Have an Int. 77 rear bath. The dump valves have to be replaced and "HOW DO YOU GET TO THEM ''. Been trying to follow the directions in the manual, but confusing is a mild form of driving me crazy. Has anyone had any experience of getting to them?
It is easier than it looks. Step 1 is to remove the part that goes through the rear bumper by loosening the clamp. Second, loosen the clamp that holds the PVC elbows in place, and remove them. Now you have access to the valves.
Now is the only tough part, and then only if they are glued directly to the tanks. If they are clamped on, loosen the clamps, and remove the valves by turning them 90 degrees, and wiggling them straight out. If they are glued on, you will have to remove the aluminum "floor" in the rear compartment so you can get to them, but it is also not a huge deal.
It is easier than it looks. Step 1 is to remove the part that goes through the rear bumper by loosening the clamp. Second, loosen the clamp that holds the PVC elbows in place, and remove them. Now you have access to the valves.
Now is the only tough part, and then only if they are glued directly to the tanks. If they are clamped on, loosen the clamps, and remove the valves by turning them 90 degrees, and wiggling them straight out. If they are glued on, you will have to remove the aluminum "floor" in the rear compartment so you can get to them, but it is also not a huge deal.
I don't have a part that goes through the rear bumper. It looks impossible to get to the dump valves without dropping the holding tanks pan, or cutting huge holes in the pan to get to the valves. I have removed the bumper and the plastic pan that holds the drainage hose, removed the metal plates where the 3" drain assembly enters the cross members, and have loosened the 3" clamps on the calder coupling.
don't get out the tin snips yet, but when we replaced the valve on our 69 we had to open up that hole in the pan a little, and built a collar out of sheet metal to patch it afterwards. In our case the valve screwed in place, and the 40 year old steel screws were pretty impossible to work with, but after a lot of work and careful vise-grip, grinding etc we got all the pieces out, new valve and gasket in, and stainless screws. Biggest thing is be careful cutting any pipe, some of the fittings are expensive special fittings that aren't made anymore, at least on our year.
I think Overlander is referring to the drain pipe in the rear bumper area, some come through the side of the frame and are connected with a rubber "bandaid" type fitting with clamps (I presume to allow for disassembly and to take up any flex in the system without cracking things).
Trying to follow you guys. Your saying don't get out the tin snips but also saying you did just that and made a hole in the pan? Since I'm replacing both dump valves, I guess I'm cutting 2 holes? This looks like a steel pan the holding tanks are sitting on. Boggles the mind that Airstream didn't see that these things might need replacing and made it so hard to get at.
I'm just saying I don't know your specfic year and model enough to give you sound advice as to the best method since they probably changed in 10 years a little. It did work for us. Case and point, we only have 1 valve, since we don't have a gray tank. General rule of thumb start at the closest point to your sewer hose and carefully take fittings apart where you can, and it should get you decent access to your valve.
Trying to follow you guys. Your saying don't get out the tin snips but also saying you did just that and made a hole in the pan? Since I'm replacing both dump valves, I guess I'm cutting 2 holes? This looks like a steel pan the holding tanks are sitting on. Boggles the mind that Airstream didn't see that these things might need replacing and made it so hard to get at.
Some photos might help us to guide you to the exact method of replacement. Years and models have various configurations and a photo would be of great help in determining what and how to help. They are not that hard to repair/replace - it's the getting at them that slows me down.
BTW - pump some bleach solution through the system to get rid of the "bugs" a little.
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