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Re: Fuelling?

Posted: Thu Sep 13, 2012 3:24 pm
by Mang
Maelstrom

Your point is totally valid as I note my carbs do not have ANY Needle jet O rings! I take it that the O ring sits below the white nylon washer ring which sits below the circlip on the needle. I have tried to attach a diagram. didnt work (can anyone explain to an old fart how to do this)

I obviously need to buy some of these O rings and note that there are a number of sellers online, does anyone have a description or catalogue number for the O ring and a recommendation of a supplier.

I guess fitting these in light of your comment would be a good start!!!!!!!!!

Re: Fuelling?

Posted: Thu Sep 13, 2012 7:18 pm
by Hogdigerdy Dog
Kurlon wrote:We have the 'Power Jet' which could be a 97.5 or 100

in fact it should be both :grin:
no1 and no4 should be 100
no2 and no3 should be 97.5
as the inner 2 cylinders get hotter, and this affects the mixture
strip the carbs you got and check out the manual, make sure everything is standard (as said before) and go from their,
second hand carbs are stupid money, and unless the housing is bust you can re-build em, for a fraction of the price,

Re: Fuelling?

Posted: Fri Sep 14, 2012 4:53 am
by Maelstrom
I am with Hogdigerdy Dog, best to give your carbs a full make over, and then you know they are good to go. Who knows how old some of your o-rings are?

The slide runs in a plastic housing that fits down onto the base of the intake throat. Underneath that housing is an odd size o-ring that seals around the top of the needle jet (Part No. 1AE-14147-00). The parts diagram does not show the location of this o-ring very clearly. To the best of my knowledge you cannot buy fully comprehensive carb kits at this time. However, you can buy individual o-rings and seals as genuine parts. Keyster make kits (K-688) that include most of what you need. Not what I would like to pay that much but then I'm old.

At the moment I am in the process of putting together fully comprehensive kits for these carbs. Some of the items, like the fuel seals, are proving to be difficult to produce in small enough quantities. As an example, I do not believe I could ever sell 43,000 fuel seals. This problem is mainly self inflicted because I refuse to use NBR, and in many cases I have to pay for Viton by weight.

I have divided the kits into three parts.
A - All carb seals including choke plunger seal.
B - All fuel seals.
C - Throttle Shaft seals and screws.

I have not made this page (http://litetek.co/Carb_Kit_Yamaha_3TJ1.html) accessible on my web site since the kits are not ready yet, but it will help you with all the part numbers and might clear up a few grey areas. There is also a pdf of the part numbers that I will be using, and the original Yamaha part numbers are on the web page.

With regard to your problem, I am expecting to have the basic o-rings for the carbs within the next week. Although the molds for the float bowl o-ring and the jet housing o-ring are finished, I have not given the go ahead for production yet as I am waiting for samples to arrive.
Thus far, everything I have produced is in Viton not NBR.
I am also doing comprehensive V4 Honda kits in case you own one of those.
These kit details are obviously a bit premature, and this thread is not the correct place for all these details, so if you need more info please pm me.
Hope this helps
Blair