I have what I was told is a Quadra 65, but I’ve never heard of that size before. Also if that is what it is would it be too much engine for a scratch built Big Stick wit 100” wing 74” fuselage estimated 30 lb?

Yes, they made a Q65 and it is very similar to their very popular Q75. Post some photos to help ID. I still have (2) Q75 and they were very good engines .... though heavy by modern standards. Also not quite as powerful as similar sized modern engines. They are good dependable engines though and very well made. Some of those Big Sticks tended to be a bit tail heavy so your engine might be a good choice. That engine would give the plane decent sport performance though not blistering performance at 30 Lbs. If your engine mag or electronic ignition?

Thanks for responding it’s a mag, but the site won’t let me upload any pictures for some reason.

If the engine is in good condition, I wouldn't hesitate to use it. Check the mag first as they tend to not work after many years go by and parts are nearly impossible to find these days. Flip the prop with authority to test it. Many of those engines had spring starters. You could change to electronic ignition but at that point you have to ask yourself if a more modern engine is a better way to go. Another part to inspect is the black reed housing .... the part the carb mounts to. These don't usually go bad unless abused but again, nearly impossible to find if bad.

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