Cracked Diaphragm

While I was tearing into my carbs tonight I notice that on one of the diaphragms the plastic ring had a small piece missing out of it. Is this normal? Is it going to cause a problem? Is it an expensive fix? This is not a picture of mine, but mine looks exactly like this one and it also looks to be in the same exact carb.

 

Yep, that'll probably cause a problem. If you've taken the other carb hats off, you'll see that the other diaphrams are not like that. I have good used piston/diaphram units available, diaphram still flexible, no hole (not even pinholes!) in the rubber. Send me a PM if interested!

 

Did you notice the "after" picture?

I lit the end of a heavy nylon wire tie and dripped the nylon in there. Then I filed smooth. You'll notice the blistering around the top of the ring, got it too hot and set the little ridge on top of the ring on fire. I believe I may have used locking pliers to hold the ring snug against the piston.

Repair was in service all last summer, no problem. Haven't pulled the hat yet this winter to check on the repair.

 

Wow, nice job. I'd say something pithy like "MiCarl, you're playing with fire" in attempting to repair things that way, but......it's literally true. And it seems to have worked!

 

My motto is to never do a job right, or with the proper tool, when fire is an option

 

My motto is "Everyone Needs A Motto."

 

I should probably add that Burning nylon is extremely nasty stuff. You can be severely burned!

I also have very little doubt that if it gets dripped on the diaphragm it will burn right through it.

 

Just wanted to revive this thread really quickly-- im back into my carbs again and tho i saw this on 2 of my diaphram previously it didnt really register in my brain... i assume the problem would be vaccuum leaks... and well, replacing those pistons is cost-prohibitive at the time... MiCarl- how did your repair hold up, i see you sold the bike, did you ever check them out before selling? Is it really worth messing with? the risk i mean of F-ING up the rubber? cause the bike has been running strong previously, just lean but EVENLY lean between all 4 cylinders...Opinions?