Spinning Primer Knob

[nippaero]

I have a problem with the knob on my primer spinning. It makes it difficult to lock/unlock the primer. Is there a fix for this? I cant figure out how the knob attaches unless it is pressed on.

[ghostflyer]

I had a similar problem and the knob is threaded on and I used super glue to hold it on But after a about 18 months the knob cracked and fell apart. I tried buying one , nobody could supply a knob so a washer was soldered onto the shalf with a nut and the whole built up with heat shrink to protect against sharp edges. Works just great. I could have bought a completely new unit from Spruce for Mega bucks.

[Bruce Fenstermacher]

Our original knob is long gone. Replacement knob is glued on with JB weld.

I'd use "Super Glue" (cyanoacrylate). You can find this at hobby shops in a thicker viscosity that cures in about 60 seconds which might fill the gaps and give you the time you need to properly place/thread the knob back on. A 5 minute epoxy would also work.

[nippaero]

Maybe my threads are striped then. My know just turns in place. I can't pull it off.

[Bruce Fenstermacher]

If you can't pull it off then I'd use this "super glue" Let it wick between the knob and the shaft.

[nippaero]

I'll give that a try. I have some CA.

[GAHorn]

Drill and "pin" it with a roll-pin.

[Bruce Fenstermacher]

I would not drill and pin it. First you are likely to get an oversize hole in the knob as the plastic way melt. Second I think it likely the 70 year old plastic knob will likely split at the drilled holes.

[GAHorn]

I would not drill and pin it. First you are likely to get an oversize hole in the knob as the plastic way melt. Second I think it likely the 70 year old plastic knob will likely split at the drilled holes.

I agree. My advice is not appropriate for a plastic knob. I had not recalled it was a plastic knob, I had to go back and look at the pic.

[nippaero]

Just to close the loop on this. I ended up putting a couple drops of thin CA on it and letting it wick into the knob. SO far it has ben working great. No more loose knob.