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PDWA switch rebuilding help

ichthos

Darth Vader
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Got my PDWA switch out and it was filled with crud. I bought a repair kit ahead of time from Moss so I wouldn't have down time. The repair kit I have has o-rings like Paul shows in his rebuild article. Mine looks like the pic below. I noticed that Moss also sells a repair kit for ones with lip type seals is that what I have? Thanks for your help, Kevin
 

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Kevin, the lip style must be what you have. I have heard of these, but never have seen one or the pistons to see the difference. When you get yours apart, it would be nice to see some pictures of the lip seals and the different kit and it's part number.
 
I didn't realize there were three different types of pistons for the TR6. The one Moss kit takes care of two, and I am hoping the other kit takes care of mine. I don't want to take the seals off the piston until I am sure I have the correct repair kit. I will post some pics once I the other kit. By the way, if there is fluid leaking from the top of the white switch, doesn't this mean the seals are bad, or is crud in there enough to cause it? It is not so bad that fluid is flowing out the top, but it is definitely wet where the wire plugs in.
Kevin
 
There should be no fluid in the space between the two seals.
 
047.jpg


This is the central shaft from my Spitfire's PDWA. How different does yours look? (i can't see it well in the picture). The main thing I remember being different was the early generation ones had squared off edges to the "o-ring" while the later ones are round.

What is of primay import is simply keeping fluid from reaching the center of the unit.

Jody
 
Well, the piston looks to be different than mine on the ends, so swapping to the other seals doesn't seem to be an option. Hmmmmm.......
 
The other Moss kit states that "Kit for lip type seals includes a new piston for o-ring seals and o-rings," so I am guessing they are just upgrading the piston to the one you have, Paul, since the lip seals are actually no longer being made. A 69 seems to always be full of surprises. By the way, I just got the motor you sent, Paul. Thanks again, Kevin
 
And I got your check yesterday. Thank you!!

It looks like you need the new kit. Well, you can work on your heater while you wait for the kit. Don't forget to check the air blowing out. It should be wired properly, but check to be sure before you put the case back in the car.
 
The Buckeye Triumph archives have/had good articles on replacing the seals and even a drawing on how to machine your own new piston to work with o-ring seals.

The PDWA piston shown in Jody's picture is the type I have found easiest to work on. Cleaning them up is pretty easy and fitting new seals is a snap. The one on our '72 Spit was very different. It had odd bore sizes and the piston was actually in two pieces.

As a footnote to replacing the seals, I have found that the electrical switch itself can be reconditioned. If you look at the knurled plastic base of the switch connector you will find a little circular spot filled with a whitish material. If you carefully drill out that material you will be able to unscrew the plastic connector from the switch and expose its contacts. A little work with some ScotchBrite and/or steel wool and the moving and fixed switch (brass) parts will be ready for use again. Apply a little dielectric grease to the contact surfaces, then screw the plastic part back onto the metal. A little pipe dope in the spot you drilled will secure the switch parts again. Of course, I have seen the references to other switches that can be used on the PDWA should you not wish to re-use the switch you have.
 
Doug, that makes sense on the switch. I may be oversimplifying things, but it looks like all the switch is is two electrodes encased in plastic. Poolboy mentioned that there should be no fluid between the seals. Mine did have fluid (and crud) there which is why I think my switch has a small amount of corrosion. I will just try cleaning my old one up first. Thanks for getting the motor to me so quick Paul. The top of my motor stuck out of a hole at the top of the box slightly - the new one does not. A much better design. I just had to cover the old hole with two SS fender washers. I am waiting on wheel box covers from another forum member and some bits from TRF and Moss, so it looks like it will be a while before I am driving again. Things should go quickly once they do get here. I am off to see my new grand daughter in Ohio on Monday. Hopefully my parts will be here when I get home.
Kevin
 
their is a switch you can get at the chevy place that replace the switch and you only use one of the peg but cant find the number off hand, its just a grounding switch

Hondo
 
Ford used the switch as well: Ford PDWA Switch C8AZ-2B264-A
 
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