1968 Fox 36X

Cribbs74 wrote:Hey!

I missed these posts.

Nice example. Pre MK production with BB.

Cool stuff, a real barking dog. Have you run it?

Not run yet. This one identical to 1965 version with inboard ball bearing but no pressure fitting. This also has a venturi insert and circlips retaining the gudgeon pin.

It needs a bit of flushing as it is not seized but gummy inside. Needs to wait for one of my engine cleaning episodes.

It's worth the effort. Stand back when it fires off. Good 60's fun.

I'm going to get another Fox. I really like them for sport flying.

Always fun to run, Typically no so happy with the venturi restrictor in place but it doesn't do a bad job. Gaskets are being reproduced and laser cut available in high quality Fel Pro gasket material . Brian Gardner has just made a run of .36X ABC piston sleeve setups with certain rod modifications and proper deck height. The New Jersey crowd just purchased approx 20 units from Brian and so far the engines seem to be doing well. I will be with legendary Larry Scarinzi next weekend. Larry worked with Duke on these engines. Larry in the 60's would rework these engines and they were known as the "LS tuned" Fox's. Ken

Does this indeed have a rear BB?

Dating a Fox engine is sometimes very difficult to do. All you can do is give a generalization based on CERTAIN characteristics. This engine would fall within the experimental parameters. Duke used needle bearings and ball bearings. It really depends on what is in the engine. Some will say the BB version had better quality control. I disagree with that statement. Duke was cheap period so you received what he offered. The reason for the switch from needles to balls was in regard to the cranks slipping on the needles. This would certainly foul things up. Ken

The standard 36Xs all used rear needle bearings. In 1965, Fox produced a 36X that came in a special box proclaiming "Custom Fitted for Combat". Externally the engine had a lightly polished or tumbled finish and used a rear ball bearing. There was no divider in the exhaust port.

In 1970 the divider was added to the stack, mainly so an exhaust valve could be added. The casting for the front of the engine was also slightly changed. And again in 1970 another "Fitted for Combat" 36X in a different box and again with a rear BB was sold.

These were the only 2 rear BB 36Xs.