Oil leak MT Prop

[nathanda40]

Thanks Matt and Russ. With the pictures I shared earlier in this thread, MT says it is not an emergency fix. They say the prop should still have plenty of grease left. But I'm 64 months into a 72-month TBO so I will go ahead and bite the bullet. I'm a 10-minute flight from Sensinech Gainesville, but they want $2000 just to reseal blade #2. MT is quoting me $6200 for full O/H, and another $1200 for the governor. Since I will fly the plane to them in Deland, no shipping costs. Aside from a couple of small nicks on one trailing edge, my prop looks amazing. But I get a zero-time prop out of it. I would love the extra 20kts that Russ got, but probably not likely ;-)

Our 2002 DA40-180 went through the same thing. We were looking at a third overhaul of the MT in roughly 1k hours (though nearly 20 years, we only owned the past 2 years) and finally said to hell with the MT and swapped it for a Hartzell 2-blade. The prop was around $11k installed including trade in of the MT, which considering the exorbitant and regular overhaul needs of the MT is quite a bargain. I must say I was not very impressed with the MT propeller.

[dmloftus]

I must say I was not very impressed with the MT propeller.

I love the way the MT flies. I used to fly rentals with the McCauley aluminum and did not care for the extra noise and vibration. Have not flown their 2 blade composite.
With my plane at MT, I'm likely going to have them also O/H the governer for an additional $1200. Have others done the same when they do a prop O/H?

[Steve]

I must say I was not very impressed with the MT propeller.

With my plane at MT, I'm likely going to have them also O/H the governer for an additional $1200. Have others done the same when they do a prop O/H?

Prop governors are typically overhauled at engine overhaul, or after a prop strike. If you aren't having any difficulty with it, why do it?

[dmloftus]

Picked up my DA40 yesterday from prop overhaul at MT Propeller in Deland, FL. Great service by Brett and the team. As mentioned earlier in this thread, I had a minor grease leak and I was 5 years into a 6 year TBO (although not mandatory for Part 91) so I went ahead and bit the bullet. I had also picked up a few nicks from FOD on my Vegas trip last summer that I was looking forward to having repaired. The last time it was overhauled by the previous owner, it was done by a shop in NY that shipped the blades to Deland for refinishing. Sensenich locally offered to do the same thing, but I'm guessing my grease leak could have been a factor of an outside shop doing the reassembly. I wanted MT to do all of the work so I had only one shop to point to if there was an issue. Brett explained there is a special seal that they use on our Diamond props to form a tighter seal. He advised that one side effect of the tighter tolerances is initially the prop takes a second or two to follow commanded pitch changes, ie if you're running 2200 and push your prop lever forward, it will take a second or two for the prop to reach 2400rpm. While there is technically no break-in period, the prop should behave normally after about 10 hours. He mentioned there might also be a few grease streaks up the prop for a few hours as everything settles in, but should be totally clean after a few hours. By the time I reached Atlanta, the prop seemed to regain normal responsiveness and I noticed no grease streaks on the blades. Prop looks spectacular, just like new, and I was impressed with the operation in Deland. While there are many comments about the fragility of these props and some preferences for aluminum, I love the way these props fly - smoother, quiter, better balanced. And I would be reluctant to go to a 2 blade with the increased chance of a prop strike. Now maybe if I could get my hands on the new MT 11-blade prop ;-)
A few pictures of the MT Deland operation:

Before

After

In process or finished

Refinishing

Brett pointing out repairs to wooden core

Unlike aluminum prop dings, composites aren't filed down. They add back, resurface, and repaint

[Rich]

Reinstalled my prop today. For those who haven't done it, it's pretty tedious (as are all CS props on Lycomings). The six pseudo-bolts need to be started and screwed in place in synch with each other about 1/8 inch at a time. Not shown here is the process of safety-wiring same in pairs - threading the safety wire through the center of each of the roll pins. Using an engine hoist to support the process is of immense help.

[michael.g.miller]

Picked up my DA40 yesterday from prop overhaul at MT Propeller in Deland, FL. Great service by Brett and the team.

+1. My DA42 had an MT propeller with delaminating paint on the back. It was out of warranty by a few years. Brett and his team not only fixed the problem, but gave me an entirely new set of blades, completely free of charge. Very awesome group of people.

And a really nice feature of the MT propellers is that you can 5-minute epoxy away a good majority of nicks (just let it cure for 24h+!). I've always been worried about being stranded at some gravel bush strip, so this is a big plus for me.

[jwx96]

I’ve used the 5-minute epoxy too. I wait 3 minuets after mixing to apply it. That way it doesn’t spread or settle.

[dmloftus]

During my current annual, Southtec picked up that my prop is still a bit slow to return to run-up RPM when cycling the prop, about 40 hours after my prop overhaul last December. I talked with Brett at MT to understand whether I need some type of adjustment. It definitely takes several seconds to get back to 2000 after cycling the prop at run-up. I don't really notice it in flight as, at higher RPM's, the prop reacts much quicker. He explained that instead of the normal C-clamps they used to hold the blade to the hub on the original DA40 (and all other MT models), MT Germany has redesigned the MT/DA40-180 combo with a big nut that screws onto a threaded ferrule, torqued to a specific spec. This is to eliminate the issue specifically with our planes of slinging grease from the seal. One byproduct is that the prop is slower to accelerate at lower RPM. He assured me that nothing is wrong and warned me about letting anyone adjust it. Just an FYI if you have them overhaul your prop.

[Rich]

Thanks, David. I was just about to post that mine is behaving the same after last fall's overhaul. In fact it never seems to return to 2000 RPM at runup unless I goose it. No problems in flight, as you mentioned.