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Slow prop govening

Capt

Well Known Member
Hi guys/gals.

Just looking for ideas to what might be an issue with my Haetzell prop on my IO360, when cold it won't cycle at all @1800 RPM until the oil is close to operating temp. It's cold where I am now not freezing so takes a while to get the oil warm. If I take off before I get full pitch control the engine/prop over speeds up to 2900 RPM. Once the engine is at operating temp no issues, cycles first time and no overspending, during summer no issues either.
Engine/prop around 600 hrs.

Was thinking maybe sludge? Crank needs cleaning? Gov filter/gasket clogged?
Thoughts?
Thanks.
 
Could be the oil you are using. If not multiple viscosity, thicker oils are VERY thick when cold.
 
Sounds like normal operation to me. The oil has to be warmed up to flow properly, if your prop won't cycle stay on the ground till the oil is starting to show some temperature and the prop cycles.
 
Even if the governor is not allowing the prop to cycle, you should not be seeing 2900 rpm on takeoff. The pitch stops should be set to limit your max rpm to 2700 or thereabouts.
 
What oil temp are you using as acceptable for take off? As others have said muti grade oil in cold weather is recommended and if the oil is to cold to cycle prop I wonder how well it is flowing through the engine?
 
Thanks for the replies guys.

Oil is Aeroshell W100 Plus, been using it for ages. I've had the plane 15 mths, this issue has only showed up this winter?
I have EI for engine gauges so only assume the revs are excessive. I wait til I get the first green light on the oil temp, around 110 degs, normal ops in flight around 170-180 degs..
I may try a multi grade oil as its due for a change shortly.
I've got 40 Yrs of driving planes, many with CS props, never had this issue before? Somethings not right, diff oil first I think.

Watch this space :)
 
Thanks for the replies guys.

Oil is Aeroshell W100 Plus, been using it for ages. I've had the plane 15 mths, this issue has only showed up this winter?
I have EI for engine gauges so only assume the revs are excessive. I wait til I get the first green light on the oil temp, around 110 degs, normal ops in flight around 170-180 degs..
I may try a multi grade oil as its due for a change shortly.
I've got 40 Yrs of driving planes, many with CS props, never had this issue before? Somethings not right, diff oil first I think.

Watch this space :)

As already mentioned, the low pitch stops on the prop are not adjusted properly. Even with a slow responding gov. the low pitch stops should be set to a pitch that will limit the RPM on a normal takeoff/climb to 2700 RPM.
The Hartzell manual for the prop has all of the details.
 
As already mentioned, the low pitch stops on the prop are not adjusted properly. Even with a slow responding gov. the low pitch stops should be set to a pitch that will limit the RPM on a normal takeoff/climb to 2700 RPM.
The Hartzell manual for the prop has all of the details.

I'm not sure that's correct. The fine pitch stop should be set around 2600-2650 static RPM. As the aircraft accelerates, the governer should kick in and start to coarsen the blades to limit the RPM to 2700. If the governer is slow to react, the RPM will continue to increase with airspeed unless power is reduced.
 
Finally got around to changing the oil to a multi grade (20-50) MUCH better. The 100W I used to use was too thick when cold it seems this winter.
So nothing wrong with the beast, just needed a better oil diet:)
 
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