How To: C15a Wire-3 restoration

[rob love]

I remember those days of turning things on the drill press. Once I finally picked up and installed the lathe a whole new world opened.

When I got the job at the Shilo museum, I would bring stuff home to turn. Then one day I sliced my thumb open pretty good...it happens, but if it's company material, then it should be done on company time and company machinery. So I scoured the DND catalogue of material for suitable lathes, checked DRMIS for available ones, and got a very very nice Afghanistan veteran: a 7-1/2 HP Colchester with digital readout that only served over there for less than a year, was shipped back and was languishing in the Montreal supply depot. I now have a favorite lathe.

[Jordan Baker]

I can’t wait to get a metal lathe. It’s on my list but so is a new deck and some landscaping around the house.

Anyway back to fun stuff out in the shop. Today I just wanted to get a few small things installed on the engine. I was fortunate that the wartime engine still had the original drain cock and steam bypass fitting. After cleaning them up I decided to use them. However the mounting holes were smaller on the new engine. Thankfully brass adapter fittings are available. I screwed in the drain fitting only to have it snap off inside the block. I didn’t have any of the extractor bits so I simply drilled it it carefully then ran a threading tap. Another trip to town was now in order and I picked up another fitting. This time I made sure to not put that one last turn into it. All worked out.

[Jordan Baker]

Finally started in on reassembling the transmission. I’m going with the Royal Purple 75/90 gear oil Rob suggested. I dipped the bearings into some of the oil before inserting them. I also dipped the the one gear set with the bushings before pressing the shaft into place.

[Jordan Baker]

The transmission is almost fully reassembled. All of the gears and bearings are back in and no parts are left over. One question I do have is about wiring the screws on the input shaft retainer. Can I use any wire that will snugly fit the holes in the screws or is there a special locking wire I should be using? Also is there a certain way I should wire them up? The manual isn’t very clear on this?

[Grant Bowker]

On aircraft there are often 2 wires used, twisted together between bolts and arranged so that the bolts could tighten without breaking the wire but not loosen. In your application, you could probably get away with one wire in almost any configuration and it would be hard for the bolts to loosen even a quarter turn before being stopped by the wire.

[Jordan Baker]

I also managed to get the NOS shifter forks installed in the top this afternoon. All went smoothly even without the special tool for depressing the little ball as the shaft goes in. I used a flat screwdriver and it worked really well. It did take a while until I managed to get the three forks in the correct position. The manual doesn’t really say much on this step. With that I did some trial fitting of it on the main case and all lined up. Next up is cleaning up my stick shifters.

[Phil Waterman]

Hi Jordan

Someplace I have a pair of photos of the transmission and the forks in the neutral possition to make life easier when reassembling transmission keep a copy of it in my manual in the shop. Will try and find and post.

To install the detent balls I just took a short lenght of wooden dowel with a notch in the end to hold the ball in the fork while pushing the shaft in. The little dowel is tagged and lives in my odd tool drawer along with all those other tools you need for working on CMPs.

On my transmissions on the front flange there are little metal links, two bolts to link, with tabs to keep the cab bolts from working loose. Once found a box of them at a flea market, on the rear seal plate the edge of the is bent to lock the bolts. When using pressed in seals with out the plate I just used Locktight. Though I guess failing the seal and plate type, one could just cut a flat plate out of light steel and drill it for the holes so that you bend the endge up to capture the bolts.

Really enjoying your progess reports, keeps my mind fresh on working on CMPs during those times when none of my trucks need work.

Cheers Phil