Prop govenor overspeed question...

[funvee]

Here's my situation....

 

When I first startup and do a full warm up I get a normal RPM of 2700 on take off with no issues.

 

In the last week or so, I've been out doing flight training for my Commercial rating and during some of the exercises such as precautionary landings and stalls etc etc and have noticed a problem with the rpm.  When I power up for recovery I notice that my prop is spinning up over 2700... closer to 2900 before it gets limited by the governor.

 

I have a note in with my AME about it but haven't heard back yet so I thought I'd post a quick question here just incase it is normal that it can overspeed like that due to the airflow on the prop spinning it up.

 

(btw... I know it might be a dumb question but I couldn't find anything with the searches I did so I thought I'd ask the Mooney crew)

 

Thanks

Shawn 

[201er]

Are you pushing the throttle in too fast? That can cause a momentary prop overspeed in any constant speed propeller. However, I think the Mooney is rated up to 2900RPM for momentary overspeeds. Still it is better to apply power smoothly to avoid stressing it unnecessarily.

[funvee]

Are you pushing the throttle in too fast? That can cause a momentary prop overspeed in any constant speed propeller. However, I think the Mooney is rated up to 2900RPM for momentary overspeeds. Still it is better to apply power smoothly to avoid stressing it unnecessarily.

 

I'm doing as slow as the CFI will let me... On those exercises she wants you to do it in an "expedited" method just like you would if you where in a life and death situation where full power immediately is a life saver.   

 

But having said that, I still try to "slow the flow" a bit and seem to be at a 2 second push to full throttle (roughly).  If I go any slower all i hear on the headset is "POWER POWER POWER".

 

What it does is, climbs to the 2900 area and doesn't come back down on it's own until I lower the throttle (or lower the prop setting).

[Marauder]

Sounds like the beginning stage of the prop governor failure I had. Would occasionally over speed, eventually I couldn't control it. Hopefully some mechanics will chime in. Ever have the sludge cleaned out of the hub?

[Alan Fox]

If the prop overspeeds for real , it will warrant a teardown, get it looked at....Iv seen what happens when the governor fails , its unbelievable....

[Cody Stallings]

Your problem is the same problem I had except I was only getting 2840, an the gov was not trying to pull it back down. First run was great though. It all ended when we removed the H-1 Gov an installed a McCauley prop gov. Even had the H-1 Overhauled, but it still didn't fix it.

[PTK]

Here's my situation....

 

When I first startup and do a full warm up I get a normal RPM of 2700 on take off with no issues.

 

In the last week or so, I've been out doing flight training for my Commercial rating and during some of the exercises such as precautionary landings and stalls etc etc and have noticed a problem with the rpm.  When I power up for recovery I notice that my prop is spinning up over 2700... closer to 2900 before it gets limited by the governor.

 

I have a note in with my AME about it but haven't heard back yet so I thought I'd post a quick question here just incase it is normal that it can overspeed like that due to the airflow on the prop spinning it up.

 

(btw... I know it might be a dumb question but I couldn't find anything with the searches I did so I thought I'd ask the Mooney crew)

 

Thanks

Shawn 

Sounds like the governor needs to be sent a message that he'll be voted out!

[N601RX]

Both Lycoming and Hartzell have SB's that deal with overspeed.  If I remember correctly the Lycoming is the more stringent of the two.  They consider any more than 3 seconds an overspeed.  The amount of inspection they suggest varies depending on the percent of overspeed.  I would tell the CFI I was simply not going to advance it that fast for practice, unless it was a real emergency.

 

http://www.lycoming.com/Portals/0/techpublications/servicebulletins/SB%20369C%20%2804-18-2012%29/Engine%20Inspection%20after%20Overspeed.pdf

[Jamie]

I would tell the CFI I was simply not going to advance it that fast for practice, unless it was a real emergency.

 

This.  Or get a rental. Or her airplane.  If it's a REAL emergency the entire airplane is expendable, all at once or in pieces, with the sole purpose of ensuring my survival. If it's not a real emergency, I have to pay for anything that happens to it.

[Shadrach]

TSOH on governor?  They start to get flakey as the wear out. I replaced my OEM unit with a PCU5000. The cost to OH the old unit exceeded the the pricing of a new PCU5000.

 

http://www.pcu5000.com/index.htm

 

There is a dealer in your neck of the woods!

 

MANITOBA CANADA
CANADIAN PROPELLER LTD*
462 BROOKLYN ST
WINNIPEG MANITOBA R3J 1M7
CANADA
TOLL FREE 800-773-6853
TELEPHONE 204-832-8679
TELEFAX 204-888-4696
info@canadianpropeller.com
www.canadianpropeller.com

[jetdriven]

I wouldn't do anything but an exchange overhaul on a prop governor. This board is full of guys who signed up for a 600$ overhaul and paid over a grand. You can get them from quality aircraft accessories.

[Shadrach]

I agree with Byron. My OH guy caled me after teardown and told me it was going to cost ~$1500 to OH.  At the time, the PCU5000 was less than that. I just checked pricing and they are just under $1800 now. so not quite the bargin they once were...

[funvee]

What are the model numbers I need if I call around for pricing? Is it:

McCauley - dc290-d1/t9

PCU5000

[meddesign]

Just had my Edoaire overhauled for 965, to use the PCU I would have needed a new bracket.  H&S Propellor in Michigan did it.  It works much better than before. I used Quality for other items, however they were only a dealer or middle man for the fuel system.  I believe they said they did not overhaul the Edoaire.  The good news for you is the bracket I would have needed was for the McCauley.

[jetdriven]

What is an Edoaire governor? I haven't heard of that.

[meddesign]

What is an Edoaire governor? I haven't heard of that.

Old,... can't get new parts, Says Weston on the casting, used Google to find some one to OH it. It worked out, very happy with the performance and response to questions and concerns.  It probably is original from 1969 or so.  Its on the TCD.