Using flo torq iv

[sony224422]

I finally got a new used lower unit, and swapped everything over. I had the flo torq iv on my other lower unit because it chattered really bad at low rpm with my q3 15.25x13. I think I put it on correctly, tappered part of the thrust washer towards the shaft so that the shaft would fit in it and then the prop and flo torq and then tightened down the nut. I didn't put a torque wrench on it, but it seems looser to me than it did before. But I can't remember. I went out and still hit 5200 rpm and 32.5 mph which is the same as before, but I feel like there's a little vibration at 1100-1500 rpm. I have a video attached. The weird squeaking noise is the prop touching a leaf. I spun it backwards first and then forwards the second time, and pulled it in and out and then a little side to side. It doesn't seem like the shaft is moving though?

https://photos.app.goo.gl/lja1Zu2eigx0ljx33

[Jason2tpa]

Not able to view the video, requires google drive access. Youtube is a better video sharing platform that all can view.

The propeller nut torque spec is 40ft/lb. Having recently installed a new prop and torqued the nut, I can tell you that seating the nut to 40ft/lb with a long lever arm torque wrench takes some effort. Therefore if you've tightened the nut by only using a standard wrench, the nut is most likely not close to 40ft/lb.

This could be the reason why you believe it's loose. Before troubleshooting the lower unit any further, I'd first apply the spec torque to the nut then test.

[99yam40]

prop should not be loose on the shaft when even snugged down by a regular wrench,
something is wrong if that is what you are saying

[sony224422]

I agree, however flo torq does say here will be some movement because of their design. I'm just not sure if it's the normal amount or not. I'll try to get a different host for the video

[Captn Dave]

I recently put a Q3 with a Flo-Torq on my engine and have no chatter at all.

Remove the prop and take photos of the hub assembly and washers.

Any chatter problems that I ever heard about were at idle and I believe the engine in neutral.

[sony224422]

https://photos.app.goo.gl/lja1Zu2eigx0ljx33 see if that will work?


I'll pull the prop and see if anything looks weird too

[Captn Dave]

What's going on with that FWD-AFT play?

[sony224422]

Flo‑Torq III and Flo‑Torq IV Propeller Installation
1. Install and align all of the components.
2. Tighten the nut to the specified torque.
3. Bend the tabs of the tab washer into the rear thrust hub.
4. The drive sleeve must be locked between the forward thrust washer and aft adapter.
a - Flo‑Torq III propellers
b - Flo‑Torq IV propellers
Description Nm lb‑in. lb‑ft
Propeller nut 74.6 55
5. Rotate the propeller to verify interference or binding does not exist between the gear housing and the propeller.
NOTE: A small amount of rotation play and forward aft play is normal.

I am thinking that i didn't snug it down enough to seat the thrust washer and its a little looser than it should be. Im 99.9% positive i have the thrust washer on correctly

[DennisG01]

If the plastic hub was removed, or wiggled out a bit during the time the prop was off, that "could" be the issue. I always bang the plastic hub fully into the prop, until it bottoms out, before putting the prop on. Tightening the nut properly SHOULD do the same thing, but you never know.

I've personally never noticed any play due to the hub-to-prop fitment. The only play I've ever noticed is due to the minute propshaft movement.

[sony224422]

I talked to Ken Reeves, he told me to make sure the shop gave me back the correct thrust washer as well. It requires the 853948 washer from flo torq. So I need to pull it off and check to make sure thats the correct one as well. And if it is, I'll reinstall everything as new to make sure its all correct

[Jason2tpa]

I re-read your initial post, now realizing the hub kit you're speaking of was not newly installed. So if I'm reading you correctly, all you've done is replace the LU. You're using the same prop and hub kit you used on your previous LU. Is this correct?

I watched the video. Is this video made before the prop nut had been torqued to spec? If not, waste of time here speculating as to why you're experiencing vibration when the nut is not properly tightened. Refer to my previous reply regarding prop nut torque.

Having just installed a flo-torq hub kit in my prop I'm familiar with its installation. If the drive sleeve is installed too far aft into the prop, a space will exist between the forward thrust washer and drive sleeve. And if this occurs, the prop will have a noticeable forward-aft movement as you push and pull.

Since the installation/removal of the flo-torq hub kit system is very easy, I recommend removing the hub from the prop and reinstall. After inserting drive sleeve, lay the thrust washer down on top of the inner hub. The washer should be in contact with the drive sleeve, but the drive sleeve shouldn't be driven to far aft causing the washers outer most diameter be raised above the inner hub. The outer most diameter of thrust washer should lay flush on top of inner hub.

[Jason2tpa]

Flo‑Torq III and Flo‑Torq IV Propeller Installation
1. Install and align all of the components.
2. Tighten the nut to the specified torque.
3. Bend the tabs of the tab washer into the rear thrust hub.
4. The drive sleeve must be locked between the forward thrust washer and aft adapter.
a - Flo‑Torq III propellers
b - Flo‑Torq IV propellers
Description Nm lb‑in. lb‑ft
Propeller nut 74.6 55
5. Rotate the propeller to verify interference or binding does not exist between the gear housing and the propeller.
NOTE: A small amount of rotation play and forward aft play is normal.

Referencing above in bold...ive torqued my prop nut to spec and there does exist a small amount of play when manually pushing/pulling prop. After you've verified correct thrust washer and proper installation of hub as I previously noted, and you are still experiencing vibration, I'd then rule out the issue being the prop and/or hub. At which time this new used LU will be the issue.

[Jason2tpa]

Flo‑Torq III and Flo‑Torq IV Propeller Installation
1. Install and align all of the components.
2. Tighten the nut to the specified torque.
3. Bend the tabs of the tab washer into the rear thrust hub.
4. The drive sleeve must be locked between the forward thrust washer and aft adapter.
a - Flo‑Torq III propellers
b - Flo‑Torq IV propellers
Description Nm lb‑in. lb‑ft
Propeller nut 74.6 55
5. Rotate the propeller to verify interference or binding does not exist between the gear housing and the propeller.
NOTE: A small amount of rotation play and forward aft play is normal.

Referencing above in bold...ive torqued my prop nut to spec and there does exist a small amount of play when manually pushing/pulling prop. After you've verified correct thrust washer and proper installation of hub as I previously noted, and you are still experiencing vibration, I'd then rule out the issue being the prop and/or hub. At which time this new used LU would be the issue.

[sony224422]

Well I went through it all again. Took everything off and started over. The thrust washer is correct. Put it back on and torqued it to 55 ft lb and same thing. So I measured it. It's exactly 1/8th inch of play so I guess it's fine

[Jason2tpa]

I went out and still hit 5200 rpm and 32.5 mph which is the same as before, but I feel like there's a little vibration at 1100-1500 rpm.

As noted in my last, a small amount of play is normal and I would consider 1/8" to be small. However, referencing your quote above, if you're still getting a vibration I would not consider this normal.