4 replies to this topic

[AndyR]

Hi Folks

 

I have my 1380 k 16v apart for some crank work, and thought i would go around checking the rest to see how she was doing.  It hasn't done more than 1000 miles since being built.  I was checking the ring gaps and they have come out at

 

Top Ring - 0.016"

Oil Scraper - 0.017

Oil Rails - 0.019"

 

cross the board.  All nice and consistent.  These were all measured an inch below deck.  I will re-check at the bottom of the stroke tomorrow.  If going from what they should be 0.009 - 0.014, they would be on the big size, especially the oil scraper as this runs cooler.

 

Does anybody know if these are still usable? Or would new rings and re-gapping work?  And then would i need to re-hone too?

 

Thanks

 

Andy

[Guess-Works.com]

5 thou per inch of bore is the rule of thumb.

 

However, were you burning oil or experiencing excessive crankcase pressure ?

 

But, as the engine is apart, rings are not that expensive so drop a new one down the bore and measure the gap, see if it's then worth honing for new rings, or buy some gapless rings and not worry about ring gaps any more.

[AndyR]

Well....i was going with the 3 - 4 thou, as i thought the 5 thou was for hotter running turbo engines.  5 thou doesn't make them too bad then.  It didnt use any oil if i can remember, however it did lose a fair bit to the catch tank, but this was fitted stupidly low in the engine bay.

 

If i were to achieve good gaps with a new ring set, would i need to rehone?  And how much would i lose in the hone process?  I like the sound of gapless rings though!

 

Thanks

 

Andy

[Spider]

ACL who did manufacture Rings, give 0.003" to 0.005" per inch of bore for 'Normal' street use Engines, however there are variations to this and this Tech Sheet gives some guidance;-

 

 

 

None the less, you would be wise to contact the manufacturer of the Rings you have a seek their guidance.

Edited by Moke Spider, 21 June 2015 - 10:35 PM.

[AndyR]

Cheers for the info guys.  I gave both SC who built the engine and omega a call today, sc set it up with 15thou, so 1 thou wear - not too terrible.  And Omega said their rings were good for 9 - 19thou top ring, 12 - 22 second and 16 - 28 for the oil rings.  So all within good range.  Will stick what i have back in, based on this advice.  Good for future reference too

 

Andy