The only markings on it is Fox on the side. The cylinder top is slightly larger diameter than my Fox 35. I am thinking either a 36 or 40.
Bill,
If "29" is not stamped on top of bypass side mounting lug, it is a .36. Since the area between the top 2 fins is not filled it is probably a 1972 model.
From the factory the 29 venturi was fitted with a very thin restrictor . The counterweight on the crankshaft of the .29 is stamped with "29". I'm looking at a .29 and .36 side by side and the distance between the top of the cylinder casting and the head is a little more on the 36. The bore and stroke are not listed in the Model Engine encyclopedia but I would venture a guess the .29 and .36 share the same bore. I think the 36 is a stroked 29. If I get time this weekend I will see if the heads are interchangeable
The shaft runs in a bushed bearing and the cylinder liner is of the conventional drop in type. The piston is meehanite and a solid wrist pin is retained by snap rings.
I had one of these new in 72 and used it for slow combat and sport flying 'til I got my ST G21 .35s. I used it on my "beater" planes for a while and it performed well. It ran a nice solid wet 2 stroke and never burnt up after a lean run, probably due to a lot more metal then the 35.
One hot day I thought it was a goner when I buried the nose straight into the asphalt so far that when I pulled it out, the ends of the yellow taipan prop looked just like a crocus plant coming up in the spring. Later after fileing the bur off the front of the shaft and cleaning it out, I tried it on the test stand and it ran great. I put it on one of my beater planes and it ran so well and so fast that they accused me of hopping it up and didn't want to let me run it in any ad hoc races. I told the guys that all I did was dynamically tune it from 60 feet up with a sudden stop.
I turned out that one day I looked at it and noticed the liner was rotated abou 25 to 30 degrees clockwise out of position. I put it back to the regular position and it ran OK. I always meant to try turning back to the 25 to 30 degrees of but never did. When I got back into the hobby a couple of years ago I could no longer find that engine. Its on my to do list on one of the ones I have now.
edited starting here:
I just used photshop to brighten and enlarge the picture and am pretty sure its a .36 I don't see 29 on the bypass side lug and it dosn't look as if it has a restrictor in the venturi.
Topic: What Fox engine is this (Read 814 times)
