Gas Cap Rebuild 1980 XS 400

[Beepybeep]

Hello Hello!

This is my first time posting to this wonderfully helpful forum and luckily, today's issue is pretty easy and tame.

I am replacing some components of my gas cap and have run into a bit of a snag looking for parts. I ordered a new rubber gasket from Mikes XS (cheap!) which should be a breeze to swap. However, on the opposite side of the metal plate that the gasket attaches to, there is a little breather hole. Once upon a time it was covered with foam with a brass washer over it, but the foam has disintegrated and nothing is holding the brass washer on.

Does anyone know where I can get replacement foam and how to fasten it to the cap? Or does someone know what this competent is called so I can just replace it outright?

Thanks for the help!

BP

 

[RazeOrion]

Looks like that specific parts you're looking for aren't sold individually (at least by yamahapartshouse.com).

You best bet is going to be buying a re-pro gas cap to keep it simple
Fuel Cap Replica - mikesxs.com

 

[avemachina]

I did something similar to RazeOrion's solution with my own damaged gas cap--I bought a reproduction/aftermarket gascap, took out the key cylinder from my old one, and put it into the new body to keep the key matching. If you want to go that route, it's only two screws holding the key cylinder in, but make sure to orient the latch spring correctly so that the "default position" of the latch is closed and it doesn't flop around. It's easy to test it out on the tank to make sure it's correct before you tighten everything down.

I think the foam-and-brass serves as a vent--in case fuel pressure becomes excessive, like on a hot day where gas might evaporate. You could cheese it with a fuel-resistant foam and a fuel-resistant adhesive applied sparingly (especially around the brass pinhole), but it seems like the path of least resistance is to just do a body transplant.

 

[RazeOrion]

I did something similar to RazeOrion's solution with my own damaged gas cap--I bought a reproduction/aftermarket gascap, took out the key cylinder from my old one, and put it into the new body to keep the key matching.

It's only three screws (I believe) holding the mechanism in, but make sure you've got the right-size Phillips head screwdriver so you don't strip them. There's a little spring for the latch, so just make sure that's positioned in a way that lets it lock onto the lip of the fuel tank when you push down.

That's pretty smart. Keeping the cylinfder to keep the same set of keys.

Wish I could do that, haha. The guy I'm buying my XS400 from already has 2 different keys for it