Lock nuts v. castle nuts on engine mount?

rcfaubion · #1 12-08-2009, 05:08 PM

My two lower rubber mounts, ( RV-4 0-320 160 hp) were backwards so removed and installed correctly (I needed the slight raise of the nose anyway), had to loosen the top two also. The bolts showed very slight signs of being a little loose, is anyone using metal locknuts as opposed to pinned castle nuts to ensure a proper tightening, and should I even consider this?

Thanks,

Martin Sutter · #2 12-08-2009, 05:25 PM

I have been using steel lock nuts on the engine mount bolts on my RVs for years. I check the torque regularly when I have the cowl off and have never found any of them loose. Using steel lock nuts also eliminated the @#%&* cotter pins wich are so hard to install and remove on the bottom mounts.

Martin Sutter
building and flying RV's since 1988
EAA Technical Counselor

Vlad · #3 12-08-2009, 06:15 PM

I had an opportunity to see nice RV at Oshkosh this year. The owner was A&P and had all other titles. He gave us visitors excellent explanations of everything seemingly unusual on his aircraft.
Nuts on engine mounts were one of those unusual things. Also bolts attaching the mount to the firewall were inserted in reverse to our plans and locknuts were inside the cabin.

az_gila · #4 12-08-2009, 06:58 PM

Quote:

Originally Posted by Martin Sutter

I have been using steel lock nuts on the engine mount bolts on my RVs for years. I check the torque regularly when I have the cowl off and have never found any of them loose. Using steel lock nuts also eliminated the @#%&* cotter pins wich are so hard to install and remove on the bottom mounts.

Martin Sutter
building and flying RV's since 1988
EAA Technical Counselor

...Tiger uses steel locknuts on the engine mount bolts and, like Martin says, no @#%&* cotter pins to play around with.

Geico266 · #5 12-08-2009, 07:38 PM

Quote:

Originally Posted by az_gila

...Tiger uses steel locknuts on the engine mount bolts and, like Martin says, no @#%&* cotter pins to play around with.

I'll bet Tiger wished he had something to play with now.

Danny7 · #6 12-08-2009, 08:35 PM

boy, everyone is a comedian tonight!

break

Vlad (or anyone that knows) what is that red tie rod in the photo? is it a brace for the baffle? I can't figure out how it would control anything. It goes from the centerline of the engine back to the photo right baffling.

another question- does toque seal work in an engine bay? would you put some on those lock nuts?

L.Adamson · #7 12-08-2009, 08:47 PM

Quote:

Originally Posted by Danny7

boy, everyone is a comedian tonight!

break

Vlad (or anyone that knows) what is that red tie rod in the photo? is it a brace for the baffle? I can't figure out how it would control anything. It goes from the centerline of the engine back to the photo right baffling.

It's a brace for the weight of the cooler on the backside of the baffle. I have one in the same location.

L.Adamson --- RV6A

Greg Arehart · #8 12-08-2009, 08:51 PM

I put torque seal on a lot of things around (not directly on) the engine, and so far no problem. Seems to work ok for at least a year's worth of flying.

greg

Vlad · #9 12-09-2009, 05:22 AM

Quote:

Originally Posted by Danny7

boy, everyone is a comedian tonight!

break

Vlad (or anyone that knows) what is that red tie rod in the photo? is it a brace for the baffle? I can't figure out how it would control anything. It goes from the centerline of the engine back to the photo right baffling.

another question- does toque seal work in an engine bay? would you put some on those lock nuts?

Yep, what Larry said.

az_gila · #10 12-09-2009, 10:44 AM

Quote:

Originally Posted by Greg Arehart

I put torque seal on a lot of things around (not directly on) the engine, and so far no problem. Seems to work ok for at least a year's worth of flying.

greg

...torque seal on their case bolts and other hardware, and then spray the whole engine grey, right over the bolt heads and nuts...

The torque seal seems to live happily under the grey paint...