Lubrication of the M-18

Lubrication of Brakes, Control System, & etc.:

From MMOA bulletin Volume VI, Number 2 (1971):

"Many Mite owners have complained of poor brakes on Mites and blame it on their being mechanical. Ray Campbell of Deland Florida discovered that his brake cables had not been lubricated for a long time. After lubricating and working the cables back and forth to get them working freely again, he discovered that he had real fine brakes.

"Charlie Lasher of Miami also found out that lack of lubrication adversely affects the operation of the airplane. Charlie found out that the little heim bearings on the torque tubes and flap and elevator connections would cause excess drag and stiffness and cause the flaps and elevators to droop. This in turn would cause a little extra drag and the plane slowed down about 10 mph. The moral of all this is KEEP HER GREASED!"

Ben Favrholdt comments:

"Yes, it is a good idea to lubricate the Heim bearings during the annual inspection. The Mite has a lot of them, since it uses push rods for aileron control, and also for the trim (LA and C model) and elevator control. The Heim bearings use a steel ball in a bronze race to prevent 'galling' (transfer of metal)."

Garry Gramman of El Cajon, CA posted these comments in our Mitetalk forum (10-Apr-01):

"I don't know many of you have Mooney maintenance manuals, (probably not many) but there is such a manual. In the M-18C manual, on a page entitled "Landing Gear", Fig. 2, there is a drawing of of the wheels, hubs, brakes, etc., complete with shims, No. W-800 (flanged) and W-801 (plain).

"I designed my own shims and wrapped the ends around the end of the brake shoe and brazed a piece of 4130 onto the basic shim so that the the clearance between the shoes and brake drum was at a minimum, so a slight application of the brake pedals would actuate the brakes.

"The lubrication chart is Fig. 19, which says, to lubricate "exposed sections of brake cables. Oil with penetrating oil every 100 hours." I have found that when brake cables have been without lubricating oil for long periods of time, 100 hours will not be enough. In my own experience I had to do it three times in a week to loosen one of my cables. I took the inspection plates off in order to get to one section of cable just outboard of the landing gear. I put rags under the cables to catch the excess oil.
"My brakes will hold the plane at maximum runup of about 2000 RPM, and if they don't, I get the can of penetrating oil out and do it again."

Mike McCrath asked this question about general lubrication (05-Apr-01):

"My Mite Service manual recommends periodically lubicating various points ... with 30-weight motor oil. I do this, but of course motor oil is messy, collects dirt, ad nauseum, and generally needs constant attention… Is there something better on the market for Mite lube jobs -- something in a pressure can with a squirt pipe on it, say?"

Tony Terrigno replied:

"Mike......I have used and continue to use LPS 2 lube with has a rust inhibitor in it as well as providing good lubrication. It comes in a spray can with the plastic tube for better control. When using it, carefully expell the substance which foams like a head on beer. You will note that with capillary action it will penetrate the hardware and bushings for good lubing. Wipe the excess if necessary."