piston rings

[69tr]

I have the cam and crank installed. Also the rear seal and front sealing plate.

I started to put the rings on the pistons can't figure out which groove the compression rings go in. They are not marked so I don't know which goes in the top groove and which in the 2nd groove.

One set has a small bevel on the inside radius and the other has a groove or offset on the out side radius. They are the same thickness and width as per the book. I think the one with the offset goes in the 2nd groove with the offset down and the one with the bevel goes in the top with the bevel up.

The oil rings came with 8 scraper rings and 6 expander rings. I know that some of the older motors only had one scraper ring. I don't know if they sent 2 extra or I am 2 short. If I only use the one scraper ring does it go above or below the expander ring?

Sorry for all the basic questions and thanks for the help, Pete

 

[poolboy]

So you did get the cam in properly ? I must have missed your post to that effect.
If you don't mind, what was the problem ? How did you fix it ?
You kinda left us hanging....

 

[69tr]

The freeze plug behind the cam was pushed in too far. I knocked it out and will replace it now that the cam is installed. I should have posted what I found just to let you guys know that I can figure some things out.

Sometimes it is the simple things.

Any ideas about the rings?

 

[TR3driver]

I'd go back to the vendor, and insist on getting the instructions that should be packed with the rings.

On the oil rings, if you stack up one expander and one scraper, does it fit snugly in the piston groove? All the ones I have seen (with multipart oil rings) use two scrapers per cylinder, on either side of the expander.

Here's a PDF I found from Wiseco, which shows some of the 1st & 2nd ring configurations. (I had to zoom in, but it was fairly legible at 150%)
https://www.satanicmechanic.de/download/Wiseco%20Piston%20Rings%20Installation%20Sheet.PDF

 

[Brinkerhoff]

If you have the thin scraper rings they fit above and below the expander ring , two per piston with the gaps staggered. Always use a piston ring plier to install rings , as they spread the expanding stress to the whole ring. I think the top ring ( from what you've described ) has the outside step facing up. This is in case you still have a ridge on you cylinder , the ring won't break. Always fit each ring into the bore it will go to and check the gap per the shop manual. If anything you want it a little larger than spec. not smaller , use a good sharp file to correct the gap. Always stagger your ring gaps and lightly oil the piston and wrist pin before assembling with a ring compressor. You should check with the ring supplier on those compression rings though. Kevin

 

[Andrew Mace]

I'm curious: who made the rings?

 

[startech47]

Make sure you stagger the gaps properly.

 

[69tr]

They are Hastings rings. The instructions in the box explained which side of the ring faces up but does not explain which ring goes in which groove. Both sets of compression rings are identical in size. The only difference is that one has a small bevel on the inside radius and the other has a small step on the outside radius.

I don't know if I am short 4 wiper rings or have 2 too many.

I will call Moss again today and talk to them. I called them yesterday but was unavailable when they returned my call.

I did put one of the compression rings in the cylinder yesterday and measured the end gap. It seemed a little wide to me. It was about .020. The cylinders are .030 oversize and I ordered the proper rings. Is this too much?

 

[Brinkerhoff]

Look Hastings up on the net and call them . Nice people. They'll help.

 

[poolboy]

The rings didn't come separate little numbered envelopes ?

 

[Spridget64SC]

Look Hastings up on the internet. The catalog information on their site should answer your questions. IIRC, Hastings usually wraps their rings in paper wrappers color coded and labled for location on the piston. If you have a chromed ring set, then the top ring will be the chromed or chrome faced one. The catalog also shows most of the ring types with their orientations. Hastings doesn't usually put marks (divots, printing, etc.) on their rings, so you have to use the wrapper or catalog informaton.

WRT ring gaps, usually the ring gaps are stated with an amount per inch of bore. The catalog will give a recommendation. I usually go for 0.004" of gap per inch of bore. Oil control is not as critical. Use 0.025" minimum.

Large compression ring gaps should be avoided. This is usually caused by too much piston to bore clearance. Have this measured at the machine shop and if you have a good bit more (like double) than the factory stated limit, then you should consider the appropriate replacement path. If you are just over the limit, then you might consider getting the next oversize and filing the ring down to tighten the gap. My experience with Hastings rings is that they fit a bore size matched to the piston size plus about 0.0025" fairly well. Anything more and the gap starts opening up quickly.

HTH
Mike Miller

 

[69tr]

The came in separate compartments of the box but were not marked.

 

[Spridget64SC]

Decided to go look at the Hastings site to check my memory. If you have ring set 6817, the top ring is a Type 102 torsional with the bevel facing up on the inside. The second ring is a Type 401 wiper with the OD notch facing down. Notch could also be considered a "Ridge-dodger"

If the 2C- set, then the Top ring changes to Type 362 which is a barrel faced triple chromed ring.

Also, I did find one ring type that Hastings marks with a divot. A Type 126 or 610 reverse torsional. Marked to prevent mixup with other torsionals more than likely.

Mike

 

[CJD]

.020 end gap sounds about right for a standard set of rings out of the box. They know that most mechanics don't check the end gap, and they want to make certain the gap will not close completely in the tightest anticipated bore size. If you want the tightest gap possible, then you have to order a "file to fit" set. If one is not available, the only other option is to order the next size up and grind/file to the gap you want. It's very time consuming. Mike gives a great discription. A street motor can take a smaller gap...if you race, the temps are higher, so you need a slightly larger gap.

In general:

bevels go up, whether on the inside or outside of the ring.
steps go down on the outside of the ring.
steps go up, if on the inside of the ring.

This won't help with which ring goes on top, but it looks like you have a handle on that.

John

 

[Spridget64SC]

After reading the posts in the thread over again, I think you have a "Broken set" of rings. I would agree that you are short 4 oil control scrapers.

You might want to try a 40 over ring to tighten up the ring gap. By my formula, 2.940+.030 = 2.970 and with 0.004/inch of bore, that comes out to be a nominal 0.012" clearance. You could go 0.014 or 0.016", but I wouldn't go much more than that on the top ring for street purposes.

Mike

 

[69tr]

I found the instructions on which ring goes in which groove. I was printed on the outside of the flap on the box. When I opened the box I turned the flaps back and did not see the instructions. (did I mention that I have senior days?)

I do have the 6817-030 set. and they go exactly as Mike said.

I am still 4 wiper rings short. I am going to call Moss later.

Thanks again for the help, Pete