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Securing wires/hoses fwf

Draker

Well Known Member
Looking for opinions on a few FWF items I've been working on lately:

1. Securing wires and hoses. I've opted to use adel clamps attached to the engine mount to make sure that my wires and manifold pressure hose stay put. Is it recommended to use one clamp for wires and a different clamp for hoses? Or is it acceptable to bundle them together:



2. Securing starter and alternator wiring. I routed both the alternator B lead wire and starter power wire forward along the right side of the engine. A scrap seat belt anchor fit perfectly to make a bracket to secure that wire bundle. I used what appear to be an unused 5/16-18 threaded hole just above the air intake. Question: Is this really unused and free for me to abuse in this way?



3. Does anyone have any pictures of how they secured and routed their starter power wire? Im having trouble doing so in a way that doesn't put a tight bend in the wire.
 
FWF

Adel clamps are better than zip ties for sure. I separate fluid hoses and wires to avoid potential chaffing.

Consider not using any nylon locknuts in the high heat environment of the engine compartment, I’m not sure if you have them or not...

Here’s my alternator wires after 627 hours while doing some recent maintenance, notice adel clamps that go on the engine sump bolts.
 

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Consider not using any nylon locknuts in the high heat environment of the engine compartment, I’m not sure if you have them or not...

You're not the first person who looked at my engine compartment and suggested this. I'll have to strongly consider it. We're talking about AN363 all-metal stop nuts as a replacement part, correct?
 
Great zip ties but...

https://www.amazon.com/Rubber-Relea...t=&hvlocphy=9031979&hvtargid=pla-707844982240

These work awesome. They are reusable zip ties that have a rubber coating so they do not hurt wires or hoses with vibration. Mike Patey talked about them in one of his videos. I bought a pack and they are awesome.

I’ve used these excellent zip ties in the engine compartment. They soften a lot when they get hot. Replace them every oil change if they are in a high heat environment.
 
Metal stop nuts

You're not the first person who looked at my engine compartment and suggested this. I'll have to strongly consider it. We're talking about AN363 all-metal stop nuts as a replacement part, correct?

Metal lock nuts are cheap, I’m not sure why it took me so long to start using them.
 
You're not the first person who looked at my engine compartment and suggested this. I'll have to strongly consider it. We're talking about AN363 all-metal stop nuts as a replacement part, correct?

The reason is that the nylon insert is only good to 250*. Not saying that it's going to be catastrophic is you use them on an adel clamp or two, but don't be surprised if they loose their locking feature over time if you use them where it gets hot.
 
You're not the first person who looked at my engine compartment and suggested this. I'll have to strongly consider it. We're talking about AN363 all-metal stop nuts as a replacement part, correct?

I have heard this too, and I have installed metal locknuts starting at the firewall. But then I found several nylon locknuts that were installed by the engine manufacturer, and Vans calls for several in the FWF plans.
 
Braided hose and wiring do not belong together - the hose is extremely abraisive and will eat through the wiring insulation in no time. If its a high power wire on a flamable liquid hose, expect a flash and a fire when it shorts to the overbraid.

Your "seat belt" anchor clamp looks to be flat stock and cantelevered way out from the bolt. Id expect that to flex quite a bit and fatigue in short order - It will likely be cracked or broken off one of these days.

As others have mentioned, starter cables can use adel clamps on the left side oil sump rail bolts. Its usually a staight shot and keeps it out of the way.
 
Take a look at the OP31 drawing for the starter wiring routing. Use metal tabs (sold by Vans) to attach to oil pan bolts.
 
Seat belt hardware

I am leery of using the seat belt anchor to cantilever anything. Being super strong, I am concern the anchor will leverage the securing bolt and surrounding metal and cause damage to the supporting screw and material. I think one would want a bracket with some give, or at least be of a material that is the same toughness, as the mounting material. I just have a picture of the seatbelt anchor acting like a screwdriver in a 8 year old’s hand.
 
Question, not a criticism

Re: Second posting. Lite weight lines, wires on the push rod tubes = probably benign. A control cable that imparts some transverse load = probably should find another way. A fairly rigid mounting plate between two tubes probably adds another layer of “should find a better way”. Probably no danger to flight but the tubes should be allowed to float per design.

Just an opinion/observation. As mentioned, not intended as a criticism.
 
