J engine ring end gap

Scirocco
Offline
Premium Member
Never change a running system
Posts: 4411
Thanks: 2263

Re: J engine ring end gap

27 Jul 2018 15:26 - 27 Jul 2018 15:28

#787756

SWest wrote:
Looks like wrong crosshatch. What do the rings look like?

This requires to pull the head, i would bit the bullet to confirm the scorings on the rings and pistons.

My 1975 Z 1 B 900 Project

www.kzrider.com/forum/11-projects/605133...ears-deep-sleep-mode

Last edit: 27 Jul 2018 15:28 by Scirocco.

Please Log in or Create an account to join the conversation.

SWest
Offline
Sustaining Member
10 22 2014
Posts: 23336
Thanks: 2877

Re: J engine ring end gap

27 Jul 2018 15:40

#787757

Looks like the head is already off. Is it a overbore? If so it was a lousy job and the hone wouldn't clean it up. I suspect particles of metal scored the bores.
Steve

Z1b1000 1975 Z1b
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229

Please Log in or Create an account to join the conversation.

Scirocco
Offline
Premium Member
Never change a running system
Posts: 4411
Thanks: 2263

Re: J engine ring end gap

27 Jul 2018 15:53 - 27 Jul 2018 15:56

#787758

Could be an endoscope view through the spark plug bore.
VTEC know the answer.

My 1975 Z 1 B 900 Project

www.kzrider.com/forum/11-projects/605133...ears-deep-sleep-mode

Last edit: 27 Jul 2018 15:56 by Scirocco.

Please Log in or Create an account to join the conversation.

SWest
Offline
Sustaining Member
10 22 2014
Posts: 23336
Thanks: 2877

Re: J engine ring end gap

27 Jul 2018 15:58

#787759

In any event the horizontal grooves would cause ring "chattering." My next question would be the piston/wall clearance.
Steve

Z1b1000 1975 Z1b
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229

Please Log in or Create an account to join the conversation.

SWest
Offline
Sustaining Member
10 22 2014
Posts: 23336
Thanks: 2877

Re: J engine ring end gap

27 Jul 2018 16:19

#787762

After looking at it again it looks like the marks stop at the top ring. Must have happened after first install.
Steve

Z1b1000 1975 Z1b
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229

Please Log in or Create an account to join the conversation.

VTEC
Topic Author
Offline
User
Posts: 558
Thanks: 80

Re: J engine ring end gap

27 Jul 2018 18:46

#787772

Engine is still together. Pics are with a borescope through the plug hole. Marks go all the way to the top of the bore, above the top ring. Not there on assembly.

KZ1000-K2
ZRX1100
XR400R

Please Log in or Create an account to join the conversation.

SWest
Offline
Sustaining Member
10 22 2014
Posts: 23336
Thanks: 2877

Re: J engine ring end gap

27 Jul 2018 18:50

#787773

I'm afraid you're going to have to open it back up.
Steve

Z1b1000 1975 Z1b
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229

Please Log in or Create an account to join the conversation.

VTEC
Topic Author
Offline
User
Posts: 558
Thanks: 80

Re: J engine ring end gap

27 Jul 2018 19:35

#787775

SWest wrote: I'm afraid you're going to have to open it back up.
Steve

I know. Really sucks. Just want to be sure of the cause so it doesn't happen again.

KZ1000-K2
ZRX1100
XR400R

Please Log in or Create an account to join the conversation.

SWest
Offline
Sustaining Member
10 22 2014
Posts: 23336
Thanks: 2877

Re: J engine ring end gap

27 Jul 2018 19:47

#787776

Should be obvious.
Steve

Z1b1000 1975 Z1b
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229

Please Log in or Create an account to join the conversation.

zed1015
Offline
User
Posts: 3129
Thanks: 1736

Re: J engine ring end gap

28 Jul 2018 01:02

#787782

Were the bores washed with clean soapy water after boring and not just solvent ?
If not it's scuffing from the honing grit still trapped in the hatching.

AIR CORRECTOR JETS FOR VM CARBS AND ETHANOL RESISTANT VITON CHOKE PLUNGER SEAL REPLACMENT FOR ALL CLASSIC AND MODERN MOTORCYCLE CARBURETTORS
www.kzrider.com/23-for-sale/611992-air-c...lide-mikunis?start=0

Please Log in or Create an account to join the conversation.

VTEC
Topic Author
Offline
User
Posts: 558
Thanks: 80

Re: J engine ring end gap

28 Jul 2018 04:32 - 28 Jul 2018 04:34

#787785

zed1015 wrote: Were the bores washed with clean soapy water after boring and not just solvent ?
If not it's scuffing from the honing grit still trapped in the hatching.

Yes, I scrubbed the hell out of them. But I did have an issue with flash corrosion within a minute of washing before I could get them dry. Rubbed them down with ATF to take it off, but if you look closely you could still see a hint of rust color. Everybody said don't worry about it.

You think fuel wash or a heat issue could have caused this?

KZ1000-K2
ZRX1100
XR400R

Last edit: 28 Jul 2018 04:34 by VTEC.

Please Log in or Create an account to join the conversation.

zed1015
Offline
User
Posts: 3129
Thanks: 1736

Re: J engine ring end gap

28 Jul 2018 05:30

#787788

Must have been very cold/ damp to cause that but slight brown staining shouldn't have done anything.
As regards the cause ,who knows ? without pulling it apart but If it runs ok otherwise I would give it a chance and do a few hundred miles and see if it settles.
20 miles isn't enough for a determination unless something drastic happened.

AIR CORRECTOR JETS FOR VM CARBS AND ETHANOL RESISTANT VITON CHOKE PLUNGER SEAL REPLACMENT FOR ALL CLASSIC AND MODERN MOTORCYCLE CARBURETTORS
www.kzrider.com/23-for-sale/611992-air-c...lide-mikunis?start=0

Please Log in or Create an account to join the conversation.