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How does my starter cable routing look?

Michael Burbidge

Well Known Member
I'm just beginning work routing and securing wires forward of the firewall. One of the first wires I secured was the starter cable from the starter contactor to the starter. I wanted to get some feedback on whether the way I've secured and routed it is appropriate. Here are some pictures.

Beginning with the contactor which is in the standard position.

sZM5mwd.jpg


I route it straight from the contactor to the engine mount on the lower opposite side of the engine.

JdyddHy.jpg


From there the wire takes a gentle half loop and is attached further up to the next engine mount support bar.

KkGK7nf.jpg


Then it goes inside the intake manifold pipes and the exhaust pipes up to the middle-side sump bolt.

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Finally it goes from the middle sump bolt to the starter.

hEeRGsz.jpg


Each of these hops is about 10 inches long. The last hop is more like 8. The cables are the welding-type cables from B&C.

What do yo think?

Thanks,
Michael-
 
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Very clean and professional installation. Looks almost like a certificated airplane.

Someone is likely to say to put a "boot" over the connections to prevent shorts in case something falls on it. I have no problem with it as it is as this is an intermittent circuit that does not continuously have power applied to it.

IF you want an award winning airplane, the boots will get you extra points.

EAA TC
FAA A&P
FAA DAR
 
Thanks for the guide

Michael for what it's worth I going to use your photo's as a guide when I wire mine. Looks great! :)
 
Very clean and professional installation. Looks almost like a certificated airplane.

Someone is likely to say to put a "boot" over the connections to prevent shorts in case something falls on it. I have no problem with it as it is as this is an intermittent circuit that does not continuously have power applied to it.

IF you want an award winning airplane, the boots will get you extra points.

EAA TC
FAA A&P
FAA DAR

A "standard" boot at the starter end is going to look tacky because of the 90 degree terminal at that end...

ELECTRICLnIPPLES.jpg
 
I installed a flat ss standoff at sump bolts then installed #2 ga starter cable on bottom and alternator 6 ga on top.

Soldering all of your fat cable terminals will provide better connections.

Mark and remove oil drain back tube clamps to trim off excess then smooth edges. Saves weight and makes working around those areas easier/safer down the road. Retighten these after 10 flight hours.

Keep truckin, not much longer.
 
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In your last picture, I see you have a 90deg crimp connector. My plane 'ate' (broke) two of these early on (vibration) before I changed the cable to a 'straight' crimp connector with a big loop coming in from the side. Either way, a boot is a good idea :D Rosie
 
90 degree vs. straight terminal

Rosie has a valid point. The roll vibration will quickly fatigue the ring at the starter in bending. I'd better take another look at mine... - Roger
 
I always want to see a service loop at both ends to allow for inevitable changes. For example, if you decided to go with a different starter down the line (lets say your starter quits in the middle of nowhere, and your only choice is to use a different one), with a service loop you have some flexibility there (pun intended.) Same goes at the contactor end. Generally there should be an adel clamp to support the loop so that vibration in the wire does not cause a premature failure of either the terminal or the bolt.
 
Your motor mount is in a fixed position and each of the bars are in the way of something. My point is, to reduce clutter and make it easier to maintain, run all cables hoses wires and anything else that you can, along the motor mount tubing instead of across them.

I found it much cleaner to run the starter and alt. cables down the right side of the motor. The battery, solenoids and alternator are all on that side. From the starter solenoid, I dropped down to a mount tube and followed it to the pan bolts then followed the pan to the alt. then to the starter.

This theory really applies on the top of the mount where you are reaching in to replace the filter or work on the mags, fuel pump, oil lines, fuel lines etc,etc.
 
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In your last picture, I see you have a 90deg crimp connector. My plane 'ate' (broke) two of these early on (vibration) before I changed the cable to a 'straight' crimp connector with a big loop coming in from the side. Either way, a boot is a good idea :D Rosie

I'm not a big fan of Amp's single thickness terminals for large [8 AWG and larger] cables. Lots of vibration from the engine causes fatigue failures. See my comments and suggestions in the threads linked below.


http://www.vansairforce.com/community/showthread.php?t=43785&highlight=Burndy+terminals

http://www.vansairforce.com/community/showthread.php?t=9189&highlight=Burndy+terminals

You might want to consider switching to the sturdier Burndy terminals if you have problems with the Amp terminals in the future.

Charlie
 
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I always like to see ample slack where cable cross from firewall to engine. the Lycoming wet dog shake can pull a taught cable loose.
 
I agree with rocketBob on this one. wire strain relief is one very important part of any electrical system. It will fail if not provided. It can be provided by a loop or a "s" in the wire. Just a reminder from an electrician. Be safe and enjoy.

Bird
 
hEeRGsz.jpg


Hi All,
Does anyone know where to source these 90 degree ring terminals (preferably some burly ones that won't fatigue fail). I can't find them on McMaster Carr, Steinair or B&C.
I've painted myself into a corner, so I've got some access constraints that mean that I can't get away with a regular crimp terminal.
Cheers,
Tom.
 
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