Wankel Panther brakes

Tonight I reassembled one of the crank seal holders with a new seal and o-ring. I need to check in with the Vintagesled boys and see if I should put some goop on the o-ring, my first instinct is no but its good to check.

Then since it'll be a couple weeks until I get a new clutch I turned my attention to the brakes. The brakes on this sled have really never worked, I'd adjusted them six million different ways to no avail, they either didn't work or they stuck on. I finally ordered new pucks and when I compared the old to the new I found that the stationary puck is pretty much the same but the old moving puck is less than half the thickness of the new one.

I can also see where the brake caliper was rubbing on the rotor from over adjustment.

I had to spend some time cleaning up where the edge of the caliper had been ground into the opening for the puck so the new puck would fit.

With everything installed the brake feels good for the first time ever. It'll be fun to ride this sled with everything working for the first time.

One other note on brakes

I got chastised by the boys around the table of truth over on the Yahoo Group "Vintage-Snowmobiles" for adding DOT 4 brake fluid in my Cobra. Apparently it originally came with DOT5 and as DOT 4 and DOT 5 are not interchangeable or even compatible my using DOT 4 is bad mojo. I'm reasonably sure what came out was DOT 4 as one of the guys says DOT 5 is usually tinted.

Anyway on Saturday I picked up a bottle of DOT 5, they sure don't give that stuff away! I pulled the drain at the caliper and mopped out the master cylinder. Then I refilled with DOT 5 and left the plug out of the caliper until only purple DOT 5 ran out. Its handy that its tinted... With any luck since I only topped up with DOT 4 it won't have had time to hurt anything.

This whole incident makes me wonder if the leaking brake on my TX-L was inadvertently caused by my use of DOT 4...

BRAKES!

Got to spend some time in the garage the other night, one of the problems with the '79 Polaris Cobra is the lack of brakes. The brake caliper on this system has 2 pads, one the caliper pushes against another which stays still in the caliper. Polaris has long used hydraulic brakes and in this case the driven pad is hydraulically actuated and on my sled that pad was stuck.

I found that using a big screwdriver I could pry the pad back away from the disc but when I applied the brake and the pad moved back in it would be stuck against the disc again. I pried and applied and pried and applied and while it seemed like it was getting a little better I wasn't gaining much.

Realistically I knew I needed to pull the caliper and properly clean everything. Unfortunately on this sled the brake caliper is attached to the chaincase inboard of the driven clutch. The driven clutch has to come off for this to happen and the chaincase has to come apart for that. I got as far as opening the chain case and pulling the chain and top sprocket before I gave up. Fortunately with the top sprocket removed the driven clutch can turn since you're not trying to push the track which helped with freeing the pad.

Finally in desperation I carefully squirted a little PB Blaster around the edge of the pad, now when I worked it back and forth I could feel it getting looser and eventually I could apply the brake and it would release easily. With that accomplished I sprayed some brake cleaner on the pad and disc so the PB Blaster wouldn't grease the brakes and everything seems good.

Its a good feeling to make progress.