L20b ring gaps

[kelowg]

What is the ring gap suppost to be. Inch or mm. Manual says .009 to .0156 or something like that

[datsunaholic]

Inch. You'll never find a .009mm feeler blade...

 

.009 mm is 1/8th the thickness of a sheet of 16# paper.

[kelowg]

So what do u guys set them too?

[Jayden71]

.009inches??

[datsunaholic]

.015. I like them not dead on minimum. .009 is too close for a L20B.

 

Factory manual for an L20B top ring is .0098-.0157. That's .010-.016 on feeler blades.

2nd ring is .0118 to .0197, whoch is .011 to .020 on feeler blades.

 

Oil rings are .011-.035, BIG range there. But I set everything to .015. .015 blade goes in, .016 doesn't.

[I'm BLUE]

Also as a side note..

Make sure when you're compressing your rings

The oil-ring's don't jump the gap ! ( as in over-lap )

"Grant" brand rings purposely color one end of the control ring *Green* and the other ring end *Red* as a teller for this very purpose.

If it jumps .. likely that cylinder will eat oil like it's going out of style.

[kelowg]

Black ring and bore facing edge painted/coated silverish white. Marked on one side with a N. What the hell is that all about?

[kelowg]

Coated ring is a hair smaller uncompressed

[I'm BLUE]

Black ring and bore facing edge painted/coated silverish white. Marked on one side with a N. What the hell is that all about?

 

Depending on the piston ring itself..

probably indicator of piston ring direction = "This side up/This side down"

 

grab the instruction's the piston ring's came with to verify :)

 

It takes me a while to check ring-gap then lightly grind down piston ring edges ( if gap is too tight )

then check again carefully ... and be satisfied at the same time lol.

quality piston-ring grinder is worth it's weight in gold is all I have to say.

Some old timers just use files ( I can't keep it straight enough when I've tried ).

[kelowg]

No paperwork with them damn it

[I'm BLUE]

errrrrr that sucks.

 

I would advise stopping until you're 100% sure and seeing if you can research or look on a website/call someone.

 

my "assumption" is that if no other markings on the rings themselves ...

 

then N = "up"

 

But again I am assuming and assuming without fact is best to avoid when possible .

 

Some rings are literally marked "TOP" or "T" or ... how the manufacturer see's fit to mark the direction :unsure:

 

 

Hopefully the if you have some still in the package , and they haven't been touched take a quick look to see which way is up ( specifically the "N" marking ) ( piston rings should be in order per set and direction .. I think !? )

[datzenmike]

Top ring.... 0.0045" for every inch of bore. 86mm = 3.388 X 0.0045 = 0.015" This is about right for what Doug likes

2nd ring.... 0.0055" for every inch of bore. 86mm = 3.388 X 0.0055 = 0.018"

[datsunaholic]

Oh, and don't file ANY rings until you've tried them in the cylinders. You might find one fits one cylinder better than the others.