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-   -   Nikki accell circuit ball bearing weights - help with ID (https://www.rx7club.com/general-rotary-tech-support-11/nikki-accell-circuit-ball-bearing-weights-help-id-1086016/)

boyrotor 07-02-15 04:56 PM

Nikki accell circuit ball bearing weights - help with ID
 
So i've got my Nikki in a thousand pieces ready to go back together, reading the factory rebuild manual and noticed i have both the ball bearings for the accell pump circuit but dont have either of the weights. So either i managed to somehow not lose either ball and lose both weights (seems unlikely) or they were missing, or the version of Nikki didnt have them (seems unlikely - rx2 Nikki?).

I found something that looks like it might be one in a jar of bits i got somewhere along the line. Can anyone confirm the below is what i think it is and is it for the intake or outlet side of the circuit?

Dimensions; 9.07mm long, 2.22mm diameter (shaft)

http://iforce.co.nz/i/mptqzk3w.dio.jpg

garagemahal76 08-20-15 11:03 AM

that's just a needle for the float mech. for the accelerator pump itself, the brass weight looks about the size of #2 pencil lead thickness, and about 4mm long. the brass weight at the nozzle in carb is about 3mm thick and 4mm long cylindrical as well. you might be able to use brass stock ( kinda like music wire but solid brass) from a r/c hobby shop and cut to length. best of luck, I have 3 nikkis and only two are useful as both of my weights are gone to the depths of my garage somewhere. compressed air from teardown shot them to who knows where.

Jeff20B 08-20-15 03:42 PM

Could you just use that little brass insert from a needle after you cut off the head? Is it so different from the little brass weight? I don't think so.

I'll look through my Nikki parts and see whether there are any glaring differences preventing one of these needle inserts from being used as a checkball weight. Probably get back to this thread this evening.

boyrotor 08-23-15 09:09 PM

Thanks, yeah worked out what that was in the end.

But going over my photos from disassembly there definately were no weights over the ball valves in the accell pump circuit, either on the intake or exit. Is it possible this Nikki version (73 rx2) didnt use the weights?

lastphaseofthis 08-24-15 07:33 AM

Faced the EXACT same problem last week... thinking maybe my car was already torn into before...

i had my balls. but no weights. so i cut down a spring from a ball point pen, that fit on the outlet ball...

the other i cut down some aluminum filler wire of about the right thickness. now the accel pumps a good squirt again... the other issues, have got me wanting to ditch it for efi...

Jeff20B 08-24-15 12:04 PM

lastphaseofthis, maybe someone who works on Nikkis a lot could take a look at yours?

boyrotor, I am pretty sure all Nikkis from any year had the weights. I've come across carbs that didn't have them and usually could find a spare in my pile of Nikki parts. However these days those spare parts are drying up. Otherwise I'd offer you one.

Do what I suggested earlier or what lastphaseofthis suggested about using something else above the ball.

boyrotor 08-25-15 03:30 PM

Did they run ok without the weights? I noticed also the replacement ball for the outlet side is a lot larger from the rebuild kit as opposed to the factory item, may be enough extra weight on its own.

Jeff20B 08-26-15 12:09 AM

Hmm, now that's a thought, but I'd still use the factory item.

Idea: maybe place the replacement ball on top of the factory ball? The factory ball is correctly sized for the hole/cup shape it fits into. But above it is probably enough room for a slightly larger ball to act as a weight.

boyrotor 08-30-15 04:24 PM

Ok so i had another look and the carb definately does not use weights. On the intake side there is a rod pressed into the retaining screw, the assembly is approx 41mm long and leaves around 1mm clearance between its self and the check ball.

On the outlet there is around 2.5mm clearance between the retaining screw/banjo bolt and the new larger ball.

I tested the system with some kero in the float bowl and it works fine (with extended linkage mod and accell pump spaced out with .040" ali spacers on each side of the diaphram)


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