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Check balls

Pretty much anything not covered by the topics above. Short lived production bikes or vehicles, Electrical, Tires, Paint, Brakes, etc. Use this for tech questions, and "Shoot the Bull" for general conversation, no tech.

Moderators: Curt!, Pa

Post Thu Feb 01, 2001 2:07 am

Posts: 108
Location: San Diego
Cotten! Assuming that the check ball is nowhere near a "tight" fit in the passage (so that it otherwise becomes the flow restriction), and that the hole was the same size, and that ball lift off the seat was the same, the smaller ball would pass more oil!

On the other hand, you are also right that a larger orifice [and all other things being equal](and therefore the perimeter of orifice is longer) will pass more oil.

The differences are too small here to generalize too far, I'm afraid.

[This message has been edited by Guy Winton III (edited 01 February 2001).]

Post Thu Feb 01, 2001 4:15 am

Posts: 3010
Location: Central Illinois, USA
Now I understand.
...It's the same difference.

Post Thu Feb 01, 2001 9:42 pm

Posts: 108
Location: San Diego
OK, Cotten, the answer wasn't too clear. How much oil passes between the ball and seat is a function of the space between the 2! (duh, Guy)

I was trying to say a smaller ball will create a larger opening between it & the seat than will a larger ball (all things being equal).

And a larger ball AND larger seat will pass more oil than a smaller ball and seat (all other things being equal).

But, the small differences between the ball dimensions quoted make it hard to SWAG the result (I mean, doesn't the smaller ball actually seat inside of where the larger ball would on a given seat?)

And, this all assumes that the ball & seat area are the only major restrictions on flow (ie the oil can get by the ball OK).

Is this any better??

PS: I'm sure those V8s also benefitted from the lesser oil pumping pressure by better timing as a result of less cam windup, plus the "free" HP effect.

[This message has been edited by Guy Winton III (edited 01 February 2001).]

Post Fri Feb 02, 2001 6:25 am

Posts: 3010
Location: Central Illinois, USA
Whoa,now,..we are mixing our confusions!

This started out talking about ball checks, and the sump check and the pressure bypass check are two different animals.

(The teflon experiment was just for the sump problem, and it was just a bandaid. Couldn't ya tell I wuz joking?)( I better learn to type emoticons 8^# )

Hoot's concern was for the bypass (I presume.) There, the ball (or later a pistonlike thang) merely gets pushed back (as Rene pointed out)to open a side passage.

The restriction is the passage, not the clearance around the ball.

If the checks were a restriction that was significant, we would all have removed them long ago. And probably smoked up a storm.

Post Fri Feb 02, 2001 2:50 pm

Posts: 3010
Location: Central Illinois, USA
While we are inside of our pumps,..
What's that little baffleplate for inside of my OHV bodies?
Just a bubble buster?

Post Sat Feb 03, 2001 3:04 am

Posts: 3010
Location: Central Illinois, USA
It's underneath the welch plug on the top. I have a j-peg, but I can't always get Sparkplug's site to work for me. I'll try again when I have some chinscratching time.

Post Sat Feb 03, 2001 2:17 pm

Posts: 3010
Location: Central Illinois, USA
If you aren't anal retentive and paranoid when you blast a body,.. or perhaps the welchplug leaks,.. you may never realize its there. My knucks have them, and I'll have to inspect a '53,'60 and a '65 I have on the bench right now.(Not too many pans are in, with all of the Indians circling me.)
These things are T-shaped with two large holes in the wide bottom leg of the T. And they seem to just swing loose from the top. You can just make out the edge of them through the gallery hole.

Post Tue Feb 06, 2001 12:38 pm

Posts: 3010
Location: Central Illinois, USA
Uh oh.
I guess this means that I can't just pitch the machined valves in the '53 I am doing.

I burnished it's sumpcheck seat for a comon ball 10,000 miles ago and cleaned up it's act while sitting quite well. Now I am into a total overhaul on it, and the ball part of the bypass valve (wotta joke) is worn.

Since 25/64" balls are not readily available, I must decide whether to burnish for a 3/8" ball, or just throw the machined valve back in. I cannot see where a little bleed past the bypass could be significant anyway.


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