a1320honda

Im just wondering if rings make a 100% seal. Like a motor in excellent shape, if you were to put a thin liquid, like gas, in the cylinders with the piston all that way down, would it hold it for a long time or would it slowly seep past the rings and into the oil pan?

blinx9900

there is usually anywhere from 150-200psi (assuming my math is correct? CRxbar for na and bar+boostXcr for turbo??) on the piston during its compression stroke and none of that is supposed to get past the rings... i dont know about 100% but they seal pretty damn good.

atec

Aren`t the rings sealing when the combustion accour.
combustion are forcing the rings to seal by pressing them outwards to the cylinder wall.

I dont think any engine are 100% leak free. but about 98% can be dune.

a1320honda

Reason i ask is i was tryin to figure out if my rings are seating with about 100 miles on em, the head is warped so while it was off i dumped some oil in the cylinders and over 24 hours didnt lose any oil, but i used gasoline and after about an 2 hours all the gas had been drained into the pan. So after a ton of research ive found that this would be a normal result.

blinx9900

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by atec &raquo;</TD></TR><TR><TD CLASS="quote">Aren`t the rings sealing when the combustion accour</TD></TR></TABLE>

i hope the rings are sealing during all 4 strokes, if not:

during power stroke you would get flames in your crankcase not to mention lost energy
during compression air would leak out into your crankcase so you lose compression
during exhuast stroke it would leak into your crankcase and nasty up your oil
during intake it wont create engough vaccuum to suck in as much air as possible.

crappy example/explanation but its 329am here and im passing out...

blinx9900

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by a1320honda &raquo;</TD></TR><TR><TD CLASS="quote">Reason i ask is i was tryin to figure out if my rings are seating with about 100 miles on em, the head is warped so while it was off i dumped some oil in the cylinders and over 24 hours didnt lose any oil, but i used gasoline and after about an 2 hours all the gas had been drained into the pan. So after a ton of research ive found that this would be a normal result.</TD></TR></TABLE>

err... why not do a leak down, or CR test?

a1320honda

I didnt know anyone who had a leakdown tester, but did do a comression test and got 200 across the board with 100 miles on the bottom end. I was getting oil in the coolant and there was an oil leak from between the head and the block plus it was smoking. But that head has been on prolly like 5-6 different motors in the last 3 years and never resurfaced. So while the head was off i was checking the probable condidtion of the rings. I think im good to go. I pulled the head and found when i put gas in the runners in the head several of the valves were not sealing. so that head just needs a makeover.

atec

sorry I think that went out wrong from my side.
what I meant was that when combustion accour it force the rings to seal even under the high pressure.
but I see now that was a little OT.

blinx9900

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by atec &raquo;</TD></TR><TR><TD CLASS="quote">sorry I think that went out wrong from my side.
what I meant was that when combustion accour it force the rings to seal even under the high pressure.
but I see now that was a little OT. </TD></TR></TABLE>

all good, i know diesles do that, and thats why they go 500,000 miles before a tare down, im not sure about gasoline engines though... damn there is just so much out there to learn...

RC000E

Valves not seating doesn't explain oil burning and milky coolant....your issue is beyond that.

Another issue is rings have a gap, so that can't seal 100% on a cold motor with no cylinder pressure. The gap is in place so that as the motor reaches operating temp they create essentially a gapless seal. Cylinder pressure also goes behind the ring in order to push them outward and also aid in seal.

Pouring liquids into your cold cylinders, with the piston just sitting there isn't a way to judge much. Doing things the way you are doing them is pretty off.

HatchEh2

first of all... stop pouring gas in your motor... it will eat everything!
your valve seals, rings, etc.

bolt a head onto the block with no cams in it.
torque it down.
take your oil pan and (if applicable) your windage tray off.
take your spark plugs out.
get a LEAK DOWN TESTER, OR get a fitting that will fit in your spark plug threads, and pressurize the cylinder with air. if you have a leakdown tester, set it to about 100psi.
it will then tell you what percent of that 100psi is leaking out. for instance:
a healthy motor should be no more than 3-4%
i did a leakdown on my 1990 b16a that doesnt burn any oil, and the worst cylinder was 3%.

i did my gsr with itr pistons, and the BEST cylinder was 6% and the worst was 8%. i went through 2 quarts of oil with every tank of gas..

now when you get all that down and if you dont have a leakdown tester, put your ear near the intake and exhaust.
LISTEN.
if you hear hissing out the intake, its probably your valve seat.
the valve cover should be off.
pour some oil on the respective valve springs to see if you can find air bubble, then its your valve seals.
put your ears under the block, if its coming from your rings, youll hear it.
*NOTE: keep your fingers away from the rotating assembly when the cylinder is pressurized... at any second the crank can turn as a result from the piston getting pushed down by the pressure.

now you know how bad each cylinder is, and from listening, you know what you gotta change.

EDIT: wow... i just realized how old this thread is..