I think one of the reed valves has gone in my Brat. It was really hard to start when cold, and I took a look, and there was a couple big peices of melted plastic blocking the choke open. I removed those, and she seems to be running fine now - back to normal I would say, so I don't think the plastic hurt anything other than keeping the choke from closing. It looks like the plastic was already hard by the time it reached to carb. Anyway - what should I do? I could replace the AIS valve - should I do both at the same time, or just the bad one? Or maybe should I just remove them completely? I like the idea of removing them, but will I still pass emmisions? And how difficult is it to block off their passages if I should decide to give em the boot? Also - if I remove them, I know it will affect the ability of the cat to work correctly, but by how much? If I remove them should I remove the cat too because it really isn't doing anything without the AIS system.... or will it still function to a degree?

 

GD

We had a big discussion about that valve in the past. I hope it's still in the archives. You can buy a replacement valve with the newer style body for about $17; open it up, take out the reed valve portion and put it in the old body. Also, check the local pull a part yard to replace the plastic pieces. You need to replace that also since now you're pumping exhaust gasses into the underhood area; it's not nice stuff to be breathing while you're driving. Give me a call and I'll try to get the part number of the valve for you.

 

Rick, here's the link:

http://usmb.ultimatesubaru.org/forum/showthread.php?s=&threadid=2569&highlight=air+suction+valve

Yeah - I have been driving with the windows down - it does indeed smell pretty nasty in there. I thought maybe I had an exhaust leak or something, but when I found the AIS valve, I figured that was probably the source of my smell as well. I don't think the plastic silencers have melted tho - unless they melt from the inside or something - outwardly they look fine anyway. I have to drive it till I get my wagon back, so I hope it doesn't melt them in the meantime - I've been driving it this way for a week or so, and just now had the time to take a look. It ran fine when warm, so I figured maybe the choke was malfunctioning, and put off looking into the problem longer than I should have probably. Hopefully any peices of plastice that made it into the intake didn't hurt anything. I guess they would just melt, and be thrown out the exhaust anyway.

 

I remember that big discussion we had - it did make it into the archives as I recall - I'll try to find it, and post the part number from there.

 

GD

The plastic parts do seem to melt from the inside. You might put a screen over the intake of the carb to keep from swallowing any more chunks of plastic. This cost my son a carb re-build since the plastic got in deep enough to prop the throttle open and over rev the engine.

Yeah - I consider myself lucky to have caused as little mayhem as possible in my carb - seems to run just fine still. I think I will go put the screen on it anyway - leave it there for good I think maybe.

 

GD