Does anyone know how to remove an end cap from the rear cross beam?. It appears that the cast iron has rusted on to the aluminium cross beam. I am trying to remove the traveller car to replace the plastic wheels, so far I have removed the rivets and banged on the end cap with a hammer and screwdriver, but it wont budge.

I don't think the end caps are iron, they should be cast aluminum. I recall that there was a rivet or screw on the bottom of the crossbar as well, so you might be missing that one. once you have made sure you have all the rivets completely drilled out, you just have to tap the end cap off with a flat head screw driver. If it has corroded and you can't get it off, you may have to break it off and get another.

THanks, I didnt check underneath.

I just replaced a traveler car on my P18. Just drilled out the rivets, switched cars and put the cap back on. Pic is the 'before' image.

I've had to do the same thing you are attempting and agree with Dan. While you're back there you should check/replace the rivets holding the triangular piece of aluminum that supports the swivelling traveller cam cleats to the rear crossbar. Mine went on me while sailing last summer and it wasn't a lot of fun getting back to the beach. At least I wasn't in a race.

I just filed the end cap to match the contour of the traveller track extrusion. With the bolt removed, the traveller car can come off.
I have at least one cap, because I cracked a beam... hmm front beam... never mind.

I checked again and there's no rivet underneath (the crossbar bottom is flush with the outside portion of the hull). I think that the best solution is Dan's (filing the end cap top to match the traveller rail).

Thanks for the help.