What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

Zip Ties on engine mounts, don't do it!

Status
Not open for further replies.

Russ McCutcheon

Well Known Member
Ok guys maybe this has been covered before. I just did some repair work on an old early 80s RV-4 engine mount, the right tube that comes up from the top of the gear leg socket to the bottom of the engine was broken thru and had all the paint polished off, it had absolutely no deformation, not flexing or bent, the same tube on the other side was cracked also, about 2" above the weld, well out of the heat affected zone, right where a zip tie had worn thru the paint and you could see it had abraded the tube right where the crack had formed, the surface of the tube looked like it had been work hardened promoting the crack.

My old -4 has a bunch of zip ties on the engine mount too, I will be inspecting and eliminating these before further flight!
 
I used only blue Tefzel zip ties FWF. Mainly I used Adel clamps on the engine mount to support wiring. But when I used a zip tie I wrapped the mount with self fusing silicon Rescue Tape. You will see that I also used it on the wire to stop the zip tie chewing through the wire insulation.

 
Thanks Russ

I am glad you started this thread, because I was going to start this exact thread tomorrow. I am helping John the owner of the 1986 RV4 that you are referring to. I was very surprised to see the tie wrap on top of the crack. It was tight and did not seem to be vibrating or moving that much. I will immedately inspect mine now and replace with either anti chaffe tape underneath the tie wraps or use adel clamps. I will also inform all the RV owners that I know of the problem. I believe that that the subject plane only has a little over 1000 hours on it.


Steve Barnes "The Builders Coach"
 
Great Safety Topic

Thread moved from 'RV General Discussion/News' to 'Safety'.

I've seen many engine installations on RV's and my personal observation is that the majority of builders use tie wraps to secure wire/other to their engine mount. I'll admit that I was sceptical of the tie wrap cutting through the engine mount until I saw one with my own eyes. Thanks for starting the thread, I hope folks take another look at their installs and make corrections if/where needed.

I'll put my Oshkosh Judges hat on for a moment, for those displaying their hard work for the Judges at Oshkosh.....you WILL get a deduction for using tie wraps on your engine mounts.

Bill R's pics show a nice alternative to tie wraps and some very clever use of adel clamps. I'm sure he knows there are still a few tie wraps on his install but I'll bet they'll be replaced with clamps the next time his cowls come off. Thanks for sharing your pics Bill!




I'm a BIG fan of using Adel clamps as you can see in these pictures;
 
I'll put my Oshkosh Judges hat on for a moment, for those displaying their hard work for the Judges at Oshkosh.....you WILL get a deduction for using tie wraps on your engine mounts.

I used quite a few tie wraps when I built the plane. First year at OSH I was there when several judges were looking at my plane and I overheard them discussing the tie wraps. Over the last several years, during my conditional inspection, I have change over the tie wraps to adel (not the singer) clamps, switch the ones on the engine mounts first. I now have no tie wraps and it looks great and no worries of inspecting under the tie wraps every year. Big help was getting a good tool. They are a snap to put in with this.
 
Last edited:
Not new news, although important.

This is Not new, although is important for long term success.

I have heard of this being a problem for years from A&P mechanics with General Aviation aircraft owners.

A&P's have told me Adel Clamps are the best way to attach if used on the engine mount tubing, if at all possible. If not possible another chafe/protection should be used.
 
...Bill R's pics show a nice alternative to tie wraps and some very clever use of adel clamps. I'm sure he knows there are still a few tie wraps on his install but I'll bet they'll be replaced with clamps the next time his cowls come off. Thanks for sharing your pics Bill!

You are correct Rick about replacing those zip ties. Those are old pictures of the O-290-D2 installation and when I replaced that engine and engine mount the zip-ties came out. I used more lace cord and adel clamps with the new installation.

While I was given some grief about the number of Adel clamps I used, when I removed the old engine mount, there were no signs of chafing or rubbing after 250+ hours.

The only place that I can think of that still has zip-ties is under the cylinders where high-temp ties were used to keep the cylinder head temperature probe leads from rubbing against the intake runners. Until I can think of a better solution under there, they will remain.
 
Last edited:
You also have to keep an eye on Adel clampls, the rubber gets soft and twisted out of position, they deteriorate from heat and oil and the rubber will extrude itself from the clamp over time.

I know Adels are the "standard", but I actually prefer silicon uni-wrap tape, sleeving and lace cord for the ultimate protection. If you do it right it can also look good :D
 
Russ,
Does the owner know how many operational hours the zip ties have been in place on the mount? Is this a case of the zip ties being in place since the plane was built?
 