Thanks for the tips, everyone!

The reason is that the nylon insert is only good to 250*. Not saying that it's going to be catastrophic is you use them on an adel clamp or two, but don't be surprised if they loose their locking feature over time if you use them where it gets hot.

Makes sense, I'm convinced. Will grab a bag of these from Spruce next time I do an order.

Braided hose and wiring do not belong together - the hose is extremely abraisive and will eat through the wiring insulation in no time. If its a high power wire on a flamable liquid hose, expect a flash and a fire when it shorts to the overbraid.

I thought about this too, but the wires do not contact the metal braid. The hose itself is insulated with plastic, presumably to avoid chafing everything nearby.

Your "seat belt" anchor clamp looks to be flat stock and cantelevered way out from the bolt. Id expect that to flex quite a bit and fatigue in short order - It will likely be cracked or broken off one of these days.
I am leery of using the seat belt anchor to cantilever anything. Being super strong, I am concern the anchor will leverage the securing bolt and surrounding metal and cause damage to the supporting screw and material.

Yes it flexes quite a bit. After these comments and sleeping on it I've decided to redo and go find a better way.

Take a look at the OP31 drawing for the starter wiring routing. Use metal tabs (sold by Vans) to attach to oil pan bolts.

Could you point me to these tabs? Not sure what these are.
 
I used Adel clamps wherever possible, but when you have just a few wires to secure to the engine mount, wrap the tube with silicone rescue tape, then secure wire(s) to that with a conventional high-temp tie wrap. Same concept as the rubberized tie-wraps mentioned earlier, but longer-lived.

Those high-temp tie-wraps surprised me with their heat tolerance. I used a few to bundle EGT and CHT leads that came close to the exhaust primary tubes, and no melting or degradation in 440 hours.

In back of the engine, I had just one case of potential chafing that was unavoidable...a throttle cable against a scat tube...and the solution was to bond the two together so they move as a single unit.
 
Or is it acceptable to bundle them together

Generally, no.

A scrap seat belt anchor fit perfectly to make a bracket to secure that wire bundle.

That won't last.

3. Does anyone have any pictures of how they secured and routed their starter power wire? Im having trouble doing so in a way that doesn't put a tight bend in the wire.

Electrons don't care about tight bends, and it won't hurt ductile wire to form it.

Routing wires and hoses along the sump flange is good, but it can be a real beatch to compress an Adel and get it over the sump bolt, then get the nut on with limited overhead room.

Instead, cut a steel plate about 1-1/2" wide and long enough to drop over two or three sump bolts. Now you can Adel everything to the plate, then drop it over the sump bolts.
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OP31

Van's refers to the tabs as C-606 Link. Could be made yourself, but pretty cheap from Van's.
 

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I thought about this too, but the wires do not contact the metal braid. The hose itself is insulated with plastic, presumably to avoid chafing everything nearby.

I would not depend on that plastic in the engine compartment. Firesleeve maybe, but I expect plastic will age rather quickly. In any case, it is not accepted practice to run electrical and fluid/pneumatic lines together.
 
Yep. The insulation from the raw braid fixes the accute issue, but the chronic problem of electrical wires in contact with flamable liquid hoses remains.

When I first got the RV-8, the BATTERY CABLE WAS ZIP TIED TO THE 3003 ALUMINUM FUEL LINE IN THE COCKPIT!

10 years later, that still gives me the willies.
 
Van's refers to the tabs as C-606 Link. Could be made yourself, but pretty cheap from Van's.

Thanks! I've been staring at OP-31 all day and never saw that note! Selective blindness. I ended up making a couple of these links from 1/16" steel sheet I had lying around, and secured the wires to the sump bolts as recommended by others:





Unlike the seat belt anchor, these look like they will not flop around under vibration. Got the metal lock nuts on order from Spruce, so I'll replace the nylon stuff later on.

Also separated the hose from the wire runs, which looks like everyone's unanimous on:



I know every engine is different, but it would have been really nice if the plans called out guidance on where to run and how to secure the common major wires. I'll be working on the ignition wires, EGT/CHT wires, and magneto P-lead wires soon and will be back in the same boat.
 
