Hydraulic drive for Lycoming accessory case.

[Vance]

Some Lycoming engines have a drive adapter that bolts to the accessory case. It has a bearing support and a female splined drive for the hydraulic pump for landing gear.

I would like to find both the adapter and the pump.

Even a part number would be helpful.

I suspect that there are plenty lying around when the engine is used on an experimental without retractable gear.

My O-290 has a plate over this spot but the gear is in place behind the plate.

I want to build a hydraulic drive for my pre-rotator.

My 1988 Toyota Corolla electric starter doesn’t seem to be quite up to the job. I have replaced it twice and I only pre-rotate to 100 rpm.

I would be grateful for your help.

Thank you, Vance

[barnstorm2]

Interesting.

I am in the same boat. My Twinstarr's electric starter only pre-rotates the 30 foot blades up to about 110ish.

The Marchetti's I have seen give up their alternator/generator for a wonderlick pre-rotator. I am not willing to give up my generator.

I will have to see if my 0-320 has a spot on the accessory panel too...

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[barnstorm2]

My Lycoming manuals are at the Hangar so I don't have a cross-reference my this might help with research...

http://cgi.ebay.com/ebaymotors/lycom...QQcmdZViewItem

http://cgi.ebay.com/ebaymotors/lycom...spagenameZWDVW

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http://www.salvagedairplanes.com/use...00&cur_page=26

http://www.aircraftaccessoriesofok.c...ml?catId=42894

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[Vance]

Thank you Tim,

That is it exactly unless the O-540 is different ffrom the four cylinder engine.

I have never bought anything on e bay. I would appreciate help.

I would be happy to pay $120 for the two parts and shipping.

Thank you, Vance

[Timchick]

I don't know what your engine setups look like. Is there any way to maybe go to something like this Ultrawhite Wunderlich setup?

[Vance]

Thank you Tim,

I am interested in a hydraulic pre-rotator.

With this adapter and hydraulic pump I will use a simple diverter valve to drive one of Ernie’s hydraulic motors and bendix set ups.

Thank you, Vance

[barnstorm2]

Originally Posted by Vance

Thank you Tim,

That is it exactly unless the O-540 is different from the four cylinder engine.

I have never bought anything on e bay. I would appreciate help.

I would be happy to pay $120 for the two parts and shipping.

Thank you, Vance

Vance,

Buying from ebay is like buying from a flea markets' parking lot. No warranties, no returns and you have to know enough about an item to ask the right questions.

I will be happy to use my ebay account to place bids on the items for you. The gear is currently at $30 and the pump at $70.

If you send me an email at gyro.pilot@yahoo.com and tell me the bid amount you wish to place on each one and questions you want me to send to the seller I will send the questions and place the bids for you.

Please keep me posted on how the project goes. If it works out for you I may try to dupicate it myself.

.

[barnstorm2]

Originally Posted by Timchick

I don't know what your engine setups look like. Is there any way to maybe go to something like this Ultrawhite Wunderlich setup?

I was hoping Tom Milton would jump in here with a plug-n-play solution.

I don't see a way to add a plate and mount a wheel to my application.

Here are photos of Randy's Marchetti and the wonderlick installation on it's Lycoming 0-320.

Note that the wheel runs on the band that normally is the pulley for the alternator/generator (the back of the engine starter ring gear).

I will NOT give up my generator.

I don't know if it would be safe to run this wheel on top of my generator belt....




In this photo you can see that the wheel mounts to the Lycoming case bolts on the top of the case:




Here you can see that a 'band' or smooth pully has replaced the groved pully that normally holds the generator belt.



Here is a Top-Down view of my Twinstarr. Note the belt pully where the pre-rotator wheel would need to grab.

[Vance]

Thank you Tim,

I sent you an email.

The part numbers are very helpful.

I would also like a pump so perhaps a junk yard would be the place to start.

I would prefer a hydraulic pre-rotator.

Thank you, Vance

[JEFF TIPTON]

Vance, the drive pad you are talking about is usually used to drive a wet or dry vacuum pump. In any case do not run the engine without something bolted to it. It has a small hole at the bottom that lubricates the wet vacuum pump and if left uncovered will result in total loss of oil in a very short time.

The caution out of the way, you probably will not find this pump in any of the engine manuals as it is not required for the operation of the engine. Instead it will be found in some airframe manuals as the pump would be used to supply hydraulic pressure to the retractable landing gear or flaps and is more prevalent on Continental engines.

All this being said part 1280103-8 is a landing gear hydraulic pump used on a Cessna 210 in the 1967 to 1969 era. Now this is mounted on a Continental aircraft engine but would not be a problem. The vacuum pump pad is military standard (MS) and is used by most of the certified engine manufacturers. Lycoming, Continental and Franklin.

The pump and adapter are one piece and I would search the salvage yards to see if they have a serviceable unit.

Hope this helps.

[Timchick]

Tim O, It looks like there may be enough space on the back side of the flywheel just above the belt for the Wunderlich wheel to press against if it's done like the photo I posted. Just figure out how to make a bracket to hold the Wunderlich assembly.

I once saw a prerotator on a gyro (can't remember what gyro or what engine) and the wunderlich wheel was pressing against a belt. Not sure how well it worked or if it wore the belt much.

[Vance]

Thank you Jeff,

As always, your vast eclectic experience is most valuable.

I have a hydraulic pump that would fit into that adapter for the vacuum pump. It pumps enough oil for about an 18 horsepower hydraulic motor. I also have a 22 horsepower hydraulic motor. I don’t know if the adapter would be strong enough to run it.

Thank you for the tip about the hole.

Thank you, Vance

[JEFF TIPTON]

If it helps the pump I mentioned will produce 3,000 PSI. Not sure about the volume.

[Earthboundmisft]

Vance, the pump will be moving fluid while the engine is running. I guess you could dump it into the reservoir, sort of a constant loop, when not in use. I thought of the same idea for my IO-320. May have to run it through a cooler? By the way, thank you for your time at Bensen Days. You inspired me. I havent forgotten to send you the memory stick for additional photos of your machine, had a few issues on the homefront since. Keep us posted, Thanks, Mike Hughes (Earthboundmisft)

[Vance]

Hello Michael,

I enjoyed our time at Bensen days. I will still send the pictures if you will send me the stick.

The pump runs all the time when it is used for the landing gear. I did some experiments with hydraulic pumps and motors. I ran a hydraulic pump that was driving a hydraulic motor that could deliver 22 horsepower. I ran it first with no load and then I had my lathe turning my mill head that has a very inefficient varispeed belt on it. I ran it for 10 hours with two quarts of automatic transmission fluid and the oil was warm to the touch. The belt and chives where hotter than the oil. I am sure it would heat up faster if I put a big load on it. I run the pre-rotator for less than a minute so I don’t think heat buildup will be a problem. The lack of heat when it was running with a light load would suggest to me that it isn’t using much power when it doesn’t have a load.

I like things that are easy and cheep to try.

I am not happy with the reliability or the performance of my Toyota starter.

My radio doesn’t work when I am using the pre-rotator and I have missed some important information.

Thank you, Vance