Should there be play on the carbs nylon washer ?

Hi,

Another post to quickly ask if there should be this much play on the nylon washers or are mine just worn off and if the case which should i change to make sure i get the butterfly valve centered as it is.

I have this issue on carb 2 and 3 but not on carb 1 and 4
here's a pic of the gap when fitting it all without the seals

 

I can see Xj4ever sells these but unfortunately i can't order these from where i am (Finland), would anyone know the proper thickness these are supposed to be?
Then i can source a replacement locally with the inner and outer diameter

bbb) Aftermarket Hitachi HSC32/33 series carb Throttle Shaft Seal PLASTIC SHIM WASHER...these washers go directly "outside" of the HCP904 o-rings or the HCP38B v-seals listed above. Same notes as listed above about the seals (regarding the ease of replacement) also applies to these shims. NOTE: these shims do NOT "wear out" like the seals do; you only need to replace them if your shim washers are broken or missing. ALSO: although these replacement shims have the correct O.D. and I.D. as the originals, they are only 1/2 the thickness of the originals, and thus you will have to use two (2) of these shim washers to replace one (1) original shim washer.

HCP39C Aftermarket Hitachi throttle shaft seal Shim Washer, single:
$ 2.00

HCP39CSET2 Aftermarket Hitachi throttle shaft seal Shim Washer, pair:
$ 3.75

HCP39CSET4 Aftermarket Hitachi throttle shaft seal Shim Washer, four shims:
$ 7.25

HCP39CSET16 Aftermarket Hitachi throttle shaft seal Shim Washer, sixteen shims:
$ 20.00

 

Can you get them from https://www.cmsnl.com/ l don't know the dimensions of the parts. Someone will.

 

I tried to look for it there, but on the exploded view of the carbs I can't find the washer number...

Manu

 

I am wondering if they can be reused. @Jetfixer has replaced seals. Don't know if he replaced washers.

 

https://images.cmsnl.com/img/partsl...4k0-300e1-carburetor_big3IMG00996396_3534.gif on this I can't find it.
You're right they should be reusable but they seem to have lost thickness.

 

I don't know if that matters too much. @hogfiddles rebuilds loads of carb racks he will know.

I have not rebuilt carburettors yet, well throttle shaft seals l mean. Have the washers lost thickness or have the seals deteriorated making it appear the washers have lost thickness? Don't know if that is possible just saying

 

Great, maybe he can shine a light, I don't think it will matter much in the sense that the seal itself needs to seal. the washer acts as dust seal and obviously once the butterfly is in place it can rock sideways
Maybe I just go with it and see...
I am really losing confidence on this bike. I hope I get to turn it on again

 

Persevere you will get it fixed. You don't want the washers too thick because that may prevent the throttle shafts shutting properly. My guess is there is meant to be some clearance when it's all assembled. The only surface contacting the bore of the seal is the throttle shaft. It has to be tight enough to seal without any binding. Thick washers if they could put side pressure on the seals would not be good l think. Hogfiddles and Jetfixer will let you know what to do.

 

The 900f uses Mikuini BS 36 carburettors but this link is for Hitachi if you want to have a read. Must be lots of similarities.


https://redirect.viglink.com/?forma....xj4ever.com/hitachi throttle shaft seals.pdf

 

@Mezzmo did you replace the throttle shaft washers when you rebuild your carburettors?

 

Hi Franz, no I didn’t replace the washers. Just all rubber seals, gaskets and jets…the shaft washer thickness is not that critical as the shaft seal does the work and the butterfly maintains the shaft position, not that washer. In fact I think you will find there needs to be some clearance so it moves freely. I wouldn’t replace unless there are broken..

 

Yes this is an amazing pdf, that's the one I am following along with a YouTube video.
Maybe I'll go ahead and put it all back together as is

 

I borrowed your video Mezzmo . I didn't think they needed replaced.

 

I don't think you will have any problems with the existing washers.

 

I thought some clearance with the washers would be necessary too to prevent throttle shaft binding.

 

When I rebuild for a customer, new ones go on.

if I rebuild just for myself, I’ll go with new ones.if just a Shim washer is needed, I’ll use used ones... I got a gazillion of them as spares

 

Wow thank you all. @Mezzmo That video series is incredible btw. Thank you for doing it, it's helped me so much.

I moved forward and reassembled the carbs now, didn't put all float bowl screws as I need to get new ones and have to adjust the floats.

When tightening the bolts on the throttle shafts the gap became a little smaller. I'd say there is 1-2mm max play on carb 2 and 3

Seals are new and carbs are all internally cleaned.
Only think is a messed up one throttle shaft seal when inserting it... Have to order one more.

Not to self, always order extra part.

@hogfiddles hope ill be fine with old ones

 

from xj4ever catalog

NOTE: these shims do NOT "wear out" like the seals do; you only need to replace them if your shim washers are broken or missing.

 

You’ll be fine as long as they aren’t broken or worn down. Wearing down is rare....the only ones I find that are worn down are one that have had this series of event:
-the throttleshaft seals get sticky
-the shim washers get stuck to the sticky seal
-the sticky seal goo hardens over time
-the shim washer is now stuck to hardened goo
-the shim washer no longer rotates
-the E-clip now wears down the shim washer

dfox

 

Very good info thanks !

Manu