Author Topic: timing a popcorn engine  (Read 3175 times)

Offline jonesie

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timing a popcorn engine
« on: April 22, 2012, 09:35:44 PM »
i have build stwarts popcorn engine and do not know how to time it.with piston at tdc or all the way away  for the flywheel where is the valve set in the steam chest and where is the eccentric set.build 2 ic engines that are good runners but this is my first air/ steam engine. thanks in advance jonesie

Offline sbwhart

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Re: timing a popcorn engine
« Reply #1 on: April 23, 2012, 01:22:09 AM »
Hi Jonesie

The eccentric is 90 deg infront of to top dead centre.

The first thing you have to do is centralise the slide valve travel:- at top dead centre set the eccentric so the front port is just cracking open, wind it to back dead centre and note where the valve is, screw the valve stem in or out of the square cross bar in the slide valve,to equalise the travel, wind to top dead centre and adjust the eccentric so the port is cracking open again, wind to back dead centre and the adjust the valve stem to centralise, you may have to do this a few times what your'e after is for the port to be just cracking open at Forward and back Dead centres.

Hope this make sence

Stew
A little bit of clearance never got in the road
 :wave:

Location:- Crewe Cheshire

Offline jonesie

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Re: timing a popcorn engine
« Reply #2 on: April 23, 2012, 11:01:33 AM »
thanks  stew i will give that a try,  hope to get it running soon thanks again  jonesie

Offline sbwhart

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Re: timing a popcorn engine
« Reply #3 on: April 23, 2012, 02:01:57 PM »
thanks  stew i will give that a try,  hope to get it running soon thanks again  jonesie

Don't forget the video

 :worthless:


 :D :D :D :D :D :D

Stew
A little bit of clearance never got in the road
 :wave:

Location:- Crewe Cheshire