Half Scale Ford Quadricycle Engine

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How tough would it be to hog a one piece crankshaft. I know they are a pain but you just cant beat them for strength.

Wow Steve...I never thought of making the Crankshaft one solid piece. I'm not sure I can do that. I suppose if I start with a rough rectangular piece the width and length of the Crank arms and mill out the center portion...then put in a 4-jaw or turn between centers? Wow...that would be a challenge for me but I guess not impossible.

I ended up drilling and tapping through everything and stuffed a bolt with Loc-tite to keep them together....so far so good.

I ended up re-cutting the valve that was not holding compression, made a new longer valve guide bushing...we'll see later today. I did have it running on one cylinder but not well.
 
Wow Steve...I never thought of making the Crankshaft one solid piece. I'm not sure I can do that. I suppose if I start with a rough rectangular piece the width and length of the Crank arms and mill out the center portion...then put in a 4-jaw or turn between centers? Wow...that would be a challenge for me but I guess not impossible.


Not knowing what your crankshaft looks like It's impossible for me to know if it can be done. Just thought I would throw it out there. I have not had good luck with multi piece crankshafts.
 
Well it is running on a fuel drip, but for about 5 to 10 seconds and then stops. Longest run has been tonight with still almost no compression in one cylinder. I tried vapor fuel and it did not work.
 
Ahhhhhhhhhhhh!

I found last night that one of my intake valves was not working! I took the spark plug out of the cylinder I know has compression so I could focus on the cylinder that does not work.

I noticed on the return stroke it was not sucking my thumb in the intake as the other side. I switched the intake valve with the one I know works and it held compression! The problem was the length of the intake valve spring! The damn spring was 1/8" longer which was not allowing it to open enough to suck in fuel. I snipped it off and now I have good compression in both cylinders!!!

I ran it for about 10 seconds, it sucked it too much fuel, and flooded.

Damn it.
 
I'm going to try to keep it like the original but I've heard a lot of good things about the vapor carbs...I'll keep messing with it. I don't want to post a video until it is running better. Thanks for your patience!
 
Glad to hear you discovered your problem ,looking forward to seeing it running.
Vince
 
Ahh, sweet success. Feels good when it finally works, huh.

I'm not too impressed with vapor carbs. I've experimented around with them a lot and found them to have some problems. Throttling them is difficult and they are very sensitive to ambient temperature as well as fuel level in the tank. Also, if you have any air leaks in your intake system, around valve stems/guides, etc., it's very difficult to get the mixture rich enough. Some people might have better luck, but I've converted all my engines back to standard carburetors.

Chuck
 
That is good to know Chuck. It was actually your pimento jar vapor fuel tank that gave me the idea. I have been trying to copy your vapor fuel tank design for a few weeks now. I'll keep trying it but for this engine a fuel drip regular carb may be best.
 
Forgot to mention that my new valves and seats were never lapped. They held compression perfectly right away. It did take about 6 valves and 4 manifolds to finally get it right...but I'm finally getting the hang of it!

The engine runs on a fuel soaked paper towel but not directly from a fuel drip...just like in a previous post. I'll post a video of it running tomorrow and hopefully someone can "hear" the sound it makes and maybe know if it needs more air/fuel?
 
https://youtu.be/ZdF9W_HAsIE

I think that I finally have it!

Just for kicks I hooked it up to an oiler filled with Coleman fuel and it started running and would not stop!

Some fussing with the carb, timing, and cooling should give me a good runner!
 
Now that it is running I decided to remove the connecting rods and run an end mill along the outer face. I painted the interior of the groove the same color as the flywheel. The flywheel already has plenty of battle scars but I'll leave them alone for now. The carb can still be improved but mu shop needs some much needed attention.

Here are some pictures.

Now maybe I can focus on the full scale Quadricycle!

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Thanks Steve...sometimes you and everyone else gives me the motivation to stick with it and not lose my temper.

I'm looking forward to bringing it to the next show!
 
Hello Chris, Congratulations on your achievement, perseverance wins out. Are you looking at building the full scale engine or the complete vehicle. I am in South East Australia where we are getting cold days and nights, currently building a heater for my workshop to continue my projects. Good luck for the new venture. Norm
 
Hello Chris, Congratulations on your achievement, perseverance wins out. Are you looking at building the full scale engine or the complete vehicle. I am in South East Australia where we are getting cold days and nights, currently building a heater for my workshop to continue my projects. Good luck for the new venture. Norm

Thank you Norm!

I am currently building the entire vehicle...or trying to! I have a build somewhere on HMEM...stay warm down under! It's almost summer for us.
 
So I've been fussing with the cooling system for this engine and it has been quite frustrating. I'm trying to do what Henry Ford did about 120 years ago and it is not easy! I first had the tubing connected wrong and all the coolant spilled out and over the engine...that was a lot of fun. I finally have it right now but I have a small leak around one of the water jackets.

Also, I can't get the engine to run! I started messing with the vapor fuel tank and fittings and it won't stay running.

I tried a couple of things that all failed but one time I hooked up the hose wrong and all the gas was sucked into the engine! I had to take the manifolds off and drain the gas. Now the pistons are "sticky"...probably the gas eating away the O-rings that I was supposed to replace with Viton!

I'll keep at it but this weekend has been one failure after another. :wall:
 
Of course shortly after my rant I worked on the carb and noticed the main contact was bent. It is a thin piece of copper that after repeated hits from the flywheel bolt it is starting to break off. I will have to replace this was a piece of spring stock. Anyway, I adjusted the copper contact to fire about 15-degrees before TDC, adjusted my new carb, and off it went!

The engine ran for about 5 minutes with the new cooling system.

Videos and pictures to come.
 
Of course shortly after my rant I worked on the carb and noticed the main contact was bent. It is a thin piece of copper that after repeated hits from the flywheel bolt it is starting to break off. I will have to replace this was a piece of spring stock. Anyway, I adjusted the copper contact to fire about 15-degrees before TDC, adjusted my new carb, and off it went!

The engine ran for about 5 minutes with the new cooling system.

Videos and pictures to come.

Chris, that's great news. Really look forward to seeing it running like it should.

BTW, I still can't believe that o-rings actually work for more than a minute or two in an IC engine. Goes against all my instincts, I must admit.

Your efforts prove that perseverance and problem solving is everything when it come to engine development. Well done!

Regards, RossG
radial1951
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