'm sucking some air in through the intake valve stem, but despite 3 different attempts at remaking the valve and the valve guide, I can't seem to get it right. I can tell I have this problem because when I squirt a little oil on the intake valve stem with the engine running, it starts smoking out the exhaust. My engine also seems to be really sensitive to the level of fuel in the fuel tank.