PDWA; tips for getting the shuttle out of it.

[Scott_Hower]

Car is a late Spitfire.

Trying to replace the seals in my PDWA. I have it out and mostly apart. I've rebuilt a bunch of these in the past and normally it's just a matter of blocking the ports and blowing the shuttle out of the bore with some compressed air.

This one is different. I tried the compressed air trick and the shuttle wouldnt move more than about 3/8 of an inch. The shuttle is a three piece thing: a piston with a pair of what look like bushings on either end of it. A pair of e-clips hold them in position. I have the clips removed and the piston out, but the bushings are stuck inside the bore and won't budge. The front seal is also out, but I can't get at the back one. Any ideas for getting them out of the bore?

Tried letting it soak in PBBlaster for a few days. Tried compressed air; tried using a brass drift to move the front one. No go. I guess the next step is heat?

If I have to replace it, it looks like the late Spitfire uses metric threads? Anyone confirm that?

 

[hondo402000]

maybe hook it back up to the brake lines and hydrolicly force it out

hondo

 

[JodyFKerr]

Here's an exploded view of the PDWA from my mum's Spitfire ('78). Does it look the same as yours? The shuttle here came out easily, but there was enough clearance to get some small padded pliers on to the end of it if need be. (I use scraps of leather to pad my pliers when I don't want to mar a surface).

To get the final internal bits out I bent a little piece of wire into a hook shape.

Jody

 

[Scott_Hower]

Yep, exact same thing.

The two bushings on the shuttle are still stuck in the bore. If heat doesn't work, prob going to need to find a used one.