Alpha type stirling engine Problem

Discussion on Stirling or "hot air" engines (all types)
Post Reply
Posts: 3
Joined: Sun Jan 01, 2017 3:41 am

Alpha type stirling engine Problem

Post by imranakhtar » Sun Jan 01, 2017 2:19 pm

Hey i have built an alpha type stirling engine using two honda 70cc cylinders and their pistons. Using the same crankshaft (modified it to have two connecting rods). The problem is that it does not run not matter how much heat i provide it does not spin more than 2-3 rpm by rotating the flywheel by hand while heating and friction b/w pistons is not that much, less than the normal engine because i have done some finishing and leakage is the same as in any motorcycle engine cylinder due to same rings and arrangement. I got the design from a video on youtube ( and tried to build it according to the design and availability of resources. I am using iron chips from lathe machine in regenerator. Here are some of its pictures

Please suggest some improvements and what could go wrong with the engine. :cry:

Ian S C
Posts: 2221
Joined: Thu Dec 02, 2010 5:15 am
Location: New Zealand

Re: Alpha type stirling engine Problem

Post by Ian S C » Mon Jan 02, 2017 2:12 am

There is too much friction in the piston rings used for an internal combustion motor. You could pack the ring grooves with Teflon tape instead.
Cast iron chips are probably too dense. The best regenerators use stainless steel foil, .001" is a good thickness to start with. Stainless mesh, or wire work ok.
Down load (if you havn't all ready) Andy Ross's book "Making Stirling Engines" (it's free, about 65 pages), that goes into regenerators.
Ian S
PS is the crankcase sealed, if so, and you are running at atmospheric pressure, it needs to be vented to atmosphere, or you will get back pressure. It only needs sealing if the motor is pressurised.

Post Reply