8N Front Hub Dust Cap Thread

Good Morning. Does anyone have any suggestions to repair the hub threads for the dust cap? I wire wheeled them with my die grinder but there must be some buggered up threads in there. Any help would be appreciated-Jumbo

on the cap itself, or in the hub?

cap is easy.. IF you have a thread file, find the closest side and use it on the section that is damaged. usually a rolled or
flattened thread. However it may simply be easiest to use a triangular file or knife blade file, and just hit the damaged
sections. probably take longer to put the cap in the vice than actually fixing it.

now, if it is instead in the hub, you MIGHT get away with the thread file, otherwise pulling it and using a threading tap.

Thank you. It is the internal thread....any chance you know the diameter and thread pitch?

nope.

if it's the internal thread damaged, just pull the hub.

clean it up in mineral spirits.. diesel.. etc.

then find the damaged spot.

put it int he vice.

grab a BIG tap with close threads and put some gloves on and use that hard tap to work over that softer hub by hand and just go
back and forth maybee with some lite cutting oil or similar light oil. it might take 10 minutes, but unless the threads are
totally roached, you should get it back to letting the cap screw on.

a big pipe plug tap.. or a large bolt tap will likely be best.

If you an start the cap in the threads, I have had luck with valve lapping compound and work it in and out may take a while tho, don't get in a rush. Either that or buy a used one on Ebay.

If you have a set of digital or dial calipers or even a micrometer, you can measure the hub OD for size -it'll be in inches for major diameter of the thread, then scale a 1" length of the thread to get the thread PITCH -most likely a fine thread, like 20 TPI (Threads Per Inch) for example. I don't know why you used a die grinder on threads in the first place, just need to clean out the wheel internally with mineral spirits, ATF, or diesel fuel if replacing bearings and races, then blow out good with compressed air. The trick is to keep dirt and debris out of the grease as that will act only as an attractant and abrasive grinding compound. Buying a tap or thread chaser that size will be very expensive, but maybe your local brake or auto shop has one they could loan you. You can also try taking a swizzle-stick deburring tool and run around the ID of the hub, gently, and to take a file or stone and run softly around the perimeter of the hub to create a sort of chamfer. That may help make the parts mate easier too. ALWAYS start any fastener by hand so as not to cross thread and screw in as far as you can by hand. LESSONS learned, right?

Tim *PloughNman* Daley(MI)