Can this AFM be fixed?

[robhaynes]

Watch this video and you will see my AFM issue.

http://www.haynesfam.org/20160910_122512.mp4

Basically there is a loud squeaking noise when I push the AFM flap. I would think the bearings are worn allowing too much play causing the flap to scrape. Is there a way to fix this or is it buy-a-rebuilt-one time?

[RRoller123]

Mine did the same thing. Many of us lightly sand the aluminum housing in the area of the flap interference, with ~200 grit sandpaper, until it moves freely when held in the upright orientation, then clean thoroughly. It takes a while, but that is good, as you can work up to it slowly if the interference is not too bad.

You can just see the scrape marks on mine where the flap was dragging on the housing. (And the obvious PO backfire residue as well, all cleaned up now.)

[So Cal Mark]

be careful of sanding too much, gaps around the flap will cause air to bypass the flap rendering the AFM useless

[RRoller123]

+1, just enough to stop it from dragging. Use a very light sandpaper, maybe even 400 and work very slowly.

[Ramzi]

+2

But also determine the cause. Very often the door becomes bent after a backfire. Make certain there are no other issues which might cause further damage.

[robhaynes]

Thanks, the sanding worked and I took to heart the cautions about sanding too much. I would think though, that a little more air passing over the AFM flap could easily be adjusted out.

[RRoller123]

you could richen the mixture by playing with the spring wheel, but we generally don't want to go there.....

[So Cal Mark]

don't change the spring pressure in the afm!