Anyone else Broke their hydro pumps mounting ears?

[GyroRon]

I found on my last preflight inspection that the mounting ears on my hydro pre rotator pump were cracked. After taking off the bolts that hold the pump on I discovered that one ear was completely broken in two and the other was just cracked. I tried to fix it with JB weld but then remembered this is a part you don't cut corners on.... :eek:

So I contacted Ernie about it to see if I could find out why and see if I could buy just a new flange for my pump. Ernie doesn't know why it failed and there has only been a few failures to date. He could only sell me a new pump and his advise was to try to find a local shop to try to buy parts or a new pump locally.

I was able to find a shop here in Charlotte N.C. that had the pumps and parts for them for sale. Was able to get a new flange installed for only 28 bucks! :) Instead of spending 200$ to buy a new pump! :eek:

while at the hydro shop they showed me a different mounting flange that uses four bolts instead of just two. To make my pump work with this flange I would have to make a new aluminum plate for the pump to mount onto. If the new two ear flange breaks I will be trying a four ear one next time.

Anyway if you got a hydro pre rotator, you better take a look at the mounting flange for hairline cracks - that is all I saw on my preflight - If you need a new flange and can't find a parts house in your backyard, let me know and I will put you in touch with the place here.

[Sonnyj]

Hiya Ron sounds like your releaf pressure is set too high,you could try steping it down.

[twistair]

Ron,

I believe mounting ears cracking is usual for standard Domin's prerotator mounting (my English isn't enough to explain why). I saw these many times. The thinner is the pump plate and the more loosen is the center hole in the pump plate (which the round flange of the pump sits in) the faster you see these cracks. What we do with this is to fabricate two small brackets (or plates) of 3/8"...1/2" which would press mounting flange with these two bolts. These brackets should cover mounting ears thus they distribute bending loadings which are applied to the mounting ears when you tension the prerotator belt . I can post photos if you wish - though it's easy to imagine how the brackets should works.

Just my 2 cs (copecks :)

[Texas Armadillo]

There'a a Domonator in our club, his flange broke too. He said it was semi-common for them to break. He made a new two flange "thicker and better". I could ask him for the spec's if yours breaks again and you don't wish to go the 4 hole route.

[Doug Riley]

It's happened before and been discussed here before. If you stay with the two-bolt flange, very carefully round off the corners of the fender washer that goes under the bolt heads. Make certain the washer doesn't dig into the radius that connects the flange ears to the center section of the flange.

Also make certain that the two flange ears are absolutely flat with respect to each other. If there's even a little "dihedral" angle between them, then they'll tend to crack when you cinch down the bolts. Level then off with a file.

Mine cracked early in the game but have behaved themselves ever since I replaced the flange and did this little TLC exercise.

[GyroRon]

I have never heard of this happening before or discussed before till now. The only other time I knew of this happening was I saw that Chuck Irbys machine had cracks in his flange when I saw him at SX days fly in back in July.

My Old Red dominator had 100 hours when I last saw it and still is on it's first flange, never had a crack. My new machine has about 30 hours on it now and one crack so far.

I had tried to repair the old flange with JB weld but never reinstalled it. I bought a new one. I took the old one and put it in a vise and used pliers to try to break it again - to see how strong the JB weld was. It broke with little effort at all on the side that had broken completely off, and broke very easily still on the side that just had a crack. I inspected carefully the cracked side to see how much material was still holding this on the gyro, and it was only maybe 5 percent of the total area of the crack. Had this broke off in flight it may have jammed the pre rotator on...

the new flange was not perfectly straight across. Too late to do anything cause I installed it and flew it already. I did check my fender washers and they were riding up onto the area you are are talking about Doug. I grinded away alot of the washer so now the washer only contacts the flat portion of the ears.

Alex and Jeff.... Yes more details and more pics please!

the Four ear flange would not be hard to install. It would require a new plate to mount it to, but that is it. 4 is better than 2 right?

[Shadow]

If this had happened on a RAF there would be at least 50 entries by a few RAF bashers castigating RAF everything from improper manufacturing, to immoral attitudes about safety, to sacrificing the first born son.

Since it is not RAF the manufacurer gets a free pass. :rolleyes:

[GyroRon]

No shadow your right, RFD needs to come up with a fix for this. Bash away

These hydro pre rotator systems aren't cheap and if these break in flight who knows how bad it could turn into, it could go through the prop, could try to engage the pre rotator, etc...

I personally don't bash Ernie, cause he is a good guy, Honest, willing to admit there is a problem - He told me on the phone he kows there is a problem with these units and is trying to design something to fix it - and lastly I consider him a personal friend.

RAF on the other hand..... Well I just don't think it is apples to apples.

[KenSandyEggo]

"I personally don't bash Ernie, cause he is a good guy, Honest, willing to admit there is a problem - He told me on the phone he kows there is a problem with these units and is trying to design something to fix it - and lastly I consider him a personal friend."

Same goes for Don......hey.....stop......whoa........my nose just hit the wall and I can't get it through the doorway.

