RPM jumping at Full Power Checks?

[RudiGreyling]

Gents,

for the most portion of flight I have a stable RPM, with the exception of the full power take-off run 2650 RPM it jumps around a lot.

Standard 6 cylinder (IO-540) Lycoming with Mags, and SlickStart, 30K ohm resistor pickup on the P Lead.

I want to know about similiar experiences on same setup.

How have you solved it? Did you upgrade to the bigger resistor as discussed in the manual?

not keen to jump in behind the panel again 

 

[preid]

Rudi;
We have the same setup on the engine. Move up to a 100K ohm resistor. It will solve the issue.

Support;
My biggest issue is why does my RPM bounce and report over 2700rpm when I am decreasing power for landing and I am at 2400rpm? never does it any other time.
Thx

 

[lolachampcar]

100K IO-540 Slick Mags Still see some movement but much more stable now. Aircraft Spruce sells a VR pickup that mounts directly to the tach cable drive and MGL's hall effect sensor that screws into the Slick vent port. Both of these can replace the P-Lead pick up (I bought both for testing).