chrome rings experiences, break in time

[prondzy 3,881]

5 hours ago, WHX24 said:

 

 

I must have read right by that one Mike. Any idea on the theory behind it? 

 

 

The engine is designed to run on sae 30 oil, gaps and tolerances are set for this weight oil. Multi weight oils are thinner when they are not to operating temperature so more gets past the rings than with sae 30

[bc.gold 3,403]

10 hours ago, Greentored said:

@bcgold i finished off with 280 grit stones, slightly 'rougher' than the 400/red scotch brite (yep!) I do on standard moly rings. Hopefully was coarse enough, wondering if I should've gone 220.

 

I'm not really into small engines, the few I have done, tanking, re-bore and cylinder hone to size for the piston was all on the machine shop work order.

 

You may find that two new pistons of the same manufacture may differ in actual size plus or minus, these differences are brought into spec at the honing stage.

 

Just because the cross hatch looks good does not mean the piston and cylinder are still within spec.

 

In the snippet below where it says 900 from the wrist pin, should have said 90 degrees, this is the widest diameter. Pistons are cam ground.

 

Credits with full article.

 

 

 

 

 

Edited January 19, 2021 by bcgold

[tom2p 2,394]

9 hours ago, Greentored said:

Stens rings, straight Valvoline VR1 racing 10/30.

 

The Bon Ami trick- basically, buy a box of it, dump it down the carb with the engine running.  Supposedly the mild abrasive will (help) seat rings. Yeah, I know- scary!  However, the general consensus seems to be much more positive than negative....

ouch - I would pass 

 

[Greentored 3,217]

12 hours ago, bcgold said:

 

I'm not really into small engines, the few I have done, tanking, re-bore and cylinder hone to size for the piston was all on the machine shop work order.

 

You may find that two new pistons of the same manufacture may differ in actual size plus or minus, these differences are brought into spec at the honing stage.

 

Just because the cross hatch looks good does not mean the piston and cylinder are still within spec.

 

In the snippet below where it says 900 from the wrist pin, should have said 90 degrees, this is the widest diameter. Pistons are cam ground.

 

Credits with full article.

 

 

 

 

 

 

You are absolutely correct, but if I cant mic a piston correctly after doing this for 30 years, it might be time to quit   I do wonder a bit about the choice of stone grit used to finish as I couldn't find much info on this and have almost zero experience using chrome rings. I know its a coarser finish, so I chose, hopefully not incorrectly.

I think you guys are onto something with the 10w30 vs 30w, but the strange thing is it is 'using' very very little.  Also, this 'puffing' I speak of is not a constant- there is absolutely zero smoke ever unless I 'goose' the throttle, and even then it is not making a cloud ha, just a blue 'puff' that is annoying......