Rings

[Gyrhead]

Hey guys, been on vacation and came home to find my new rings dropped by UPS into the wife's flower pot.. mushed the Impatients. Just can't get great quality service these days....

Just before I install them, a couple of points/questions as the Ford shop manual is confusing me AGAIN....

Arrows on pistons face forward, Right? Pretty sure I remember this, but just checking...

Oil control expander gap points to arrow and segment ring gaps go 1" left and right from that? Book seems to suggest that expander gaps go in the rear, but diagram shows them aimed at the arrow.

2nd and 1st ring are 180 degrees off from each other, but not in skirt area?

Do I have all this right?

[Gyrhead]

bummmmpppp.

[MikeFleming]

When I have more time, I will give my $0.025 worth of comments. Be patient.

[Gyrhead]

When I have more time, I will give my $0.025 worth of comments. Be patient.

Fleming, You know the suspense is just killing me. I got a bad rod bearing in the batch, so nothing's moving yet anyhoo. I was starting to feel like a TB patient

[MikeFleming]

I was hoping I had some pictures of pistons and rings and aligning them - but no luck. I did find some showing end-gap filing and measurement.

So where to begin?

Let's start with checking the rings fit the pistons. Decide which specific rings go to which piston (and which piston goes to which bore) and find a way to label them. i use a black marker and tag the top of each ring end with marks indicating which bore (cyl 1 = 1 hash mark). Once we know this we can check the side play and depth to the top two rings.

Note that if there is any step or taper on the INSIDE of the ring, that side goes up - towards the combustion chamber. Otherwise there is always some marking on the rings that means UP. Roll the top ring around inside the top ring groove to see if there are any tight spots. The spec is about 1/2 thousands of an inch of clearance between the groove and ring side. If it's too tight, clean everything again. If it's too loose, determine if it's the piston or ring. Replace as needed. With the outside of the ring pushed fully into the groove, the inside should never protrude outside the piston side. Do this for the top two rings/grooves on each piston.

1168

Next measure the ring end gaps.

You need to insert each ring, individually, into it's matched cylinder without damaging any coating or the bores. It's easiest to push the ring itself into the bore about 1/2" with the ends facing up, then slowly rotate it to flat in the bore while holding the ends together. If it won't go in cause the ends butt together, then it's too large and needs filing.

11641165116611671163

Use a piston and rod assembly to push the ring down into the bore until the piston skirt just enters the bore - that should place the ring square in the bore. Oil rings scrapers should be 0.030" end gap. Top and second rings should be 0.015"-0.018", error on the larger side. If you plan to see upwards of 7500 RPM or make more than 100WHP per hole, then add 0.002-0.003" (0.018-0.021 total).

File them from the outside to the inside if you do not have a proper ring filer. The top rings have a plasma-sprayed moly coating that is VERY brittle and filing in the wrong direction can chip the coating. Some second rings have a chrome coating which can flake off also. Use a SHARP (aka new) file. After removing some material, carefully de-burr the edges and test the end gap again. Yep, tedious and time consuming but that's what engine building is all about. Do each oil ring set at a time and then move to the next bore. Then do the all the second rings, then all the top ones. Doesn't really make any difference other than you will learn how each ring type needs to be cut - and remember that for the remaining rings of the same type rather than having to re-learn all over again. It may take more than one day to do this the first time you attempt it.

Start with the oil ring pieces. Most oil rings these days are a three-piece unit with a wavy expander and two thin steel scrapers that are hard-chromed on the cylinder wall surface. Then the second ring is usually a simple ring with the top one perhaps being a tapered one, a dykes style (not the LGBH style of dyke) or just a plain normal ring with a moly coating. Note that if there is any step or taper on the INSIDE of the ring, that side goes up - towards the combustion chamber. Otherwise there is always some marking on the tings that means UP. There is usually no fitting required for the oil ring expander.

1169

Once the ring testing and fitting is done and everything has been scrupulously cleaned, we are ready for final assy. And that's a different chapter.