[Shadow]

My Halo isn't that shiny that I can throw stones. :rolleyes: Normally, unless I have something constructive to add I try to remain silent. In this case I could not resist commenting that if the shoe had been on another foot (RAFs for example) several bashers would have been all over it attempting to tarnish the shine. Its a shame they don't realize that when you point an accusing finger at someone there are three other fingers in that same hand pointing back at you. :p

I meant no dispersions on Ernie. I think he does a very comendable job with his efforts to improve the gyro and sell a reputable product. :)

[GyroRon]

Well I agree wholeheartedly with you Shadow. I think the RAF bashing can be a little over the top at times, and I am guilty of being a stone thrower myself at times. The difference between RAF and RFD is RAF's flaws KILL people, RFDs flaws just cause dominator owners a pain in the ass getting their gyros fixed so they can fly again.

I do think that it is crap that a few of the other gyro manufactors that sell machines that can be just as dangerous as a RAF get by without any fuss. I know RAF outsells most others, so that may be the reason for the focus on them, but... I know a Stock KB-3 has to be just as dangerous as far as buntovers go as any Stock RAF. Why does no one bother to slam KBM? Maybe it is out of respect for Ken and his family? But they are still marketing a lethal design....

[KenSandyEggo]

"I think he does a very comendable job with his efforts to improve the gyro and sell a reputable product."

Does this apply to RAF, along with being truthful? If it did, then when they screwed up and made an honest effort to notify the owners, tell the truth, not try to cover it up with lies and offer a proper fix, maybe they'd be treated the same way as Ernie. They don't come close to doing any of that.....therefore it's "bashing" in your book? You can't compare the way RAF does business to the way Ernie does business, therefore your hypothesis doesn't hold water.

[Shadow]

The difference between RAF and RFD is RAF's flaws KILL people, RFDs flaws just cause dominator owners a pain in the ass getting their gyros fixed so they can fly again.
Contradiction :confused:

and if these break in flight who knows how bad it could turn into, it could go through the prop, could try to engage the pre rotator, etc...
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Does this apply to RAF, along with being truthful? If it did, then when they screwed up and made an honest effort to notify the owners, tell the truth, not try to cover it up with lies and offer a proper fix, maybe they'd be treated the same way as Ernie. They don't come close to doing any of that.....therefore it's "bashing" in your book? You can't compare the way RAF does business to the way Ernie does business, therefore your hypothesis doesn't hold water.
Its a shame they don't realize that when you point an accusing finger at someone there are three other fingers in that same hand pointing back at you.

One finger at RAF - - - - three fingers at you. :p
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The Shadow

[GyroRon]

Maybe I am contradicting myself - wouldn't be the first time - but I hardly think my pre rotator getting loose will kill me. Could cause a emergency landing though, if the prop is damaged or the pre rotator is banging the bendix up into the ring gear. A RAF and it's flaws could lead to a buntover. Big difference.

[KenSandyEggo]

Hey Ron, don't worry about Shadow. If we ever meet up with him at some fly-in, we'll just sneak up behind him, dog-pile him and kick the **** out of him. Then we'll run away really fast. You do still work out at the gym, don'tcha, Ron? :p

[GyroRon]

Hey, we can just wait for him in the shadow. He won't see us coming! ;)

[Shadow]

. . . I hardly think my pre rotator getting loose will kill me. Could cause a emergency landing though, if the prop is damaged or the pre rotator is banging the bendix up into the ring gear. A RAF and it's flaws could lead to a buntover. Big difference.

if these break in flight who knows how bad it could turn into, it could go through the prop, could try to engage the pre rotator, etc

Ron, wouldn't that cause a sudden, unwelcome rapid loss of altitude? How would that differ from a PPO to the pilot. Wouldn't the result be the same?

the Halo would be shinny then. (hopefully)
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Don't worry about me Ken, I'm 68 but I still have my Back (velvet) Belt. :p
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[KenSandyEggo]

A lost prop would still allow one to glide down and dead-stick in. A PPO leads to the pilot BEING a dead stick. Many people have lost their prop in flight and survived. Haven't heard of anyone who survived a PPO.

Oh yeah? Well I'm much younger than you.....well.....4 years, O.K? And I have a brown belt. It's kind of shabby and the buckle is falling apart, but it still holds up my pants most of the time.

[Rotorhead]

Yep broke ( B box ) on my first dominator threw it on shelve haven’t missed with since if there is fix in the works. Please info me wasn't pleased at all with the way it worked.

[MikeBoyette]

Craig,
Did you get a new one or just totally quit flying your Dominator?

[Rotorhead]

Mike

I bought a side mount bracket from wunderlich went mechanical, I've since built a new frame with folding mast to accommodate my families camping needs also upgraded the
motor 582 E box 3 to 1 and will be able swing larger prop. It would be nice to
get some kind of use out, it's hard to explain to wife why I need new pre rotator.

I'm sure I did something wrong, but the factory could provide better work instructions pictures something other than colored electrical tape. Most us are out here operating all alone no one looking over our shoulders. you know what I mean !

Mike would you be interested in building me new mount for my new E box and if so how much ?


