2-Blade MT Prop Leaking Grease

Dreamster · #1 09-09-2007, 11:41 AM

My 2-blade CS prop from MT is leaking grease form the hub. There is enough grease coming out on the back of the blade root that it gets slung on the cowl, windscreen, and VS leading edge. I don't have any airframe vibration that I could tell over what the engine produces. Is it possible that my Dual Plasma II+ ignition could be causing the problem?

Has anyone had any experience with MT Props leaking grease?

Thanks

gstone · #2 09-09-2007, 03:19 PM

I don't have details or much first hand experience but have heard it is one of MT's worst problems. I've seen 2 extra 300's with leaking seals on their MTs. FWIW.
Greg

Bob Brown · #3 09-09-2007, 08:42 PM

Call Kevin Russell at American Propeller 530.221.4470 to discuss. I think he said the MT will sling some grease continually and said not to worry about some grease being slung...you can't grease that hub (there are no grease zerks) so apparently that's how it moves lubricant through. Mine is also slinging some too, I called him and felt reassured, but I'm going to check again and see what he has to say.

RVjim · #4 09-09-2007, 10:52 PM

Quote:

Originally Posted by Dreamster

My 2-blade CS prop from MT is leaking grease form the hub. There is enough grease coming out on the back of the blade root that it gets slung on the cowl, windscreen, and VS leading edge. I don't have any airframe vibration that I could tell over what the engine produces. Is it possible that my Dual Plasma II+ ignition could be causing the problem?

Has anyone had any experience with MT Props leaking grease?

Thanks

I've been flying MT Propellers for five years. There is a fairly small amount of grease that comes out of after the propeller is first assembled. How much flight time do you have on the propeller?

There is a standard sequence that is used to document the amount of grease leakage. Feel free to give me a call.

Regards,
Jim Ayers
Less drag Products,Inc. - a MT Propeller Distributor
Southern California
(805) 795-5377

Russ McCutcheon · #5 09-09-2007, 10:53 PM

350 hours on my MTV 15 B-183-33 sense its last work done by MT USA and no grease slinging ever, not sure I like the ?its normal? answer, grease on the stabilizer, I don?t think so. Sense you cant replace the grease you best get it fixed or weight tell it stops slinging but that might mean theirs no grease left!

Russ

Dreamster · #6 09-10-2007, 06:12 PM

gstone, thanks for the data point.

Dreamster · #7 09-10-2007, 06:21 PM

Bob, I bought the prop from American and they have been helpful. I'm just trying to get a sense of whether this is a cronic problem with MT props before I decide to ditch it. Judging from the feedback there is at least a perception around my airport and on this forum of some problems with MT props leaking grease. It may be based on anecdotal experience, but the perseption is real. A little trailing out in the first few hours of operation is normal, but "slinging' at all is a problem that no prop should have. I don't buy that its designed to do that. Even if it is supposed to pepper your airplane with black spots, slinging grease all they way back to the VS is excessive. One industry expert (unbiased opinion) said they had never heard of an MT prop not leaking prior to TBO. That is not much of an indorsement.

Dreamster · #8 09-10-2007, 06:30 PM

Russ, Are you using electronic ignition and what is powerplant and airplane model?
Thanks

RVjim · #9 09-10-2007, 10:53 PM

Is everyone doing the pre-flight propeller blade inspection?

It is very important to know if the blade twist and blade movement are within the allowable limits.
It is important because excess blade movement will cause grease to leak past the blade grease seal.

During the propeller assembly, excess grease is applied to the bearing race to hold the ball bearings and bearing spacers in place. This excess grease ends up between the bearing race and the blade grease seal. When the engine is running, the grease naturally flows outward towards the blade grease seal. The hotter the propeller hub (engine oil temperature), the easier the grease will flow and the easier it is for the grease to get past the blade grease seal.

The date of manufacturer of your MT Propeller is also a consideration. The blade grease seal was changed in early 2003. All of the propellers built prior to 2003 are required to have the new grease seal configuration installed when the propeller is overhauled.

A grease leak is a symptom. This, by itself, is not a problem. (The seal change in 2003 was done to eliminatate the annoyance of excessive grease leakage.)

If there is a grease leak and excess blade movement, then there is a problem.

If you feel you have a problem, and you purchased your propeller from a sales/service distributor, then call them.
Otherwise, feel free to call me in California (805) 795-5377, or MT Propeller USA in Florida (386) 736-7762.

Regards,
Jim Ayers

Russ McCutcheon · #10 09-10-2007, 11:36 PM

Mine is on an RV-4 and is bolted to an Angle valve 200HP IO-360 with non counter balanced crank and mags, I think this is about as hard on the prop as it gets. It does light acro almost every flight, the 350 hours has been done in less then the past two years so it is all the newest stuff. These are fine props and all the brands have had these and other problems to some extent so ditching it for something else could be just trading one problem for another.

Yes there is a service bulletin or service letter about prop inspection, I follow it to the tee, mine still checks like it was new, if you have not read this service letter and are not following it, check it and others out on the MT web sight.

Russ