O-rings

I have replaced the o-rings on the T fitting between my carbs on my KZ305 at least twice. They will seal alright for a couple of days and then start to leak. I am using regular black o-rings out of a metric assortment that I have. Just wondering if there is a special type I should be using? I don't really want to do this again.

make sure your carbs are clean then put them together with sealant. i did this 2 years ago and not one leak since. just my 2 cents worth.

What kind of sealant did you use?

It's hard to find for all applications, but * viton * o-rings are supposedly impervious to fuel and other nasties. The better carb kits contain 0-rings made of this material. fyi...and good luck.

Like Neil said, "Viton" is what you want. Viton is a Dupont fluorocarbon elastomer. There are some other names for the same stuff made by other companies.

Buna N, (aka nitrile or nitrite) is not as good, but more commonly found in generic sizes.

Here's a place that sells some hard to get Viton orings. They have some oddball Honda sizes, but they have pretty accurate description of the sizes. (I just ordered a bunch of small orings from them,... very good service.) Usually you get an ID (inside diameter) and cross section (thickness of the rubber).

www.crc2onlinecatalog.com/gl_carb_parts.htm

Yeah, the ones I have are nitrile. I kinda wondered if they would hold up (guess i know now). Think I will try to find some Viton ones. If I remember right from my automotive experience they are red? Anyway thanks for the replies.

del

The industry, at one point, made some sort of attempt at making a color ID for oring materials, but it didn't really work. Viton comes in several colors, but black seems most common. Brown Viton is supposedly the same as black Viton other than the color.