Hartzell prop (or govenor?) squealing on startup

Any DA40 related topics

Moderators: Rick, Lance Murray

User avatar
mhoran
4 Diamonds Member
4 Diamonds Member
Posts: 476
Joined: Fri May 23, 2014 11:56 pm
First Name: Matt
Aircraft Type: DA40
Aircraft Registration: N269RB
Airports: KLDJ
Has thanked: 121 times
Been thanked: 244 times

Hartzell prop (or govenor?) squealing on startup

Post by mhoran »

During the last few startups my prop / governor has started making what can be best described as a squealing noise. It reminds me of the noise that the MTA busses make in NYC sometimes. Here's a video: https://photos.app.goo.gl/8dQjWpYKy8hwPxhT7.

I tried to capture the instrument panel but it didn't go too well. However, nothing jumps out as an issue there. The noise goes away pretty much immediately. I'm not sure how concerned I should be about this.

I've reached out to the shop that sent my prop and governor out at overhaul but am wondering if others are familiar with this sound / issue.
User avatar
smoss
5 Diamonds Member
5 Diamonds Member
Posts: 742
Joined: Sun Dec 12, 2010 12:18 am
First Name: Steve
Aircraft Type: DA40
Airports: KVGT
Has thanked: 57 times
Been thanked: 134 times

Re: Hartzell prop (or govenor?) squealing on startup

Post by smoss »

perhaps a slipping alternator belt?
Steve
DA40 XL
User avatar
Steve
5 Diamonds Member
5 Diamonds Member
Posts: 1953
Joined: Thu Aug 12, 2010 1:23 am
First Name: Steve
Aircraft Type: DA40
Aircraft Registration: N432SC
Airports: 1T7
Has thanked: 81 times
Been thanked: 493 times

Re: Hartzell prop (or govenor?) squealing on startup

Post by Steve »

smoss wrote: Tue May 30, 2023 1:01 pm perhaps a slipping alternator belt?
That's what I was thinking. Check the belt tension.
User avatar
mhoran
4 Diamonds Member
4 Diamonds Member
Posts: 476
Joined: Fri May 23, 2014 11:56 pm
First Name: Matt
Aircraft Type: DA40
Aircraft Registration: N269RB
Airports: KLDJ
Has thanked: 121 times
Been thanked: 244 times

Re: Hartzell prop (or govenor?) squealing on startup

Post by mhoran »

Good call. The belt is brand new and of course the alternator came off for the overhaul. I'll get that checked out.
User avatar
mhoran
4 Diamonds Member
4 Diamonds Member
Posts: 476
Joined: Fri May 23, 2014 11:56 pm
First Name: Matt
Aircraft Type: DA40
Aircraft Registration: N269RB
Airports: KLDJ
Has thanked: 121 times
Been thanked: 244 times

Re: Hartzell prop (or govenor?) squealing on startup

Post by mhoran »

Measured the alternator belt stretch in accordance with Lycoming SI 1129 and confirmed the belt is too loose. But I couldn't figure out how to adjust it. Looked like I'd have to remove the air filter and a bunch of other stuff so I'm going to bring it to the shop.

I found my exhaust burned through my cowling for a third time so I need to get that looked at. By a different shop since the other one can't seem to get it right.

Pretty frustrated to have come back from annual with a whole bunch of squawks I still have to get fixed.
User avatar
dant
4 Diamonds Member
4 Diamonds Member
Posts: 274
Joined: Wed Jul 21, 2021 4:45 am
First Name: Dan
Aircraft Type: DA40
Aircraft Registration: N787DM
Airports: KPAE
Has thanked: 49 times
Been thanked: 59 times

Re: Hartzell prop (or govenor?) squealing on startup

Post by dant »

I found my exhaust burned through my cowling


...Do tell. Three times? I didn't realize this was a thing to watch out for!
User avatar
mhoran
4 Diamonds Member
4 Diamonds Member
Posts: 476
Joined: Fri May 23, 2014 11:56 pm
First Name: Matt
Aircraft Type: DA40
Aircraft Registration: N269RB
Airports: KLDJ
Has thanked: 121 times
Been thanked: 244 times

Re: Hartzell prop (or govenor?) squealing on startup

Post by mhoran »

I was told to check that the muffler is secure prior to every flight. I always do this, but the issues below have in the first two cases been blamed on a loose muffler. I'm fairly certain that it was not loose prior to all damage, but alas. I'm not sure why a fix has been so elusive and it's frustrating to have to fix this every year.

First; muffler too close to bottom of cowling:
PXL_20220430_185105702.jpg
Second; again, muffler too close to bottom of cowling:
PXL_20230309_205344527.jpg
Third; muffler to close to side of cowling (and bottom, but side burned first):
PXL_20230604_202454966.jpg
PXL_20230604_205021799.jpg
User avatar
Rich
5 Diamonds Member
5 Diamonds Member
Posts: 4592
Joined: Mon Aug 30, 2010 12:40 pm
First Name: Rich
Aircraft Type: DA40
Aircraft Registration: N40XE
Airports: S39 Prineville OR
Has thanked: 145 times
Been thanked: 1180 times

Re: Hartzell prop (or govenor?) squealing on startup

Post by Rich »

mhoran wrote: Tue Jun 06, 2023 12:12 am I was told to check that the muffler is secure prior to every flight. I always do this, but the issues below have in the first two cases been blamed on a loose muffler. I'm fairly certain that it was not loose prior to all damage, but alas. I'm not sure why a fix has been so elusive and it's frustrating to have to fix this every year.
There's an art to getting this properly installed. Positioning the muffler bracket fore/aft and rotationally is critical. And you want the hanger restricted so it can't slide left and right on that bar attached to the firewall.
2002 DA40-180: MT, PowerFlow, 530W/430W, KAP140, ext. baggage, 1090 ES out, 2646 MTOW, 40gal., Surefly, Flightstream 210, Orion 600 LED, XeVision, Aspen E5
User avatar
mhoran
4 Diamonds Member
4 Diamonds Member
Posts: 476
Joined: Fri May 23, 2014 11:56 pm
First Name: Matt
Aircraft Type: DA40
Aircraft Registration: N269RB
Airports: KLDJ
Has thanked: 121 times
Been thanked: 244 times

Re: Hartzell prop (or govenor?) squealing on startup

Post by mhoran »

Take Flight, my local Diamond service center, tightened to the alternator belt and all is well. No more squealing on startup nor low volts annunciation. Oddly they noted that the belt seemed run out and the alternator was at its maximum adjustment point. But the belt should be brand new

Regarding the muffler, Take Flight adjusted the strap and it's a bit better. But I've requested some replacement mounting hardware from Power Flow at I'm not comfortable with "good enough" being sufficient for my cross country trip.
User avatar
Steve
5 Diamonds Member
5 Diamonds Member
Posts: 1953
Joined: Thu Aug 12, 2010 1:23 am
First Name: Steve
Aircraft Type: DA40
Aircraft Registration: N432SC
Airports: 1T7
Has thanked: 81 times
Been thanked: 493 times

Re: Hartzell prop (or govenor?) squealing on startup

Post by Steve »

Check the P/N on the belt. Maybe the service center installed the incorrect belt - there are 3 different length 3/8 inch alternator belts listed in the IO360-M1A parts catalog. Go one size smaller.
Post Reply