KIPS Valve

[stringburner]

I'm still confused on this. When the engine is off, and you turn it by hand, should a properly operating KIPS snap back on it's own from the open position, or would it go open, stay put, then you have to roll it back to the closed position? I was thinking it was the latter from what I've read, but someone told me otherwise. Just wondering if mine is whacked or not...

[KDXer]

Don't worry about me I deleted my post, I thought you meant turn the engine over by hand, not the KIPS.

When the engine is off, and you turn it by hand

[Indawoods]

If you turn the KIPS shaft by hand... it will not "snap" back... but will usually slowly return to about 3/4 of the way. This is normal.

[KarlP]

Inda-
Are we sure?
My recently cleaned KIPS doesn't "snap" closed, but it does close pretty quick, and all the way.
My detent ball and spring are out for now and I'm operating the KIPS through the left hand round cover with a 10 mm socket driver.

[Indawoods]

A clean one will... but just checking the KIPS midway through a season or without a recent cleaning... it tends to be carboned up a bit...not to mention spoo holding it back a bit.

[stringburner]

If I recall: On mine, with:

1)The right side kips cover off.

2)The claw gear that is on the end of the rod going down to the clutch side loosened and out of play (removed or turned so it doesn't contact the gear in the rh side behind the cover).

3)And viewing from the left side hole (the one you take off w/ a big ole' screwdriver).

It turns freely open and closed by turning the gear from the right side, but it doesn't return to any previous position on its own. That sound like it's operating properly? Or do I need to test it differently, like running, and/or w/ the actuating rod in place?

[Indawoods]

The Rod has to be in place... what else is there to return it?

[Jeb]

Hey, stringburner!

There's two springs that makes the KIPS work.

The spring in the crank that activates the KIPs via the govenor rod - the rod with the claw at the top - gives you the "snapback". Under operation and enough RPMs there's enough centripetal force created to overcome the spring tension of THAT spring to compress it and push the govenor lever (a knob on the bottom end of the govenor rod). This twists the govenor rod. If you were to turn that rod right now - carefully - you'd feel the tension, and when you let go it should return.

At the same time this spring in the crankcase is being compressed, the "claw" you've loosened and moved out of the way is turning one end of the rod whose other end has the other spring (this spring is in the "left side hole the one you take off w/ a big ole' screwdriver"). This spring provides additional tension, working against the ball detent.

Without the claw attached, once you spin that rod you're trying to spin enough to pop the ball out of the detent, there's nothing to snap back.

It's a piece of work, the KIPs . . .

[Jeb]

So . . . the spring in the crankcase moves the pieces, and the spring on the actuator rod (or whatever it's called) holds things firm so that the KIPS "snaps" into action. If the actuator rod spring were removed the KIPS opening would be more gradual.

[stringburner]

I kinda was thinking the rest of the parts I took out of the equation had something to do w/ the "snapback", but I thought I read in the manual or someplace else, not to manipulate it w/o first detaching the claw actuator from the gear.

Thanks for the replies fellas.

[canyncarvr]

So...everything is peachy?

IF you were by way of hamfisted action manipulate the KIPS without detaching the claw you would in effect be reefing on the LHT nut atop the claw without supporting the actuating rod.

That breaks things.

Nothing wrong with activating the KIPS via the nut under the LH slotted cover...just don't reef on it.
Re: 'If the actuator rod spring were removed the KIPS opening would be more gradual.

I wouldn't say more gradual, but the start of the KIPS movement would be sooner. Fredette use to either (I don't recall for sure which) remove that spring or put less tension on it by way of 'preload' on the spring (washers on the spring retainer bolt). Last I heard he quit doing that because he was of the opinion it didn't accomplish anything.

'Snap' back? No. 'Move' back? Yes. With the engine running it should move back to rest when the revs are down.

As you mentioned, you can check that movement via the LH cap when the engine is running.

Any failure to return to 'rest' when the rpm's are below activation-time will subtract from bottom-end performance.