Broke a small stud on fuel pump :(

aschwerin · Jul 8, 2017

So I did a really stupid thing and I need somebody more clever than I to fix it.

Its a CAV diesel pump on a 1971 Ford 2000. I seem to have over-torqued the closed nut that keeps the top cover on, and after a couple months time/hours use, it snapped. Diesel spurting everywhere. In the picture you can see the washer/seal to the left, then the broken stud, and the nut on its side to the right. In front is the other nut that holds the cover on.

So I need to seal that hole, keep the cover reliably torqued down, and preferably be able to remove cover in the future without a grinder/torch. Ideas please?

Thanks ahead.

CalG · Jul 8, 2017

so drill the bugger out with a Left Hand twist drill bit about 2/3 the diameter of the cap screw.

If drilling it doesn't get it to reverse, there is your hole for an easy out.

No rocket science envolved, but you do need to purchase the left hand twist drill bit.

Advice: prick punch a stating location and predrill with a conventional 1/8th inch diameter drill bit prior to using the left cutting bit.
Double check your prick punch and center punch location CAREFULLY! Holes can be moved if caught early!

Spanner · Jul 8, 2017

Stud will be easy to remove/replace with the cover removed.

Clean area thoroughly before commencing work (Wash with suitable solvent) and lay a clean cloth on ground in cased you drop any parts.

Fit new sealing washers and o-rings to all locations.

Get a Parts picture before commencing disassembly.

:wrench:

DJ54 · Jul 8, 2017

That one doesn't look nearly as bad as the one that snapped on my Roosa Master pump. The shoulder of the screw was actually rusted, and swelled in the cap. I had to drill it out so thin, and worked the cap to break it off. Broke off, just above the boss of the top of the pump. Actually backed it out with my fingers.

The bad thing is, when I went to the diesel shop to get OEM replacement screws, all they have anymore, are the "tamper proof" type screws, at about $2.50 ea. The ones in mine were a #10 screw size thread. I went to the local Fastenal, and got hex socket type screws to replace them. A pack of 10 was like $5.00, but better than $2.50 ea., plus having to buy a special socket to install them. They are only torqued to 10 in. lbs.

DLTTrekkers · Jul 9, 2017

Prosese as Spanner stated !

thepumpguysc · Jul 9, 2017

The cover has to come off to replace the stud.. its held in place w/ a bend over tab inside.. they are REAL cheap..
NO OTHER WAY to seal it up.. Just watch some utube videos on the procedure.. EASY.. just google CAV top cover leak..
Get a new cover gasket, change the 4 orings on the shafts while your in there.. a stud & 2 new fiber washers for the acorn nuts & a new nut & done.. total cost is less than 20.00

aschwerin · Jul 9, 2017

Thanks guys, I hadn't considered the stud would be removable. I'll have a look.

Changing the seals is how I got here

My life would have been easier just letting the the old seals leak...at least now I know the trick about seating the throttle shaft...that gave me hours of grief this spring... I think pumpguy helped me with that...