OTHER:Mechanics - General - Lubrication
Mini 500 (Talon) Revolution Helicopter Corp.
Transmission uses 1 quart of Revlube #E0015 gear lube.
Oil sight gauge, oil temperature gauge and optional chip light.
The spiral bevel gear that drives the tail rotor is located in the transmission lower housing and it operates as a centrifugal pump for the gearbox lubricating oil. This driving spiral bevel gear is rotating at the engine speed of +/- 6000 rpm.
Note:[Source ~ MDD p.82]
The normal single stage transmission usually has sufficient surface area to dissipate the heat developed in the transmission of powers up to 150 to 175 horsepower, providing the transmission housing includes external ribs.
It is important to prevent operation of gears or ball bearings in an excessive amount of oil. Thus in a splash system the oil level should be maintained so that the gearing only dips into the oil, rather than being submerged.
Suppliers of Dry Sump Pumps
Peterson Fluid Systems
See list in Folder B166
Supplier of Oil Pumps
2055 Columbia ( between Main & Cambie & 4th & 5th)
They handle all sorts of small stand alone oil pumps
PRA Date: January 31, 2000: Author: Hennie Roets: Subject: How to get oil to the top bearing of the gearbox
I did the following to get oil to the top bearing in the gearbox:
I took two grease nipples and took the spring and ball out and drilled the hole bigger to about 2 millimeter. Next I drilled and tapped two holes in the gearbox. The first hole is about 15 degrees to the left of the pinion shaft if looked from the top of the gearbox and on the same height as the teeth on the crown wheel. On the nipple that I put in here I fixed a piece of three millimeter steel pipe that go al the way to within 0.5 millimeters of the teeth. I opened the one side of this pipe for about 5 millimeters. (towards the pinion). The second hole was drilled just above the top bearing and the nipple screwed in without any mods.
For testing purposes I connected the two nipples with a piece of 3 millimeter transparent tubing.( oil resistant tubing will have to be used) I found that at about 100 rotor r.p.m. the oil started flowing up the tube and for what it is worth I do not worry any more about lubrication on the top bearing.
I copied this out of a previous post of mine. If there is any questions please ask. This is really a very cheap fix.
PRA Date: February 03, 2000: Author: Hennie Roets: Subject: cooling the oil
I just got an idea that might work in cooling down the transmission oil.
A friend of mine cooled down his 1834 cc VW engine oil installed in a fixed
wing using the following and it truly worked:
Instead of the normal radiator type of oil cooler for which he had no space
he used an aluminum pipe 3/8 inch diameter and coiled it into a spiral.
The lenght he used was about 36 inches and believe me it did work.
If we use my mod to get the oil to the top bearing we might as well pump the oil
through this coiled pipe and put the coil in the way of the air scoop that force
air down from the top of the turtle deck down onto the gearbox.
PRA Date: February 10, 2000:
The electric pump that is being discussed for the mini 500 delivers 10 litres per minute and can be used constantly at 130 'c and the flow is high. Using the synchro gears as a gear pump is 4X this.
PRA Date: April 14, 2000:Author: CA BEATY: Subject: Groen gyroplane
The right angle gearbox is a crownwheel-pinion affair, running dry sump with an oil pump spraying oil on the contact area. Submerged gears can consume prodigious amounts of power just from churning oil and present a difficult cooling problem.
PRA Date: May 4, 2000
Also note the orange tele-temp strip (on Mini 500 picture). This is a real good idea to keep an eye on transmission temps.
Lu Zuckerman: PPRuNe, January 2, 2002
There is a means of detecting impending failure long before the generation of chips and chunks and that is SOAP or Spectrometric Oil Analysis Program. This system if you are not familiar with it requires the periodic sampling of the oil and sending it to a laboratory that is equipped with the necessary equipment to measure the build up of wear metals in the oil. The wear metals are actually a part of the oil and the oil then becomes an organo-metalic compound which can be measured to detect the specific wear metals which in turn can tell you what type of component is wearing and at what rate. The rate is monitored as a part of the test and when it is determined that the suspected part is wearing at too rapid a rate the lab strongly suggests that the gear box or the engine be removed and inspected internally. Frequent filter changes will help but frequent oil changes will not as the oil change will dump the metal chips in the sump but it does not help in detecting the presence of wear metals. If you find chips and chunks in the oil when it is being drained then it is already too late. In the next flight it is possible that you can suffer a catastrophic failure. As a scientific test they placed chips in new oil samples and the SOAP test could not detect them. Using old oil and those same chips the SOAP test detected the wear metals but not the chips.
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Last Revised: June 16, 2003