Vacation and gear issues

"should I reset the breaker and let it build the pressure as you mentioned then pull if the pump continues to run? "

I would (make sure the e dump is up) then make the short trip with the gear down. Do you have a gear motor run light?
 
Start by turning the master switch on and listening to see if the pump runs. If the pump doesn't run continuously then there's no need to do anything. Take off with the gear down. Fly it to where you want to go and land. Pulling the breaker and all of the other things suggested are great suggestions, but only if the pump is continuously running and you want to keep it from burning out.
Years back I took off from an airport- I think it was Monroe and my gear wouldn't come up. I knew there wasn't a lot of services at that airport so I just flew it with the gear down to get to another airport with services (I think it was Little Rock ). Just don't expect
breakneck speeds and watch your temperatures.
 
David Price said:
"should I reset the breaker and let it build the pressure as you mentioned then pull if the pump continues to run? "

I would (make sure the e dump is up) then make the short trip with the gear down. Do you have a gear motor run light?
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David,

That's the plan. check the E dump to make sure it is up, then cycle the breaker to see if the pump runs continuous, if not, I'll leave it in. I do not have a gear motor light but it will be on my annual list "to do" for June.

I'll update the thread with the findings upon return from the shop on Thursday.
 
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I went over to the hangar and did some quick checks. First I checked for leaks, found no hydraulic anywhere. I did not take the rear floor pan off, I’ll do that Thursday at the shop. Next I checked the fluid level in the pump, I had to add eight to ten oz. Hmm, where did that go?

Next I climbed in and confirmed the E dump was up and secure. I then confirmed my breaker is in and with that flipped the battery switch and listened. Instead of the quick pump “zip” the pump ran a couple of seconds ending with that “zip”. Pump shut off and everything seemed normal. I putzed around the hangar cleaning up and installing cowl plugs and plugging in my tug. I climbed back aboard and went battery on with no pump running. Good enough to get me to the shop just ten minutes away.

I’ll update again when I fly home from the shop.
 
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If we are taking bets, I say you will find nothing wrong, except maybe a microswitch that although working now could use a very small adjustment.
 
gmascelli said:
I went over to the hangar and did some quick checks. First I checked for leaks, found no hydraulic anywhere. I did not take the rear floor pan off, I’ll do that Thursday at the shop. Next I checked the fluid level in the pump, I had to add eight to ten oz. Hmm, where did that go?

Next I climbed in and confirmed the E dump was up and secure. I then confirmed my breaker is in and with that flipped the battery switch and listened. Instead of the quick pump “zip” the pump ran a couple of seconds ending with that “zip”. Pump shut off and everything seemed normal. I putzed around the hangar cleaning up and installing cowl plugs and plugging in my tug. I climbed back aboard and went battery on with no pump running. Good enough to get me to the shop just ten minutes away.

I’ll update again when I fly home from the shop.
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Gary,

If you have used the e-dump either for real or for test extensions, the process of the gear coming down "abruptly" will cause some 5606 to puke from the vent hole in the pump reservoir. That fluid runs down the pump body/mounting bracket and ends up in the belly of the plane. Creates a sticky trail that dries along the way so you are not likely to find a puddle in the belly. That could account for your "missing" fluid. The closer to Full the reservoir, the greater the amount of fluid that pukes out of the vent. For this reason, when planning to test the e-dump during annual or for planned airborne tests, it is a good practice to wrap the pump reservoir with some absorbent shop towels to catch the mess before it runs down the inside of the fuselage. ...and then remember that the reservoir will no longer appear "Full". (will still operate just fine)
 
One additional item,... during your troubleshooting, it might be a good idea to exercise the e-dump valve to reseat the o-rings in case a mis-seat might be allowing some bypass. Of course, it will make less mess if you do this with the gear already extended. When finished and with the e-dump open, flush the seat and rings by selecting gear up for 5-10 seconds to run the pump before selecting gear down again and then closing the e-dump valve with the pump shut down. Never a good idea to close the e-dump with the pump running. good way to damage the o-rings.
 
Bill, as always great info, thank you.

I went back over this morning to give everything another look and found no trace of hydraulic fluid. I’ll pull the back floor Thursday. Not even anything on the belly or any of the drain holes. The pump and surrounding area is spotless too.

