Topic: 750K 77 petcock rebuild - what is proper assembly?

[Erny]

I need quick help for petcock reassembly (i purchased rebuilt kit)

There is spring and plastic washer. I did not pay attention when I disassembly it...

What is proper order to assemble it?

I suppose rubbber gasket first into petcock body, then spring, swith, plastic washer (to ease switch movement), cover.

Picture attached - is it correct like that?
Shall I lubricate it too before assembly?

Another issue is that new rubber is significantly ticker, old is 2.63, new 3.29mm. Hope this is normal?

[Alaxy Galaxy]

I need quick help for petcock reassembly (i purchased rebuilt kit)

There is spring and plastic washer. I did not pay attention when I disassembly it...

What is proper order to assemble it?

I suppose rubbber gasket first into petcock body, then spring, swith, plastic washer (to ease switch movement), cover.

Picture attached - is it correct like that?
Shall I lubricate it too before assembly?

Another issue is that new rubber is significantly ticker, old is 2.63, new 3.29mm. Hope this is normal?

I'm not sure the plastic ring, but I'm 100% sure the metal "spring ring" goes on the outside of the moving tap, between it and the name plate. Its purpose is to push the moving tap against the rubber valve.

[Erny]

Thanks, you are right
I think I found info how it should be, both plastic ring and spring goes between switch and cover plate, details here
http://hawkworks.net/tips/leaky-petcock/

[madmtnmotors]

From the inside out:

>Seal goes in the valve body
>Then the "handle"
>Then the plastic washer
>Then the spring washer
>Then the outer plate

The valve/handle bears against the seal to prevent leaks. The plastic washer serves as a buffer between the valve handle and the spring washer.

EZPZ

Here is an excerpt from my "Evolution" build thread:


Contrary to popular belief, the later model fuel valves can be rebuilt:



Can anyone tell which one is the new seal?



Leave as much of the nubs as possible. I carefully pried up on the rolled edge of the rivet with a razor knife until I could free the outer plate:



Voila'! (as opposed to "viola'" which everyone knows is a musical instrument) 



Good for another 40 years! Good thing too, since this can only probably be done once, which is okay... because 40 years from now I won't care!

[Erny]

Thanks, do you know by chance dimensions of gasket between petock7and tank? See my other thread

[Vin750]

I need quick help for petcock reassembly (i purchased rebuilt kit)

There is spring and plastic washer. I did not pay attention when I disassembly it...

What is proper order to assemble it?

I suppose rubbber gasket first into petcock body, then spring, swith, plastic washer (to ease switch movement), cover.

Picture attached - is it correct like that?
Shall I lubricate it too before assembly?

Another issue is that new rubber is significantly ticker, old is 2.63, new 3.29mm. Hope this is normal?

I'm not sure the plastic ring, but I'm 100% sure the metal "spring ring" goes on the outside of the moving tap, between it and the name plate. Its purpose is to push the moving tap against the rubber valve.

How do you make sure the outer plate holds it together? Do you re rerivett it?


Sent from my iPhone using Tapatalk Pro

[Vin750]

I need quick help for petcock reassembly (i purchased rebuilt kit)

There is spring and plastic washer. I did not pay attention when I disassembly it...

What is proper order to assemble it?

I suppose rubbber gasket first into petcock body, then spring, swith, plastic washer (to ease switch movement), cover.

Picture attached - is it correct like that?
Shall I lubricate it too before assembly?

Another issue is that new rubber is significantly ticker, old is 2.63, new 3.29mm. Hope this is normal?

Where do you get the new rubber seal from?


Sent from my iPhone using Tapatalk Pro

[brewsky]

I need quick help for petcock reassembly (i purchased rebuilt kit)

There is spring and plastic washer. I did not pay attention when I disassembly it...

What is proper order to assemble it?

I suppose rubbber gasket first into petcock body, then spring, swith, plastic washer (to ease switch movement), cover.

Picture attached - is it correct like that?
Shall I lubricate it too before assembly?

Another issue is that new rubber is significantly ticker, old is 2.63, new 3.29mm. Hope this is normal?

I'm not sure the plastic ring, but I'm 100% sure the metal "spring ring" goes on the outside of the moving tap, between it and the name plate. Its purpose is to push the moving tap against the rubber valve.

How do you make sure the outer plate holds it together? Do you re rerivett it?


Sent from my iPhone using Tapatalk Pro

I started the same thing for my 78 (nla), but found this replacement for 17 bucks.....works great.....and, it comes with a new tank gasket.

http://www.vintagecb750.com/search/?q=petcock

You could drill and tap a screw or drill thru and use small bolt to secure the old one.

[madmtnmotors]

Where do you get the new rubber seal from?

Honda still makes them. They are the same seal as the earlier models with the screw-on retainer plate. Honda P/N 16955-268-020


https://www.partzilla.com/product/honda/16955-268-020?ref=9a5b1213b920bbd3a97a7ebe4674b3f02374a777

[Erny]

Sh*t... Knowing that 2 months ago. I purchased from ebay kit https://m.ebay.com/itm/HONDA-FUEL-PETCOCK-REBUILD-GASKET-KIT-XL250-XL250S-XL350-CB400-CX500-CB750/121280660721?hash=item1c3ce404f1:g:tkIAAMXQEgpTCBDL having that seal, 2 M3 screws and one more O ring (maybe this one is intented to be seal beween petcock and tank???)

Now I see I overpaid it a lot.. Screws cost nothing, and not sure that O ring is usable as gasket (as should be flat?)

[Erny]

I need quick help for petcock reassembly (i purchased rebuilt kit)

There is spring and plastic washer. I did not pay attention when I disassembly it...

What is proper order to assemble it?

I suppose rubbber gasket first into petcock body, then spring, swith, plastic washer (to ease switch movement), cover.

Picture attached - is it correct like that?
Shall I lubricate it too before assembly?

Another issue is that new rubber is significantly ticker, old is 2.63, new 3.29mm. Hope this is normal?

I'm not sure the plastic ring, but I'm 100% sure the metal "spring ring" goes on the outside of the moving tap, between it and the name plate. Its purpose is to push the moving tap against the rubber valve.

How do you make sure the outer plate holds it together? Do you re rerivett it?


Sent from my iPhone using Tapatalk Pro

I drilled 2 2.5mm holes and tap M3 inside