Overspending Prop?

[MBDiagMan]

My F has a fresh engine with about 25 hours break in time.  Went the first 20 or so hours on Mineral oil and was making 2660 RPM with everything forward on takeoff and climbout.  I changed oil and filter with 20W50 Phillips Crosscountry.  I flew it an hour or so and then went on a short breakfast run this morning.

When I was climbing out to come home, I noticed the red engine light on and looked at the JPI to discover 2770RPM.

Could the engine be breaking in, supplying more power causing this or is the prop beginning to go flat?  Could the change in oil viscosity have anything to do with it?

Plan on asking the mechanic Mondaymorning,but thought I’d get some information here.

[0TreeLemur]

Overspending???   Stoopid autocorrect.

Oil viscosity should not affect prop governor.   Its operation depends on pressure, adjustment, and function.   Something is out of adjustment or your governor has decided to go to France, so to speak.

 

[EricJ]

The governor is the first step in limiting prop speed, so it may need adjustment if you consistently get rpms that are too high.   It should work properly regardless of break-in status, so something needs adjustment or other attention.

[jaylw314]

4 hours ago, 0TreeLemur said:

Overspending???   Stoopid autocorrect.

Having had to replace a prop a few years ago, I assumed that was the actual question 

 

[MBDiagMan]

Yep, gotta love autocorrect.  Of course overspending is another term that fits in the context of aviation, so autocorrect made a possibly correct assumption.

I am anxiously awaiting my mechanics shop to open tomorrow morning.  I just thought someone may have some thoughts or experience to share and you did.

The simplicity and reliability of my little tail dragger is so refreshing as compared to the Mooney.  I have someone breathing down my neck wanting to give me a very high price for my Cessna.  Things like this make me want to sell the Mooney instead.

Edited February 20, 2022 by MBDiagMan

[0TreeLemur]

3 hours ago, MBDiagMan said:

I am anxiously awaiting my mechanics shop to open tomorrow morning.  I just thought someone may have some thoughts or experience to share and you did.

The simplicity and reliability of my little tail dragger is so refreshing as compared to the Mooney.  I have someone breathing down my neck wanting to give me a very high price for my Cessna.  Things like this make me want to sell the Mooney instead.

I'm guessing that adjusting the max rpm on the prop governor will fix your problem.   Should make something like 2660-2670 rpm in a full power static ground test.  Hopefully it won't be a big deal.  Attachments to new engines will sometimes require adjustment as things work into a new equilibrium.  I've not had the joy yet of living through an overhaul, but I'd guess squawks are common in the first 100 hours.   Good luck, looking forward to hearing about success.

[PT20J]

If it was working correctly before, then something has changed. On a McCauley governor (assume the others are similar) the adjustment screw should be safety wired. I would check that the screw is secure. You can try adjusting it on the ground -- one turn is supposed to be about 25 rpm I believe on a McCauley. A surer way is to set the prop to max rpm in the air and land without touching the prop control and then adjust the screw until it just touches the control arm.

Skip

[MBDiagMan]

Since the engine rebuild about 25 hours ago it had been reliably and consistently  holding 2660 RPM.  Yesterday it got away to about 2770 seemingly all of a sudden.  That’s what has alarmed me.

[A64Pilot]

On 2/20/2022 at 6:09 AM, MBDiagMan said:

Yep, gotta love autocorrect.  Of course overspending is another term that fits in the context of aviation, so autocorrect made a possibly correct assumption.

I am anxiously awaiting my mechanics shop to open tomorrow morning.  I just thought someone may have some thoughts or experience to share and you did.

The simplicity and reliability of my little tail dragger is so refreshing as compared to the Mooney.  I have someone breathing down my neck wanting to give me a very high price for my Cessna.  Things like this make me want to sell the Mooney instead.

Keep the 140, it’s always the go to airplane just to fly around on a late Summer afternoon with no destination, window open, elbow in the wind. Besides a tail dragger keeps your feet knowing what they need to do, it hones flying skills, you can be sloppy with a nose dragger and get away with it.

But it sux as a traveling airplane. I’ve had a couple of different airplanes, it’s the 140 that I have kept.

 

Edited February 21, 2022 by A64Pilot

[carusoam]

Something has changed…

The gov has a job to do…and something has let it not do it properly…

All knobs forward… means the pilot is operating correctly…

But, what happened at the other end of the knob is getting more interesting… 

Are those new controls that just got installed?

Are they still connected as expected?

A simple inspection might find something simple going on…

Did the knob feel any different when pushed in?  Be on the look out for any fraying of the prop’s control cable… the twist style knobs have a unique way of falling apart…

PP thoughts only, not a mechanic…

-a-

[1964-M20E]

When checking pull grease fittings on prop hub and check for motor oil.  It is rare but oil can get past the piston seal and lock the prop on fine pitch. 

[chriscalandro]

Give it a hard budget and make sure it doesn’t exceed it. A prepaid card with a set amount per month might be required. 
 

my old prop used to overspend with a 100hr inspection. I replaced it with the top prop, which so far has been much less spendy. 

Edited February 23, 2022 by chriscalandro