"O" ring for NT carbie

DAMIEN1307

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Hi folks,

I have seen here in the forums where an "O" ring is recommended to be placed on the intake tube for the carbie to fit over to minimize possibility of excees air induction etc.

Exactly what gas resistant type of "O" ring are we talking about as well as thickness, diameter, where to get it, (is it available at small engine sales and service store), What do i ask for, where and how to place it, does it need any lube, or adhesive etc.

Need to know since i have never heard of, or done this before,

Any info. for this would be welcome...DAMIEN
 
I bought the sets of Harbor Freight O rings in both SAE and Metric. I used a 18.6mm od - 13.8mm id. You get 10 or 12 of them in the kit.
 
Years back the auto stores had the green one’s they were the fuel and oil resistant one’s. I bought about 10 of them. I haven’t bought any since. They might be all black now. If that helps.
 
Thanks all who responded on this and especially,
Years back the auto stores had the green one’s they were the fuel and oil resistant one’s. I bought about 10 of them. I haven’t bought any since. They might be all black now. If that helps.
I also seemed to remember the difference from my automotive days of that difference and vaguely remembered about those off green coloured ones for gas/oil usage.

I talked to one of our "youngsters" at church this morning about them since he works at our local Western Auto/True Hardware store here in Alamogordo, NM, and he told me that, Yes, they carry them and come in to see him tomorrow, so off i go in the morning...thanks to all again...DAMIEN
 
most o rings are nitrile (NBR or BunaA) it is gas and oil resistant. They can come in any color.. red, green, orange.. etc. (mine are black)
100676


other material worth mentioning
HNBR - oil resistance and higher temp to 340F / 175C (mine are green)
Viton - oil resistance high temp to 430F / 220 C (I have brown ones)

Silicon - not recommended for oil use
 
Viton is also ethanol resistant and is pretty much what comes in most carb rebuild kits these days.
 
Last edited:
Viton is also ethanol resistant and is pretty much what comes in most carb rebuild kids these days.
Good to know about "ethanol resistant" although im using ethanol free gasoline because 2 cycle engine seals tend to be problematic with ethanol gas usage...DAMIEN
 
I use the nitrile orings and have yet to have them melt or deform in any way. I save the viton for where there’s a little higher temp requirement.

100708
 
I got them from SICK BIKE PARTS and I also put one where the throttle cable hooks up to carb in the screw cap it is the same diameter
 
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