Retractable step problem

[ELT]

The vacuum operated step on my Ë quit retracting.  I cleaned and lubed it to no success.  Next I replaced the tape and checked the boot.  Now the step goes up about half.  Vacuum pressure at the pump is good.  Any suggestions as the Mooney service instruction are a bit thin?  Is there any adjustment and how far should the boot be up on the servo? 

Thanks,

Eddie

[rbridges]

what did you lube the step with?  You need to use something thin.  The service manual recommends a teflon lube.  I was using lithium grease, and it was gumming up the step.  

[Bob_Belville]

I think that servo (boot) should have plenty of power... unless it has a leak. I would double check the rubber for cracks unless you know it has been replaced in recent years. Apparently the useful life of that rubber is something less than 50 years based on the number of folks reporting problems in the last few years. They just don't make stuff like they used to in the old days.

 

Have you had someone observe the servo with the battery door off and the engine running? Is the cable hanging up or it there a vacuum wheeze? Chock the wheels and lock the brakes 'cause you may need a little more than idle rpm to hold full scale vacuum.

[ELT]

Thanks.  I used triflow.  Have not had anyone (my wife has been assisting) willing to stick their hair in the prop wash. The boot looks good and has no bad spots.   I think I will wipe and lightly sand some spots on the step and lube again.

Eddie

[N601RX]

Thick grease keep it from coming down, but is unlikely to keep it from going up.  Some of the cracks and splits are difficult to see until they are bent just right and open up. The leak could also be in the hose going up to the panel.  It hooks in on the back of one of the instruments, I don't remember which one. If it is a leak, it is letting unfiltered air into your vac system. The easiest way I have found to deal with these and other PC leaks is to buy a small handheld vac pump with gauge on it from an auto parts store. You can connect to different points in the system and quickly find the leaks.

[rbridges]

Thick grease keep it from coming down, but is unlikely to keep it from going up.  

 

 

true.  my problem was it hanging up when I turned the engine off.  

 

have you tried pulling the step up manually to see if it binds anywhere?

[smwash02]

Have you considered a split in the vacuum line to the step?

 

What kind of suction are you getting on the end?

[carusoam]

Tell how you get the wife to help out!!!

I thought things were good when she didn't mention the spending...

This Could be a new definition for "keeper"!

Best regards,

-a-

[ELT]

I will recheck the boot and if not that go after the lines.  Keeper. Yes, met her 42 years ago.  She had just got her PPL on her 17th birthday.

[Steve65E-NC]

A hand vacumn pump used to check automotive vacumn systems is invaluable (harbor freight around $28, you will have to come up with appropriate barb fittings (Ace Hdw))

With the pump, you can check each servo and step bellows over full range with engine off. Once I found a sheet metal screw through a green or red tube in the rear of the cabin.

I think silicon spray is the only recommended lube for the step shaft.

Careful that a big step leak may affect vacumn nav instrument performance. I think the feed for the step comes right off the back of the AH so this can cause a slow AH without showing on vac gauge.

[rbridges]

A hand vacumn pump used to check automotive vacumn systems is invaluable (harbor freight around $28, you will have to come up with appropriate barb fittings (Ace Hdw))

With the pump, you can check each servo and step bellows over full range with engine off. Once I found a sheet metal screw through a green or red tube in the rear of the cabin.

I think silicon spray is the only recommended lube for the step shaft.

Careful that a big step leak may affect vacumn nav instrument performance. I think the feed for the step comes right off the back of the AH so this can cause a slow AH without showing on vac gauge.

 

I'm going by memory, but I believe the maintenance manual recommends triflow (sp?) which is a teflon spray.

[DrBill]

My step hangs up sometimes and I find the step itserf binds on the rubber gasket between the strep and the bottom panel

 

BILL

[rockydoc]

Maybe one of you can help me find out why my M20B manual step will not stay in the fully retracted position since my AP replaced the cable at annual.  It drops down about 10-20% after I retract it.

[N201MKTurbo]

So here is something to try on your step.

I had an M20F for 19 years, but it never had a step. So I never tried this.

My dad was a great carpenter. He told me to use paraffin wax to lube and protect my tools. Just rub a block of wax on the metal parts, work them together a bit then rub the excess off with a rag. It makes things slide real easy, lasts a long time and keeps it from rusting.

[Bob_Belville]

So here is something to try on your step.

I had an M20F for 19 years, but it never had a step. So I never tried this.

My dad was a great carpenter. He told me to use paraffin wax to lube and protect my tools. Just rub a block of wax on the metal parts, work them together a bit then rub the excess off with a rag. It makes things slide real easy, lasts a long time and keeps it from rusting.

As a beekeeper I can vouch for beeswax as a lubricant in certain applications. I use in on seat tracks.

[rockydoc]

My problem is that when I crank the step up, it won't stay up for long.  It slowly lowers itself so that it is down about 10-20%.  This is a pain when flying because i can't seem to remember to keep craking it back up.  HELP!

[scottfromiowa]

So here is something to try on your step.

I had an M20F for 19 years, but it never had a step. So I never tried this.

My dad was a great carpenter. He told me to use paraffin wax to lube and protect my tools. Just rub a block of wax on the metal parts, work them together a bit then rub the excess off with a rag. It makes things slide real easy, lasts a long time and keeps it from rusting.

I used to do this on my blade sled runners....Awesome.

[DaV8or]

I think you can check the vacuum step servo by disconnecting the vacuum line and plugging it, then push the step up manually and if there is any leaks in the bellows, you can either hear them, feel them, or find them with soapy water.

 

Don't you wish we could all have electric steps? I do.

[scottfromiowa]

I think you can check the vacuum step servo by disconnecting the vacuum line and plugging it, then push the step up manually and if there is any leaks in the bellows, you can either hear them, feel them, or find them with soapy water.

 

Don't you wish we could all have electric steps? I do.

His is not pneumatic Dave. It is the manual crank retraction variety. No clue on how to "fix" the slipping step. Take a look at the service manual to see if any components can be replaced?

[DaV8or]

His is not pneumatic Dave. It is the manual crank retraction variety. No clue on how to "fix" the slipping step. Take a look at the service manual to see if any components can be replaced?

 

Actually, there are two guys in this thread having an issue. The OP does have the vacuum operated step and then another guy came asking about his crank step. I was responding to the OP. I don't know anything about the crank step, but I imagine there must be a way to either adjust the friction on the crank itself, or possibly if there is any kind of spring that assists the retraction of the step, adjust that to have more tension. Again though, I know nothing of that system.

[Wildhorsesracing]

My problem is that when I crank the step up, it won't stay up for long.  It slowly lowers itself so that it is down about 10-20%.  This is a pain when flying because i can't seem to remember to keep craking it back up.  HELP!

 

Does the hand crank move 10-20%?

[rockydoc]

Does the hand crank move 10-20%?

Yes, the crank rotates counter clock wise approx 120 degrees.