Questions Regarding Jerry Howell Powerhouse 4 Cycle Build

[ErikBolyard]

Hello everyone,

I’m in the early stages of working on a 4 cycle “Powerhouse” engine by Jerry HowelI, and I had a few questions for the experts here.

1. What type of stainless steel would be best for making the exhaust valves?

2. Does anyone have any recommendations for making custom springs? I have no experience with this, and I’m unsure how best to go about it.

3. The crankshaft gear meshes with a brass gear on the camshaft. Would it be best to make the crankshaft gear out of steel, or Dura-Bar cast iron?


Thank you in advance for the advice.

 

[oldengineguy]

Erik : FWIW I made the valves from 303 stainless, it machines well. Never had any luck making good springs, have used hardware store assortments with success, but lots of folks wind their own. I made both gears from brass , don't think wear is a factor on small engines A fun engine to build.
Colin

 

[rklopp]

1. What type of stainless steel would be best for making the exhaust valves?

2. Does anyone have any recommendations for making custom springs? I have no experience with this, and I’m unsure how best to go about it.

3. The crankshaft gear meshes with a brass gear on the camshaft. Would it be best to make the crankshaft gear out of steel, or Dura-Bar cast iron?

1. 17-4 condition A or 303 are fine. 17-4 Condition A machines almost as easily as 303 and nowhere near as difficult as 304 or 316. You can heat treat the 17-4 at 900 F to harden without distortion after machining and polishing.
2. Go to this link: https://s3-us-west-1.amazonaws.com/hmt-forum/how_to_make_springs.pdf
3. Either steel or cast iron would be fine. Assuming the gears are kept lubed, brass, bronze, iron, steel, or maybe even acetal plastic could work. Pick something easy to machine.