I really like having Adel clamps, but there are places in very tight engine compartments where it is just impossible to fit a doubled clamp and get the tools in there to fasten them. In that case, I use a rubber or silicon tape to protect the engine mount tube, and carefully-trimmed zip ties.

Remember the old saying - there are NO absolutes!! :)
 
I used both methods...alt/starter cables, fuel/oil lines should always get clamps. The remaining wiring got a little of each, depending on ease of access/clearances. I also like Walt used orange silicone tape from Spruce beneath tefzel and halar ties. My family hauler as most won't be entered in any shows. Take a look at some brand new $300,000+ certifieds and you will see a little of both too.
 
Russ,
Does the owner know how many operational hours the zip ties have been in place on the mount? Is this a case of the zip ties being in place since the plane was built?
Steve Barns is helping/doing the repairs to this airplane and this is what he said in post #8, it's more information then I had.

""""I am glad you started this thread, because I was going to start this exact thread tomorrow. I am helping John the owner of the 1986 RV4 that you are referring to. I was very surprised to see the tie wrap on top of the crack. It was tight and did not seem to be vibrating or moving that much. I will immedately inspect mine now and replace with either anti chaffe tape underneath the tie wraps or use adel clamps. I will also inform all the RV owners that I know of the problem. I believe that that the subject plane only has a little over 1000 hours on it"""".


Steve Barnes "The Builders Coach"
 
Pictures please!!

Do you have any pictures of the cracks. One tube is cracked/"polished" with the other cracked/"workhardened by a plastic wire tie".

I have talked to major motor mount rebuilders in the past and they say engine contol cables and scat tube tied directly to the mount are the most common problems with cable ties causing rub throughs. Not the tie itself, but the part tied against the mount causing the damage.

Will a plastic tie actually saw thru a chromemoly tube?

Sounds like an old wives tail. Sitting a battery on concrete will "drain" it and never cross rotate radial tires are a couple that still survive from the distant past.

I am not saying it can not happen and that good security paractices should not be used, but would like to see it for myself.

George Meketa
 
No pictures here. It did not cut through the tube, it damaged the surface of the tube and the tube cracked, one was broke all the way off and the other was cracked part way through. believe it or don't.
Do you have any pictures of the cracks. One tube is cracked/"polished" with the other cracked/"workhardened by a plastic wire tie".

I have talked to major motor mount rebuilders in the past and they say engine contol cables and scat tube tied directly to the mount are the most common problems with cable ties causing rub throughs. Not the tie itself, but the part tied against the mount causing the damage.

Will a plastic tie actually saw thru a chromemoly tube?

Sounds like an old wives tail. Sitting a battery on concrete will "drain" it and never cross rotate radial tires are a couple that still survive from the distant past.

I am not saying it can not happen and that good security paractices should not be used, but would like to see it for myself.

George Meketa
 
I'm from Missouri so Show Me

Do you have any pictures of the cracks.....
Will a plastic tie actually saw thru a chromemoly tube?.Sounds like an old wives tail....but would like to see it for myself. George Meketa
In February of last year, a poster said he was told by at least one judge at Oshkosh that zip ties located FWF was against FAA regs. I refer the interested to post #60 found on this thread:

http://www.vansairforce.com/community/showthread.php?t=52559&highlight=zip+ties

I think the ridiculousness of that line of reasoning was sufficiently challenged. Later that year, I made it a point to photograph one FWF installation on a brand new certified aircraft on display at AirVenture 2011 and zip ties were there for all to see. Nevertheless, this topic points towards an unreasonable bias that continues to perpetuate.

Now the thinking seems more focused upon zip ties that are actually attached to the engine mount. I know what I know. I personally removed at least a dozen or more zip ties from the engine mount on my old C150 that were known to be in place for at least the 18+ years I owned the plane. Those zip ties didn't even wear through the paint. Now if you closely examine the image on this link to a Plane and Pilot article on a FWF restoration, you will see liberal use of zip ties including some directly attached to the engine mount:

http://www.planeandpilotmag.com/aircraft/maintenance/upgrade-your-plane-part-iii.html

There has been a long, long time request for pictures of damage caused by zip ties but conclusive, indisputable proof of "a plastic tie actually sawing through chromoly tube" seems as elusive as Bigfoot.