Read up on the spiral method of ring installation onto pistons (versus just expanding the rings) to install them (this requires twisting the ring) . Also read what is recommended by the specific ring manufacturer you're using. They all like it different.

Where to place ring gaps? For the three-piece oil rings stagger the three gaps about 1/4 - 1/3 the way around the piston. Try (this is difficult) to NOT have any end gap on a direct piston skirt side - where the thrust area will be. That means move the gaps more towards where the pin axis is. Most important is to not have a scraper end near the expander end. They will fight.

Install the oil ring expander first. Then install the bottom scraper via the twist method - making sure it engages each of the little tabs on the bottom of the expander. Install the first one clockwise. Then install the top scraper from the other direction (counterclockwise in British). Again, making sure it engages the expander tabs. Once the three pieces are installed, the oil ring assembly should rotate as one object in the groove.

Then place the top two rings end gaps 180 degrees apart, and try to not have them perfectly lined up with the oil ring scraper ends (don't care about the expander). And don't worry about it too much. The gap represents about 0.16% of the surface area which ain't very much.

1170

Lightly oil the bores with engine oil & smear a few drops of engine oil onto the piston skirts. Using your favorite ring compressor and assortment of hammers, rod bolt covers and wooden blocks, install the pistons/rings/compressor assembly with the rings dry. Push it down to the crank, install bearings, cap, nuts (or bolts). Optionally tighten the rod bolts at this point. If you do not do it now, DO NOT forget to do it later. Really bad things will happen really fast if you forget even one fastener. Lather, rinse, repeat for the next cylinder.

[Bob Holmes]

Let me suggest that you do tighten the rod bolts and rotate the crank. That way you'll know if you have any bind introduced into the assembly. It will save you from having to backtrack to find the problem.

And you probably already know that there is a correct and incorrect way to orient the pistons, and rod caps. Keep everything in order.

[Gyrhead]

Mike, I knew I could count on you. Thanks for an excellent and comprehensive write-up.

One question I still have after studying your material is my top and middle rings are both marked (Sealed Power) with a small dot stamped approximately 3mm from the end of one end, however orienting this dot upright on the oil control ring (middle ring) will result in the internal taper or shelf being pointed down, whereas the compression or top ring's dot pointed upward will result in the taper being pointed up. What am missing? Should the dot's presence and orientation rule or should I rely on the taper? The instructions, which are in 14 languages including Greek and Farsi - all imprinted on a tri-fold 4x4 plastic bag - state "If the ring is marked, position the mark upwards. If not, position the taper upwards". What gives?

Mike, what pistons are those?

[MikeFleming]

Ahh, quick answer. More later.

The taper on the top ring is a normal "push outwards and downwards" ring type. The second ring is a "reverse twist taper type" ring. Both go with the dot mark on top. The second ring is designed to twist in the slot when it gets lots of pressure. Someday we will have a long discussion over beers, complete with white board diagrams, on how gas pressure rings work. Until then, just install them with the marks up as the instructions show.

I didn't know you read Farsi. I dated a gorgeous Iranian girl a few decades back and had to learn some Farsi. High-maintenance and high-tempered and English was not her first language. She hated Iraqies, btw, and refused to speak to them in Arabic (which she was fluent in). She worked as a translator for the courthouse. That was a long time ago - another beer story.

[MikeFleming]

The pistons are from Race Engineering. Specs on that engine build are below.

- Strapped/studded 2.3L turbo block
- Lightened 2.5 crank
- 5.5 Crower rods
- Short dished pistons from Race Engineering with 0.047" (1.2mm) top ring (moly), 1/16 (iron), and 3/16 3-piece oil ring; 0.927 pins; +0.030". three lap SpiroLocs
- 8.5:1 static CR
- Cometic MLS head gasket
- Essy d-port alum head with smoothing & porting (231/197)
- Essy 2277 cam
- Rod's header with some serious porting
- Charlie's T3/4 thingie with a stage 3 0.63 A/R turbine side; compressor wheel is rated at 55 Lb/min inside machined stock SVO compressor housing; currently set to ~ 15 PSIG (managed by the EEC) during tuning (flows about 44 Lbs/min according to 70MM MAF)
- 3" exhaust all the way including CAT (with a 3.5" really spiffy looking chrome tip)
- Round tooth belt with aluminum thingies
- 60mm throttle body
- Custom charge cooler installation
- Aluminum water pump
- 95A 3G from PA Performance to charge a very small battery
- Lots of ARP stuff
- Hand fitted, assembled and installed by some guy named Fleming

