Mark Landoll Harmonic Dampener question

[Smilin' Jack]

Pierre,
Lucky you got that corrected.....

I see Larry came down with his damaged 9A... such a shame...to have a hanger door come down on the wing...

He like the RV4 with the UL.

Hope your doing well
Jack

[Dmadd]

Had Landoll on O-320 RV-4 with MT fixed pitch. The prop was very light. Landoll ring smoothed out power pulses, and made it idle smoother. Previously, I could feel every cylinder fire... I didn't figure that was good for the mount either...
I'd do it again...

DM

Originally Posted by Richard Suffoletto

I have a 7A with a Performance wood prop and a Landoll Dampener. My plane came in at 1067 w/o paint and interior. I flew 20 hrs w/o the damper and the prop / engine combo was smooth running. The only changes I saw when I put the damper on was the ability to idle at 650 RPM vs 700, smoother idle, and the prop does not "slam" to a stop on shut down. I haven't noticed much difference in cruise...

I weigh 265 and with a friend who is 220 the extra weight in front does help the CG loading when baggage is carried. I set my gross at 1900 since I have fat friends...

Are the changes worth the money? Probably not....

[CATPart]

But is there proof (not just theory) that the Landoll does anything extra special to smooth out the power pulses, compared to a solid ring of similar mass?

My o-320 wood propped RV-4 was originally built with a Landoll. The builder eventually removed it in favor of a solid 12 pound inertia ring. He perceived no difference, so stuck with the more simple solid ring.

[Dmadd]

Mine was the solid ring. He had both available, and my understanding (from Mr Landoll) was wood props only needed the low tech version. It just added a bit a mass to the prop arc, which smoothed it out. Without it, for example, the prop would stop instantly when shut down. (not specifically WHY I used it, but an indicator of how it reacted)
I installed it because I didn't like the "bang bang bang" of the power pulses at idle... Even in the pattern at idle it did it. (MT prop weighed almost nothing) Metal props would NOT have this issue...
It did not slow down engine acceleration or deceleration at all. (very fast response with light prop)
The hollow ring, with the material inside it, was for prop balance issues as well as the harmonic component.
I liked the product. It did exactly what he said it would.

Hope this helps...

[Sdemeyer]

Originally Posted by Wally

Would like to communicate with anyone who is or has used a Landoll Harmonic Dampener. Post, PM or phone.

Thanks.

I installed one on my mustang ii not too long ago strictly for w&b reasons. It weighs 11 pounds and bolts to the flywheel. I did not notice any difference in vibration or smoothness but it allowed me to be able to carry baggage. The bolt heads are very close to the starter so if one ever comes loose, it's going to be a bad day for sure. Overall I am happy with it. My M2 has an o320 and sterba wood prop.

[Wally]

I also have a Catto 3 blade prop. Do you by any chance have instructions for installation? I know the dampener bolts to the ring gear but I also have a steel plate that seems to belong on the front of the dampener with the center against the ring gear. However, talked to Mark Landoll and he said it had something to do with the spinner. My guess is I wasn't communicating very clearly.

Wally

[MeAndMyToys]

Originally Posted by OneTwoSierra

No, my CG isn't bad. I just want to really load her up for OSH. With my 220 lb. wife and my 125 ib. self (just kidding, Pierre cracked me up.), we can carry a ton, but just not a ton in the baggage compartment. If I had more weight up front, I could get away with over 100 lbs in the baggage compartment that I might need going to OSH.

So just so no one misunderstands, I'm really thinking about trying this thing just to see what it's like -- I really don't have any particular issue I need to solve.

And, to answer an earlier post, some have claimed 75 to 100 more static RPMs with these things due to the smoothing of the engine and absorbtion of the pulses. I have no way of knowing if that's true or not yet.

Pretty sure Van's says not to go over 100 lbs in Baggage compartment regardless of CG. The baggage compartment floor is only designed for 100 lbs.

[Sdemeyer]

Originally Posted by Wally

I also have a Catto 3 blade prop. Do you by any chance have instructions for installation? I know the dampener bolts to the ring gear but I also have a steel plate that seems to belong on the front of the dampener with the center against the ring gear. However, talked to Mark Landoll and he said it had something to do with the spinner. My guess is I wasn't communicating very clearly.

Wally

I did not have any extra plates, just the ring and handful of bolts and nuts.

[Wally]

Interesting Scott! Not sure what I have!

Thanks for the responses.

Wally

[mike647m]

I have the harmonic balancer on an O-320 with Aymar-DeMuth wood prop. No extra plates, very smooth running, helps with 6 CG. Have about 60 hours, cannot compare, always had the balancer on.

Mike