WoodCutter

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Hello all..
I've got this Fox .25baffel piston,bushing model engine which I bought around 1990. It probably only has about a gallon of fuel ran thru it while mounted on a sport plane. I remember it ran fantastically and never quit in the air ever. I was thinking of mounting it on a sctratch built plane I'm designing now so I took it out of the box to check it's condition.
The main bushing has a bit of slop fore-and-aft mostly but the compression still seems to be pretty good. I ran it on Omega 5% fuel but with no extra castor in it. (I know, I was bad!)
If I remember right, the engine did make a bit of a mess around the nose from the front bushing when I ran it last.

I havn't called Fox yet but assuming they still carry the parts for the engine I was thinking about ordering a main crancase (with bushing inside I'm assuming) and a piston/sleeve/connecting rod set.

My question is this...

Other than backplates and carburetors, I've never really taken apart model engines before. On an older technology engine such as this, is it easy to get it all apart? I would not have to mess around with heating the case to get the sleeve out or any other unusual techniques.

Also would it be easy to put back together without getting the sleeve in "backwards" or anything like that.

I wouldn't mind learning more about glow engines but I don't want to get it all apart and have troubles putting it back together or risk screwing it up.

Thanks in advance for any replies.

Robert

earlwb

It is difficult to say if Fox has parts for the old Fox .25 baffled piston engines or not.
But Fox does have a trade in program where you can trade in your old clunker engine (any brand engine), any condition, and get 50% off the price of a new engine.

But there are quite a few engines and parts that pop up on the auction sites, so you may be able to find the parts to rebuild the engine there too.
One caveat is if the rebuild costs exceeds 50% of the cost for a new engine, then one has to determine if it will be worth it or not.

The Fox .19 and .,25 engines are quite easy to take apart, nothing special needed. You remove the cylinder sleeve and then the piston and then you can slip rod off of the crankpin.

aspeed

If it has fore and aft play, that is normal for a sleeve bearing motor. It likely doesn't need rebuilding at all. A bit of goo coming out the front is a good thing too, for lubrication. (a bit) Just fly it until you are tired of looking at it or it does wierd stuff. If you must take it apart, you can make a mark on the side edge of the cylinder with a corresponding scratch on the top edge of the case to realign it when putting it back together. Also scribe an X or R on the back of the connectiong rod to make sure it goes in the same way. I wouldn't take it apart unless it is really needed as the Foxes say they don't last as long because of the piston wearing differently. Also be careful of the backplate gasket as it will likely be destroyed if it is that old, and may not be available any more. They are not fun to make either.