...I know every engine is different, but it would have been really nice if the plans called out guidance on where to run and how to secure the common major wires. I'll be working on the ignition wires, EGT/CHT wires, and magneto P-lead wires soon and will be back in the same boat.
Check the RV-14 "360" pictures - that gave me a lot of hints on how to do it. Essentially, I followed these "rules":

  1. Remember the engine shakes like a wet dog - plan for a good transition from the moving part (engine) to the non-moving part
  2. Use all-metal locknuts everywhere - avoid the nylon lock nuts
  3. avoid zip ties if you can - and you can - I used lacing
  4. use adel clamps - lots of them - they look clean and hold things in place
  5. look for chafing possiblities and obviously avoid them
  6. route things as directly as possible
  7. use heat shield on the exhaust to protect anything that might get hot - don't forget your cowl

I could expand the list to about 20 more things, but I guess you get the idea.
 
Even though the braided hose has a PVC sleeve over the braid, an arc from an electrical wire can pierce the cover, the braid to the hose liner. IN your case its a MAP hose. Nevertheless separate hoses from anything electrical.
Tom
 
Looking for opinions on a few FWF items I've been working on lately:

1. Securing wires and hoses. I've opted to use adel clamps attached to the engine mount to make sure that my wires and manifold pressure hose stay put. Is it recommended to use one clamp for wires and a different clamp for hoses? Or is it acceptable to bundle them together:



2. Securing starter and alternator wiring. I routed both the alternator B lead wire and starter power wire forward along the right side of the engine. A scrap seat belt anchor fit perfectly to make a bracket to secure that wire bundle. I used what appear to be an unused 5/16-18 threaded hole just above the air intake. Question: Is this really unused and free for me to abuse in this way?



3. Does anyone have any pictures of how they secured and routed their starter power wire? Im having trouble doing so in a way that doesn't put a tight bend in the wire.

you may consider using two holes to support that long white electrical bracket.
 
you may consider using two holes to support that long white electrical bracket.

Decided to use small steel links that Vans recommends, running the wires along the sump area. Much more secure and stiff!

Also went ahead and replaced every nylon nut in the engine compartment with new all-metal lock nuts from Spruce. Feels good to do it right!
 
Also went ahead and replaced every nylon nut in the engine compartment with new all-metal lock nuts from Spruce. Feels good to do it right!

I've never understood this...the engine (assuming it's a Lycoming) *comes from Lycoming* with Nylocks all over it, so although it may seem like a great idea (AND there have been DARs who have insisted on it, despite Lycoming's seemingly apparent expertise in building engines), I just can't see a good reason to do it. Couple that with the possibility of a MIF, and that puts me in the camp of "if it ain't broke, don't fix it".

But, to each his own...
 
Mattituck - no nylocs

I've never understood this...the engine (assuming it's a Lycoming) *comes from Lycoming* with Nylocks all over it, so although it may seem like a great idea (AND there have been DARs who have insisted on it, despite Lycoming's seemingly apparent expertise in building engines), I just can't see a good reason to do it. Couple that with the possibility of a MIF, and that puts me in the camp of "if it ain't broke, don't fix it".

But, to each his own...
I have a Mattituck IO-360 and i can't recall seeing a nyloc. I just put all metal fasteners FWF to avoid any discussion. Perhaps overkill, but makes me feel good.
 
I find lots or airplanes with too many clamps where things can't move, everything is so rigid that it can't flex, this is far worse than too few supports so don't get carried away to make it look 'professional'. This is an RV not a space shuttle.
 
I have a Mattituck IO-360 and i can't recall seeing a nyloc. I just put all metal fasteners FWF to avoid any discussion. Perhaps overkill, but makes me feel good.

Yes, but I said Lycoming. Look, it's not that all-metal fasteners or bad, that's not my point. I was just saying that a FACTORY that has built these things for over 90 years ships them with Nylocks, so nylocks must be acceptable, right? IOW, there should be no discussion in the first place, unless someone wants to have it with the engineers at Lycoming.

It may make ya feel good, it's probably overkill, but IMO it's unnecessary (and does create a non-zero risk that something gets messed up during the replacement of all those nuts). New builders should take note, and proceed with caution if they choose to follow suit and make changes like this.
 
As mentioned - use lacing tape instead of zip ties. Lighter, cheaper, stronger, higher temperature capability and easier to install in tight spaces.

I used the black with latex coating and it is not sticky.
 
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