Question about carb holders

I have been chasing an air/vacuum leak since I bough my bike (77 kz650). I pulled a couple of the carb holders and they are cracked but it doesn't look like it's cracked all the way through. Should I be good to go ahead and use these or should I go ahead and replace them. I don't think they are leaking since the Crack aren't all the way through but I figured I would get some input

They are hard and will leak. This time around I sealed them with :ohmy: Permatex. It worked (kinda) and I ordered new ones. Put them on, everything changed. I already knew it would. :blush:
Steve

Which permatex product did you use? Gasket maker?

I hate that stuff. Do not use it on anything else or you'll regret it later. It's in a small bottle with a brush. When you get them off again, you'll have to scrape it off.
Steve

Eh sounds like nasty stuff but I may not have a choice right now. Don't really have $90 to drop on carb holders right now

Know how it is. Lasted me long enough to get some. $5 vs $90= $5 :whistle:
Steve

Replace them - period. Tiny cracks on the mating surfaces where the carb holders seal against the cylinder head will cause problems. They can be so small that you may not even be able to see them without magnification; I found this to be the case on my 1977 KZ650-C1. Removing the carbs and putting goop on there to seal them is at best a very temporary measure that's barely worth the work involved, and at worst you run the risk of that goop being sucked into the engine. Replacement is the way to truly correct the problem. $70 but well worth it. Ed

Sometimes you have to make do with what you have. A light coat of sealant is NOT going to cause problems. It's a temporary fix at best. It has been acknowledged they need to be replaced. Chances are other things will as well. :whistle:
Steve