General Tech Grant Piston Rings--Can't Fit Them

[KVH]

Is there a trick or method to installing the oil ring and two retainers? I'm having a real problem. Four tries and they don't go on correctly. I'm carefully watching to avoid overlap of the red and green tabs, and I've watched "Youtubes" that make it all look so easy. In addition, I've done this before myself. But this time no luck. I can't pinpoint the problem, other than to say that the retainer rings don't snap into place and the oil scraper ring looks offset or otherwise just not seated. Any suggestions appreciated. My pistons are County 87mm, and the Grant rings are 86mm oversized per the box label listing G1173.040 which, according to everything I find, means oversized 1mm to 87mm. Thanks all.

 

[NutmegCT]

Sounds like you may have a faulty batch, or mis-matched set, of hardware there. Give a call or email to your supplier, and/or the manufacturer, and share the details. Then let us know what you learn.
Thanks.
Tom M.

 

[CJD]

Make sure the waffled oil ring slides easily into the groove and will go all the way to the bottom of the groove without binding. If it binds there is a manufacturing problem. if you have watched u-tube videos, I doubt I can add much else...it is fiddly.

 

[sp53]

Well I am kinda where you are at but have no advice that would help. I was wondering how you put the order together. When you got the Grant rings, how did you explain the County piston size? Are rings for a 3 ring 87 mm piston all about the same thickness?

 

[Sarastro]

The set I bought had Grant rings and County pistons and liners. Sold by Rimmer. There is nothing unusual about that combination, and it should work. The only problem I remember was making sure that the ends of the oil ring didn't slip and overlap when I installed the piston.

It's hard to say more without seeing the parts. It seems possible that there is a manufacturing error, but you should be able to measure the gap and the rings and determine if there is a dimensional problem.

 

[TomMull]

I overlapped one the first time I used the 3 piece ones. I've hated them ever since.

Tom

 

[KVH]

I finally have all four Grant oil rings installed. The procedure would have been easier had I earlier decided to secure all pistons (with attached connecting rods) stationary in a padded vice.

I think part of my problem was needing “too many hands“ to hold the piston and maneuver the retaining rings around the oil ring while avoiding hop and overlap.

Regardless, this was a rather tedious process, with with two of the rings several times “hopping“ and overlapping the red/green.

I remember being spoiled by Hastings rings that I used on one of my other cars with such great ease.

However, for the record, these Grant rings appear proper and can be installed correctly with attention and reasonable skill, and maybe even with some ease when the piston is secured in place.

 

[Sarastro]

I used Hastings rings on the second engine I built, and there was a world of difference. I'll use them instead of the Grants from now on.

 

[KVH]

Yes and just a note—I searched and neither Moss nor BPNW had them in stock for 87mm. Same for TRF. I then checked Hastings and found a listing but no indication they were in stock. I sent an email to Hastings inquiring and got no response.

Maybe I missed something-I think I’ll try calling tomorrow out of curiosity.

I worry as we get older that fewer parts outlets will be around. I think we’re already noticing some service changes and other things after VB got swallowed. When I bought my first 4A in 2004 and Harry Hanks and Blaine Graham were around, and the showroom in Goleta was open I remember thinking the world was just great.

 

[KVH]

Well I am kinda where you are at but have no advice that would help. I was wondering how you put the order together. When you got the Grant rings, how did you explain the County piston size? Are rings for a 3 ring 87 mm piston all about the same thickness?

This is way late. Sorry. Not sure you got an answer here. My County pistons are 87 mm. I verified and all is correct there. The Grant rings were in a box labeled G1173 040, and the 040 is the extra mm from standard 86 mm pistons. The rings are 3 per piston, and the upper two compression rings are identical. The oil scraper ring is thicker and held in place by two additional retainer rings, one above and one below. My set came with "zero" instructions. The Grant website has scant instruction. To install the oil ring properly care must be taken not only to avoid "overlap," by to keep the retainers from distorting or catching along the chamfered edge of the piston groove--it happens and is frustrating. I'm not the only one here who has installed Grant rings later to find that "something" in the installation process allowed the ends to overlap--red over green or vice versa. Others say they've had no issue with Grant rings.

I'd be interested in your experience and anything you've learned along the way. Grant is a good company, has been around a long time, and is a primary supplier to our cars.

 

[poolboy]

This is how Hap Waldrop, a man in the business (Acme Speed Shop) of building engines handled Grant rings

I always love taking these photos, TR6 engine rebuild (Page 2) : TR6 Tech Forum : The Triumph Experience

Let the assembly start Hap Waldrop Acme Speed Shop 864-370-3000 www.acmespeedshop.com

www.triumphexp.com

 

[TomMull]

Hap's write up certainly changes my mind.

 

[CJD]

I have never had any trouble installing oil rings. I can't say what I do that makes it easy, but I can say this:

I always push the wavy ring in first. I then offset the upper and lower rings to the wavy ring, so each is 1/3 of a turn opposite from the next break. I push the wavy ring fully in the slot on the side I start one of the steel scrapers. Since the scrapers are thin steel, there is no fear of them breaking, so I give them a good bit of twist as they go in.

Once in every few, the wavy ring ends will overlap as the first scraper goes in. I just pull out the scraper and do it again. I think the key is to make sure the wavy ring is fully in the slot in the section you are working on. That allows the scraper to easily seat on it's ledges in the wavy ring. As you spiral in the steel ring, you press the wavy ring in as you work around the piston. When you get the first scraper in, the second goes in easily, as the first scraper holds the wavy ring fully in the slot.

 

[poolboy]

I didn't have a problem putting them on the piston, but somewhere between the ring compressor and the installation in the block there was overlapping and high enough oil consumption to investigate...Found a couple overlaps.

 

[KVH]

I have an update, and two questions. The update, as I alluded to earlier, is that in 2015 the rings recommended for the TR4 oversized 87mm piston set, are the rings specifically for 87mm (Moss 817-200), and not the prior "pairing" which was 86mm oversized by .040, which generally equates to 87mm. I cannot explain why, but both sets of rings are offered, yet at different prices, but they differ--and that brings me to the questions:

a) First, the oil ring on the true 87mm fits much tighter and without the play that had disturbed me in the 86+.040 set. Before being compressed, however, the protrusion beyond the skirt is only about 1/32 of an inch. I guess that's what I'll live with and hope it works, but does that concern anyone? My assumption is that the degree of protrusion is not that relevant so long as the force of compression and pressure against the sleeve is the same, which, hopefully, it is; and

b) The top two compression rings of the straight 87mm set are definitely looser and sloppier than the 86 +.040 set. The uncompressed ring gap is also bigger. Again, I'm going to proceed under the assumption that the compressed state is all that matters. I've checked the compressed ring gaps and they're right about spec at .010, though maybe on the .009 side. Therefore, I think I can ignore the looser initial fit when compared to the prior recommended 86+.040 set.

Technical, I know, but I'd really appreciate any thoughts. thx

 

[TomMull]

I've no particular expertise but logic would tell me that if either of your choices are within specifications, and they seem to be, they are good to go.
Tom