Mythbusters once proved a prisoner can't saw through prison bars using dental floss no matter how much Herculean effort put into it.

I'm with you George. Show me the proof. Like you, age and experience has taught me that that there are exceptions to every rule but on the whole, zip tie hysteria sure sounds like an old wives tale to me too.
 
In February of last year, a poster said he was told by at least one judge at Oshkosh that zip ties located FWF was against FAA regs. I refer the interested to post #60 found on this thread:

http://www.vansairforce.com/community/showthread.php?t=52559&highlight=zip+ties

I think the ridiculousness of that line of reasoning was sufficiently challenged. Later that year, I made it a point to photograph one FWF installation on a brand new certified aircraft on display at AirVenture 2011 and zip ties were there for all to see. Nevertheless, this topic points towards an unreasonable bias that continues to perpetuate.

Now the thinking seems more focused upon zip ties that are actually attached to the engine mount. I know what I know. I personally removed at least a dozen or more zip ties from the engine mount on my old C150 that were known to be in place for at least the 18+ years I owned the plane. Those zip ties didn't even wear through the paint. Now if you closely examine the image on this link to a Plane and Pilot article on a FWF restoration, you will see liberal use of zip ties including some directly attached to the engine mount:

http://www.planeandpilotmag.com/aircraft/maintenance/upgrade-your-plane-part-iii.html

There has been a long, long time request for pictures of damage caused by zip ties but conclusive, indisputable proof of "a plastic tie actually sawing through chromoly tube" seems as elusive as Bigfoot.

Mythbusters once proved a prisoner can't saw through prison bars using dental floss no matter how much Herculean effort put into it.

I'm with you George. Show me the proof. Like you, age and experience has taught me that that there are exceptions to every rule but on the whole, zip tie hysteria sure sounds like an old wives tale to me too.

agree! 15 years with zip ties on my BD-4 engine mount painted with a cheap primer (not powder coated) and not one of those suckers cut through the paint - ever!

The theory seems to be that grit & grime will get under the zip tie and wear the steal away... seems to me the softer material would wear away and break long before the steal.
 
snipped
I know Adels are the "standard", but I actually prefer silicon uni-wrap tape, sleeving and lace cord for the ultimate protection. If you do it right it can also look good :D

Walt,
Would you mind posting a photo or two of your method mentioned above to this thread? I always like to learn new tricks.
Charlie
 
Cheap rubber.

On engine mount with zip ties, I placed a piece of rubber from a bicycle inter tube between the mount and the ties. It works well.

Kent
 
Do what you want

I never said it sawed through the tube! And something these structures have that jail bars don?t have is vibration cycles under stress, you don?t have to saw through it all you have to do is damage the surface then the stress and vibration will do the rest. My 29 year old RV-4 does show some zip ties that have worn through the paint.
Not making any statement of what is legal or not, I don?t know, just trying to give you guys a heads up about what we found on this engine mount.

In February of last year, a poster said he was told by at least one judge at Oshkosh that zip ties located FWF was against FAA regs. I refer the interested to post #60 found on this thread:

http://www.vansairforce.com/community/showthread.php?t=52559&highlight=zip+ties

I think the ridiculousness of that line of reasoning was sufficiently challenged. Later that year, I made it a point to photograph one FWF installation on a brand new certified aircraft on display at AirVenture 2011 and zip ties were there for all to see. Nevertheless, this topic points towards an unreasonable bias that continues to perpetuate.

Now the thinking seems more focused upon zip ties that are actually attached to the engine mount. I know what I know. I personally removed at least a dozen or more zip ties from the engine mount on my old C150 that were known to be in place for at least the 18+ years I owned the plane. Those zip ties didn't even wear through the paint. Now if you closely examine the image on this link to a Plane and Pilot article on a FWF restoration, you will see liberal use of zip ties including some directly attached to the engine mount:

http://www.planeandpilotmag.com/aircraft/maintenance/upgrade-your-plane-part-iii.html

There has been a long, long time request for pictures of damage caused by zip ties but conclusive, indisputable proof of "a plastic tie actually sawing through chromoly tube" seems as elusive as Bigfoot.

Mythbusters once proved a prisoner can't saw through prison bars using dental floss no matter how much Herculean effort put into it.

I'm with you George. Show me the proof. Like you, age and experience has taught me that that there are exceptions to every rule but on the whole, zip tie hysteria sure sounds like an old wives tale to me too.
 
Status
Not open for further replies.
Back
Top