Ring gap position?

oldmanolds · February 01, 2007, 11:09:29 AM

I'm rebuilding an Olds 350 and the question came up of ring gap position when sticking the pistons.Does it really matter as long as the ring gaps are not in a line?(or posistioned in a line together.)

Charlie Chops 1940 · February 01, 2007, 11:50:06 AM

I go around the piston by thirds. Also the 3 part ring needs the ends staggered too. Put a few squirts of your favorite oil on them.

Charlie

enjenjo · February 01, 2007, 01:22:39 PM

I do the same as Charlie. Seems to work for me.

oldmanolds · February 01, 2007, 02:02:52 PM

You know that makes me feel a little less stupid.This my first gas engine build up and I read that they(rings) all have set posistions on the piston. Thats from the Chilton manual.On a diesel build up I always went in thirds around the piston.Thanks. oldmanolds

SKR8PN · February 01, 2007, 07:58:43 PM

I do like those two guys, BUT.....I use DextronII tranny fluid on the rings before I set them in the bore.

enjenjo · February 01, 2007, 08:06:09 PM

I use Dextron too. I have for many years.

slocrow · February 02, 2007, 04:03:00 PM

I agree with the info provided so far but if I remember correctly, there was another theory about gap placement, back in the day. It had to do with V8's and their piston angle. I believe you were instructed to keep all gaps above the piston horizontal center line. You know, like the top ring around 12 o'clock position, middle at 2 and the oil rings scattered between 9 & 3 just not together. This was based on 12 o'clock being towards the intake, naturally.
The thinking was that the weight of the piston would help close the gap.
I have no idea if it works or made sense but I did a few that way and never noticed any negative results.....................Frank

Dave · February 02, 2007, 04:31:52 PM

Quote from: "slocrow"I agree with the info provided so far but if I remember correctly, there was another theory about gap placement, back in the day. It had to do with V8's and their piston angle. I believe you were instructed to keep all gaps above the piston horizontal center line. You know, like the top ring around 12 o'clock position, middle at 2 and the oil rings scattered between 9 & 3 just not together. This was based on 12 o'clock being towards the intake, naturally.
The thinking was that the weight of the piston would help close the gap.
I have no idea if it works or made sense but I did a few that way and never noticed any negative results.....................Frank

This is good comming from a guy that dont even set his own wheel bearings

Ill bet when they tell you they need packing you tske em out and stick em a box dont ya

.. I never heard that theory on the rings and i always used a good quality motor oil.
Dave

Sean · February 02, 2007, 05:25:19 PM

Quote from: "SKR8PN"I do like those two guys, BUT.....I use DextronII tranny fluid on the rings before I set them in the bore.

I do the rings in thirds too, but I always smear STP on the rings. An old mechanic I worked for when I was a kid taught me to do that. His theory was that the STP would stay in the rings longer if the engine wasn't going to be used immediately.

If he was building an engine that was going to be installed and fired within a few days, he used STP on all the bearings too. But if he was building one to keep in stock for an unknown length of time, he used white lithium grease for assembly lube.

EMSjunkie · February 03, 2007, 08:00:02 PM

I have always used motor oil too.
White Lithium grease on all the bearings, lifters, cam, rockers.

use Lanolin on my hands, keeps 'em soft.
Lanolin comes from Sheeps wool :oops:

Vance

tomslik · February 04, 2007, 09:57:22 AM

all this "lube" talk got me to thinkin'......

oh, anyway, lately i've been hearing not to put anything at all on the rings/bores.
i seldom build engines anymore so take that for what it's worth....

kb426 · February 04, 2007, 10:09:03 AM

Bear in mind that most of my engine exp. is blown racing types. I wiped a circle of oil around the top of the cylinder and shoved in the piston and rings with almost no lube. The oil ring pushes the oil down the cylinder as the engine is turned over during assembly. I wanted minimal amounts of oil to attract dirt in the pits and also want the rings to seal instantly. The rule of thumb with a blown engine was that if the rings didn't seat during the first burnout that your cylinder prep was wrong. Also when the engine first starts and has oil pressure, I reved it up. The reasoning being that the only thing that oils the cylinders is the spray from the rods. If I was assembling a street engine, I would put lube on the rings before installing. My exp. has been that any oil works. With modern cyl. prep and ring configurations, ring sealing shouldn't be a problem.

model a vette · February 05, 2007, 04:58:09 PM

I was told, by the machine shop that machined my last engine, not to use white grease because it doesn't mix with the oil after startup. He said it got stuck in places because it had such a high melting point.
Any opinions?

kb426 · February 05, 2007, 06:39:18 PM

I've used white grease on bearings for years. On my street motors, I never had to take them apart so as far as I know, there isn't a problem. This is lubriplate 105. I think there are better lubes available now then 40 years ago. If you are concerned, mix the white grease with oil and see if the white grease dissolves after stirring.

enjenjo · February 05, 2007, 06:49:54 PM

Quote from: "model a vette"I was told, by the machine shop that machined my last engine, not to use white grease because it doesn't mix with the oil after startup. He said it got stuck in places because it had such a high melting point.
Any opinions?

An old story. About 30 years ago, I was involved with campaigning a drag car with a big chevy in it. We built a fresh motor, dropped ir in the car, hooked everything up, and fired it. Ni oil pressure. With screwing around, it ran about 3 minutes before we discovered it. Shut it down, check the oil, and pulled it out, and back down. There was no damage to anything. New gaskets, and it went back together, FILLED with oil this time, and refired it. Finished the season with that motor, never had a problem. The owner of the car still has that engine today, of course it has been gone though a couple times since then.

The point of this is, it was assembled with Lubriplate 105 Assembly lube, with Dextron on the rings. Even the roller rockers had 105 on them. The oil pump was packed with it.

That was a testimonial that I can't ignore. We also used it on diesel trucks where I worked, and I saw more than one started with no oil.

Moly cam lube is much harder to dissolve in oil, and for that reason, after cam break in, I change the filter. Then at 500 miles, the oil and filter again.

Not to say I have not had failures, but lubrication was not involved in them