Piston rings

arcturus · Jul 12th, 2017, 10:55

Hi, I believe that they have sent the wrong piston rings. As you can see from the pic' there doesn't seem to be enough room for the spiral (oil ring) and spacers. of have I got it wrong. The blurb with the rings says fit spacer first, then spiral and then other ring. it can't happen.
Secondly, ring tool, can't figure out how it works. Seems to compress rather than open rings.

OK. Crisis over. I either miss read the blurb or it was wrong. One piston done, the rest should be a piece of cake

When I removed No. four piston I found a broken top ring. no scoring on bore that I could see

Ron Kwas · Jul 12th, 2017, 14:12

Arcturus;

It looks like that tool is configurable to both compressing and expanding rings (although I cant quite think of what one might want to compress rings for...maybe filing to adjust gap) by sliding and relocating the fulcrum...but I guess you figured that out...

Finding a broken Ring is not uncommon...it must not have been broken too long because thankfully you did not find an associated score in the bore (which rather necessitates a rebore).

Cheers

Derek UK · Jul 12th, 2017, 19:52

Broken ring makes a good scraper for getting the carbon out of the grooves. Cleaning off all of the carbon is good as long as you don't damage the piston, but I've a feeling that some will say that the carbon above the top ring will improve the seal. If removed that will have to build up again. Are the bores going to be honed to give an even cross hatch? That is needed to run in the new rings.

arcturus · Jul 12th, 2017, 21:48

Don't have access to a honer. How essential is that. Would 800 / 1200 rubbing paper work?

amazon69 · Jul 12th, 2017, 22:40

Here's one. They come in different sizes (the link is not necessarily the correct size). Work a treat.

dingov70 · Jul 12th, 2017, 23:22

Rings very often break when the piston is pushed from the cylinder , the ridge / lip on the cylinder top causes the breakage. Bores definately need to be honed when installing new rings , this allows extra oil to be held on the cylinder wall & help with the running in process .

A grit of 800 /1200 is far too fine and it will never provide a suitable surface finish . I used 240 grit or slightly finer & lubricate with paraffin to remove debris , you are aiming to produce a 45° angle cross hatch EVENLY over all the cylinder wall .

arcturus · Jul 13th, 2017, 09:27

Ordered one. No point in sinking the ship for a hap' worth of tar!

Derek UK · Jul 13th, 2017, 10:54

https://www.youtube.com/watch?v=ZafrlCsnCLs

Before I read the comments on the video I did think that the drill speed looked a bit high. That does get a mention, along with other things.

arcturus · Jul 13th, 2017, 12:29

It's a steep learning curve but at the end of the day it's not rocket science. A lot of mystique but mostly spanner work and common sense.

Jul 12th, 2017, 21:48	#4
arcturus arcturus Last Online: Today 07:30 Join Date: Mar 2006 Location: Sagres Portugal	Don't have access to a honer. How essential is that. Would 800 / 1200 rubbing paper work? __________________ life's too short to drink bad wine

Jul 12th, 2017, 22:40	#5
amazon69 Premier Member Last Online: May 13th, 2024 11:44 Join Date: Jan 2006 Location: Falmouth	Here's one. They come in different sizes (the link is not necessarily the correct size). Work a treat. __________________ Falmouth, Cornwall. 1970 California white 131.

Jul 12th, 2017, 23:22	#6
dingov70 Master Member Last Online: May 1st, 2024 06:42 Join Date: Jan 2015 Location: Blackpool	Rings very often break when the piston is pushed from the cylinder , the ridge / lip on the cylinder top causes the breakage. Bores definately need to be honed when installing new rings , this allows extra oil to be held on the cylinder wall & help with the running in process . A grit of 800 /1200 is far too fine and it will never provide a suitable surface finish . I used 240 grit or slightly finer & lubricate with paraffin to remove debris , you are aiming to produce a 45° angle cross hatch EVENLY over all the cylinder wall . __________________ To stupidity & beyond

Jul 13th, 2017, 09:27	#7
arcturus arcturus Last Online: Today 07:30 Join Date: Mar 2006 Location: Sagres Portugal	Ordered one. No point in sinking the ship for a hap' worth of tar! __________________ life's too short to drink bad wine

Jul 13th, 2017, 12:29	#9
arcturus arcturus Last Online: Today 07:30 Join Date: Mar 2006 Location: Sagres Portugal	It's a steep learning curve but at the end of the day it's not rocket science. A lot of mystique but mostly spanner work and common sense. __________________ life's too short to drink bad wine

Jul 12th, 2017, 14:12	#2
Ron Kwas Premier Member Last Online: Today 21:32 Join Date: Jul 2007 Location: Connecticut, USA	Arcturus; It looks like that tool is configurable to both compressing and expanding rings (although I cant quite think of what one might want to compress rings for...maybe filing to adjust gap) by sliding and relocating the fulcrum...but I guess you figured that out... Finding a broken Ring is not uncommon...it must not have been broken too long because thankfully you did not find an associated score in the bore (which rather necessitates a rebore). Cheers

Jul 12th, 2017, 19:52	#3
Derek UK VOC Member Last Online: Today 12:14 Join Date: Jul 2006 Location: Chatham	Broken ring makes a good scraper for getting the carbon out of the grooves. Cleaning off all of the carbon is good as long as you don't damage the piston, but I've a feeling that some will say that the carbon above the top ring will improve the seal. If removed that will have to build up again. Are the bores going to be honed to give an even cross hatch? That is needed to run in the new rings.

Jul 13th, 2017, 10:54	#8
Derek UK VOC Member Last Online: Today 12:14 Join Date: Jul 2006 Location: Chatham	https://www.youtube.com/watch?v=ZafrlCsnCLs Before I read the comments on the video I did think that the drill speed looked a bit high. That does get a mention, along with other things.

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