[Gyrhead]

I didn't know you read Farsi. I dated a gorgeous Iranian girl a few decades back and had to learn some Farsi. High-maintenance and high-tempered and English was not her first language. She hated Iraqies, btw, and refused to speak to them in Arabic (which she was fluent in). She worked as a translator for the courthouse. That was a long time ago - another beer story.

I actually don't read it, but was able to recognize it. I think the written form is actually called Persian. I have a friend who is Turkish who told me a little. Yes, those Persian women are fiery. I went to high school with a couple of close adolescent female relatives of the Former Shah of Iran Mohammad Reza Pahlavi (after being deposed). I love stories, I also love beer. BTW, I love SVOs too.

[MikeFleming]

I love stories, I also love beer. BTW, I love SVOs. And I love all things red too. Fixed.

[Pat]

Mete-Leve was the original ring vendor. I think that CP bought them out a couple decades ago.

[ChrisCurtin]

Any chance you'd do a similar thread on installing the crank :)? Especially setting the thrust bearing? Short block will be my winter project (assuming ANOTHER one of my kids doesn't need wisdom teeth pulled. Last winter's budget went for those. ) and what I've found in manuals, online etc. still doesn't totally make sense.

Thanks,

Chris

[Gyrhead]

I just set my new crank up and took a bunch of pictures, however Mr. Fleming likely has an insanely detailed file on this even though his motor was strapped.;)

[ChrisCurtin]

Hi Mike,

Thanks for the write-up. Question though: in the oil separator pictures one shows the gap pointing up, the other down (both are circled in the pictures) Does it matter which way it is installed?

Thanks,

Chris

[MikeFleming]

Question though: in the oil separator pictures one shows the gap pointing up, the other down (both are circled in the pictures) Does it matter which way it is installed? Chris,

Does not matter up or down. What is critical is the expander gaps are butted together - in direct contact with each end. Otherwise it may not fit down into the groove.

[MikeFleming]

Any chance you'd do a similar thread on installing the crank :)?

however Mr. Fleming likely has an insanely detailed file on this even though his motor was strapped. Looks like I missed this request. My bad.

Don't know if I have enough pics of setting the thrust bearing, I'll have to look.

I'm also planning on adding a Project thread for the engine build, the chassis preparation (including the addition of the internal Jungle Gym for hte kids) and the painting and re-assembly processes.

Gonna be a couple weeks before I'll have the time to start on these though. Got seminars all next week and a few track events in January with associated car prepping. Then I'm removing the calipers on the EVO for power-coating. The world needs more red.

[ChrisCurtin]

Chris,

Does not matter up or down. What is critical is the expander gaps are butted together - in direct contact with each end. Otherwise it may not fit down into the groove.

Thanks Mike.

[Raven855]

Excellent write up Mike! A good read and some good info.


I dated a gorgeous Iranian girl a few decades back and had to learn some Farsi. High-maintenance and high-tempered and English was not her first language. She hated Iraqies, btw, and refused to speak to them in Arabic (which she was fluent in). She worked as a translator for the courthouse. That was a long time ago - another beer story.
I will call you to task on this tidbit that you posted though. You know the rules, if you don't post pics it didn't happen!

[MikeFleming]

I will call you to task on this tidbit that you posted though. You know the rules, if you don't post pics it didn't happen! Sorry but photographic evidence of my activities in the 70's is beyond the scope of this forum (although I do have some pics of cars I played with in that era, but not nearly enough - I have pics of Pat from ~1980 at WSR though).

That's like asking you to post pics of you with each of your high school teachers.