273 302 318 340 build

273 302 318 340 build

No I definitely won' be guessing on orientation. I will call the machinist as mentioned. These were part of the pkg deal so no returning them. I'm confident if there is an issue that the machinist will straighten it out.
Perfectly fine muddying the waters a bit. I'm eager to learn. My hesitation comes from not knowing the exact mfg part# and following their specific install procedures.
As I mentioned the chamfers on both rings are same direction. What I have read is they should oppose. I agree they don' look like mily face rings.
Thanks guys

nm9stheham said
Don't ever guess on ring orientation. Find the data. The chamfers create what is called ring twist in the rings action in moving up and down the bores; they angle in their grooves a bit more going one direction than the other. While the chamfers may be in the same or opposing direction in some engines, never assume that is the standard configuration for a particular engine; they can be all different, depending on what the engine engineers wanted to accomplish. The 'Top's and dots face up.

2M694 is a Hastings part number. 40787 is a Perfect Circle/Mahle number. So I suspect that this is an overseas set and they put on both numbers for the American market. (Google 'Hastings 2M694' or 'Mahle 40787'.)

The 'M' in the Hastings PN is for Moly faced top ring, and the Mahle PN is for premium rings (usually indicating a Moly faced top ring) What is bothering me is that I have never gotten a Moly faced top ring set where the Moly facing was not obvious on the top ring; it is always a silvery-grey color. I see that on neither ring here. But I don't know everything so I'd go back to the shop and ask about this; I don't think you actually have Moly faced top rings.

Do you have a ring installer? It will help you to keep the top 2 rings straighter in installation.
Note that the chamfers are quite different. I would assume for this engine to have a chamfered ring in the 2nd groove. (Ooops there I go assuming! Not good!)

nm9stheham said
More Info: Here is a link to the Mahle catalog:
MAHLE Aftermarket North America | Piston Ring Catalogs

You can find the detailed ring set description on page 328. It lists the individual ring profiles, and you can refer back to the early pages in the catalog to see the profiles. I cannot find the top ring profile that matches either that you show (RF-10YF); one of your rings does look close to the ring profile shown for the 2nd ring (BT-10).

I'd surely go back to the shop and at this point. Actually, for me, I would be thinking of getting the $$ back if I could, and even if I couldn't, just get a known ring set.

P.J.H. said
Rings are manufactured by ertel, owned by hastings. they SHOULD be made in Canada. Nothing wrong with that set, as long as you install the rings with the pip marks up and the top ring in the top groove with the letters "top" up. The OP just wants piece of mind, so I suggested he double check with the machine shop. It's not that complicated.I shouldn't have even mentioned reverse torsional rings, it only muddied the waters, but he wanted to know if the bevel faces the opposite direction in the second groove. It doesn't in this ring pack.