On Wed, 12 May 2010 10:00:08 -0500, "Karl Townsend"
wrote:

I'm repairing the same issue on my airblast sprayer for about the fifth
time. Own something long enough and the same problems keep repeating. the
sprayer has a vibration in it at 2500 tractor RPM, 540 PTO RPM. The
vibration is not like a tire out of balance but its a bucking forward to
reverse. When it gets a little lose, in a few more hours of run it will damn
near shake the tractor off the ground. Its also a natural harmonic at this
RPM, slow down and the vibration goes away. Unfortunately, this REALLY
reduces sprayer performance.

I'm replacing the entire PTO shaft and tightening up the clearance in the
gear box again. if everything is tight, the problem is less severe. The is
working on the symptom, not the cause.

This is a long shot, anybody know about balancing this sort of vibration or
changing the natural harmonic frequency?

Karl


I'll take a stab at this one. This is a insecticide sprayer, right? If
so, that kind of stuff is awfully hard on equipment. It eats at metal
and is sticky. Is the fan clean? Could it be nasties built up in the
clutch, maybe when on down time leaking in the same position.
Bad bearings, that would do it. Sucking air between the tank and pump?

Just someone tring to help that klnows what a
Malathion-Methyl-Parathion-Ketone Flop is.

SW