The E dump was returned to up and in position with the pump off so that should be good to go.
 
I just returned from the shop and I have to say this one is a real head scratcher. First, a fluid level check on the pump, it was good. Next with the use of an extended mirror we found no leaks, however the one AN connection needed about a quarter turn. We did find some residue but it was negligible, considering the amount of 5606 I had added to the system the day before. OK, where did it all go?

The shop cycled the gear multiple times and maybe the first two we could hear air in the system. By the third cycle everything seemed normal. We left the gear up and shut everything down to see if there was any leak down. While we let the gear sit the rear floor was removed and everything checked, including each fitting. Everything was tight and no leaks found. We powered back up and heard an abbreviated zip, really quick, just a blip. Next we cycled the gear another half dozen times monitoring the rear floor compartment and another look with the mirror to check the pump itself. All Clear.

Each gear well was inspected along with the actuators and all lines and connections. Again everything was clean and dry, no leaks. Here are a few pictures of below the rear floor and the connections at the pump. My best guess is that the the pump fluid level was not checked the last two annuals. I watched my May 2021 annual including the gear swing and E dump, then refilling of the pump reservoir. I did not watch the gear swing at the new shop the last two annuals. You can bet I will watch this year just to see the procedure.

gear service 3 v1.jpggear service 1.jpggear service 2.jpg
 
The quick zip to pressurize the system when you first start up is not unusual. What is unusual is your comments that there was air in the lines. If that's the case, there has to be some kind of an internal leak as those lines should always be 100% fluid. The system is self-purging and will remove the air but it shouldn't be there in the first place.
 
Commander91gm said:
The quick zip to pressurize the system when you first start up is not unusual. What is unusual is your comments that there was air in the lines. If that's the case, there has to be some kind of an internal leak as those lines should always be 100% fluid. The system is self-purging and will remove the air but it shouldn't be there in the first place.
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I think my fluid level was so low that the pump kept running trying to move the gear until I pulled the breaker and performed an E dump. Once home from vacation (driving) I did add eight to ten oz of 5606 to just shy of the threads on the fill. After going over everything today the gear swing is back to normal and the pump run is about 8 seconds on the down and maybe 10-12 up.
 
I read the thread.

This is what i have to say (from someone who's had to use E-Dump in anger at least 4 times).

- Pull the THROTTLE back before pulling e-dump valve. Even though book says 75 KIAS for e-Dump - its the prop wash (as Joel said). You can do it around 100 KIAS so long as you pull power back. Else the nose will not lock.

- if it DOESN't lock - then before doing any gyrations - again pull the throttle all the way back and take it to < 85 KIAS. The nose wheel will lock if you take the prop wash or airspeed generated force off it.

If you have NEW springs - the e-dump witll work with even the throttle in and 100 KIAS. As the springs get older - the Throttle needs to come back.
The spring force is no longer great enough to overcome the opposing force of the prop wash.

My first e-dump in 2005 : Throttle at 32 inches - 100 KIAS - E-DUMP and boom - the gear deployed.

My second e-dump in 2015 : Throttle at 32 inches 100 KIAS and the nosewheel didnt lock. It finally locked around 82 KIAS when i pulled the power back.

My third e-dump in 2015 - throttle at 30 inches 100 KIAS and the nosewheel didnt lock. It locked around 75 KIAS - when i pulled the power back

My Fourth e-dump in 2018 or 2019 - throttle back - under 100 KIAS and boom - deployed first time.

IN 2020 - i refreshed all the springs.



The book calls for 75 KIAS for e-dump.
 
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Moazzam, I have a brand-new nose gear spring and it does make a difference for sure on the way it locks. I've done some e-dumps and I my locked right around 90 KIAS. How about the mains??? Is it necessary? I mean, it's always good to have new springs, but is the critical one the nose?
 
Hopefully you have two brand new nose gear springs since one sits inside the other :)
 
The mains are pure gravity. They’re so heavy they always just lock. The nose gear coming down is fighting drag (airspeed) as well as prop wash and has to overcome that collective force to lock. It will come down but won’t lock if the drag force exceeds gravity and spring assist. Removing the prop wash removes most of the opposing force. Then anything less than 100 KIAS works. Once it’s already down and hanging and not locked, now you’ll have to reduce both airspeed and chop the power to get it to lock ..
 
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