Thanks

[MikeBoyette]

Craig,
I don't work for my dad I just try to answer any questions on here I can. My dad doesn't like to post. I would suggest you give him a call. I don't think he's ever built a mout for an e-box not sure though. Give him a call @813-634-3370.

[BUD ONEAL]

Ernie Buys The Units Off The Shelf, He Has No Way Of Controling How They Are Cast.if He Did You Can Bet That There Would Be A Fix Ouick. He Is A Honorable Person And A Damn Good Man Also. I Am Proud To List Him As A Friend, Just My Nickles Worth.

[jdalexa]

Hey Ron,

You have any pix of the cracked part? I'll be checking mine tomorrow for sure. I wish there were some other Dominator drivers out this way to geek with.

[GyroRon]

No sorry, I didn't take any pics. Look the crack was EASY to spot, it wasn't hidden and won't be on your either. Just look for cracks and grab the pump and try to wiggle it, if it moves then you got a crack or a loose bolt somewhere.

Bud, I wasn't coming down on Ernie! I am sure he didn't expect there to be any problems, and not everyone is having problems. I am sure if the problems keep getitng worse he will redesign that piece. They have a 4 bolt pattern flange instead of the 2 bolt flange used now that would be easy to install. The 4 bolt flange looks much stronger to my eyes.

[BUD ONEAL]

Hold on Ron I never intended to come across as bashing you about Ernie, Just stateing my own true feelings about our friend, How is the little one doing?also not to leave out Shannon!

[GyroRon]

It's okay Bud, I knew what you meant. I just didn't want it to seem like I was dogging ole Ernie out.

Shannon and Kasey are doing good!

[robertstodaro]

I'm looking for the picture of my over-flange-fix-it ring.

I may have to make a hangar trip to take a new shot.

[GyroRon]

Yeap that is EXACTLY where mine cracked and in the same exact place as well... No new cracks as of yet though

[rehler]

Shadow, when discussing a failed prerotator/prop you stated: "wouldn't that cause a sudden, unwelcome rapid loss of altitude? How would that differ from a PPO to the pilot. Wouldn't the result be the same?"

This sounds like you have little experience with landing a gyro. It does not require any power to do so. Loosing an engine, prop, etc. only causes the pilot to land before he intended. I have had 6 such landing in gyros over many years and have never had a problem, other than having to walk a long way after I landed.

PPO on the other hand usually kills the pilot. Engine or prop failure in a gyro is the same as turning off your engine - similar to what you do every time you land.

And, all safe gyro pilots avoid flying over areas where they can not safely land.

[robertstodaro]

" I know RAF outsells most others, so that may be the reason for the focus on them, but... I know a Stock KB-3 has to be just as dangerous as far as buntovers go as any Stock RAF."

Somebody on this post said this and I think they'er most likely wrong.

If the kb3 isn't ctl, it's very close to it.

[GyroRon]

Robert, I said it. There is alot of power - for the light weight of the machine - and no stab and the thrust line IS several inches higher than the CG, perfect set up for a bunt over. I know at least one person that was killed when his KB-3 bunted over in front of other gyro pilot witness'

The KB-2 is a whole other story with the short prop VW and even shorter Mac.

[Doug Riley]

More than one KB-3 has PPOed. A redrive allows a bigger prop. The increased prop diameter means you have to move the centerline of the prop up. Unless the redrive offset is arranged to push the engine up above the prop centerline, you'll end up with a significantly high thrustline if you stick to Bensen-style low seating.

As for catastrophic consequences from prerotator failure: loss of engine power or even a prop will not, in themselves, cause a crash. However, a prop that breaks off or sheds blades creates some large pieces of high-speed shrapnel. Those pieces can (and probably will) take out parts/all of the rotor. They may also cut off the tail, which adds to the cloud of shrapnel. A hydraulic pump that comes loose is significant piece of metal to have flopping around a fraction of an inch from the prop. The potential for deadly damage is clear. It's not a situation to be taken lightly.

In general, the presence of both a pusher prop and a rotor makes the aircraft very unforgiving of junk coming loose -- even if the falling-off junk wasn't that important in itself. Example: Ken Brock was injured once by his little drift flag. It came loose, blew back into the prop and got slingshotted forward again, penetrating the seat tank and impaling Ken in the back.

Moral: Secure everything VERY carefully, and secure the really scary items by redundant means.

[Chuck Roberg]

I have had two different KB-3s. And yes they definitely will PPO. I have flown them in 25-30 mph winds. And it's like riding on a rocking horse.

It's fun to go up and play in the wind. But after about 20-30 minutes in the KB-3 I would have enough and come back down.

I would only fly around the airport in that kind of wind. I would never think of trying x-country. I would also throttle back and never go over 50mph in that kind of wind.

[robertstodaro]

Hang the engine plugs up and put a stab on them things boys. All mine were much nicer after I did that.

back the the subject: I had an aluminum ring turned down to fit my pump base and and then back drilled it with the oringial mount holes. It clamps the pump base down to the mount plate all the way around. No problems in the last 60hrs except for a sticky belt and I just ordered 3 today.