1965 C337 "Alternator not charging" light - Page 2

DrDave · #16 02-22-19, 12:20 AM

Hi:

There is going to be an avionics master switch on the panel. It will go from a breaker on the main bus to the switch and then back to power the shorter avionics bus on the lower row of the panel. There are two separate buses on the bottom row. There is an empty breaker next to the avionics bus that will feed the avionics master switch and bus. BTW, that narrow jumper will carry 105 amps.

I do not recall the size of the lugs on the starter. I will look tomorrow and let you know. Do you have the crimp tool for the larger size lugs? As I recall that was a $350 investment in that crimper.

Dave

cessnadriver · #17 02-22-19, 09:15 AM

Dr. Dave. I found that Harbour Freight has a hydraulic crimper 14-0 AWG. The price is $55. Will you install a relay between the main to avionics bus? I installed one on my Cessna 172 to avoid pushing high amps through a switch?
Thanks for the reply.
Regards, BILLS

DrDave · #18 02-22-19, 05:21 PM

I'm skeptical of the quality of that crimper. If you save the $55 and measure and mark your wire you could send it to me and I'll crimp it for you. I'll even label it and shrink tube the terminals. I have the terminals too. I'm guessing it will be around 15' of wire.

I have no plans to put a relay in the circuit. There is no large load on the circuit. The only load even worth mentioning is during transmit. It's <5 amps. I will be using a Cuttler-Hammer switch. I can't remember the part number right now. I'll look it up.

Dave

cessnadriver · #19 02-22-19, 09:00 PM

Dr. Dave.
Thanks for the heads-up on the crimper. BUT I already bought one to try. Thank you for the offer to crimp my wires-though. I have another option there is a company there that I use to work for that does a LOT of wire crimping, aviation standard stuff. I could have them crimp them if needed!
Regards, BILLS

DrDave · #20 02-23-19, 12:12 AM

That sounds like a very good option. When you fit your wires mark a line on the wire for alignment of the terminal. This is important on the larger wires. Send pictures.

I just added a few pictures for you. This is the type of crimper you want to use. I also included a crimped connector to show what the finished crimp should look like.

Dave

cessnadriver · #21 03-07-19, 09:25 AM

Dr. Dave. Would you be willing to give me your e-mail address? I have a few questions and it would be great to e-mail you directly? IF not one of the questions is. You want me to replace the 12 gauge (the original gauge) wire to a 8 gauge? From the alternators to the shunts and from the shunts to the circuit breakers? If so this would be a modification to the original wiring REQUIRING a Form 337 "Major Alteration/Repair" approval? PLEASE ADVISE! My email address is bstory@pa.rr.com.
Many thanks, BILLS

JAG · #22 04-01-19, 11:14 AM

Hi Dr. Dave,
Well, I have also taken your advice from this thread, and I have started to run the new wires from the starter (GND) to starter, and new feed wires. As I am going through a major refit on the aircraft including avionics, I thought I would have another look at the back of the CB panel to see where I would install some new CBs...well, I did not sleep well last night thinking about the 1966 panel that has been added to over the years. I have resigned myself to the fact I just need to clean it all up. This will be a big job - and I am hoping to get any guidance/templates/words of wisdom from you on making this a modern install. I have looked at your pictures and like what I see. Do you have some info you could share on the layout, copper bus bars, etc that you did in designing yours. I was hoping to keep the same Front Panel, but I may have to fabricate a new one to accommodate the new CBs and also have the front properly marked. I still have your phone # from when you helped me out with the rudder bar bearing block...let me know if you want my personal email.
Jeff

DrDave · #23 04-01-19, 03:14 PM

Hi:

I'm running off an avionics master breaker to a switch and then back to feed the entire avionics bus. You could run to two switches for a backup avionics switch if you want. As I recall the starter mounting stud was larger than 5/16". I will measure tonight and report back.

Dave

JAG · #24 04-02-19, 09:30 AM

Dr.Dave,
Thanks for the tip on the Master Avionics Breaker and Switch...Had not thought about that. With building a new CB panel, I like the ability to isolate certain things.

Yes, the studs on the starter are 3/8". I went ahead also and bought a large stock of terminals, wire and a good crimper that goes up to 4 AWG. Even though I have 30 amp alternators on my bird, I am going to upgrade the wiring from the alternators and the shunts. Since I have the aircraft completely opened up and changing throttle/prop cables on the rear engine, it is so easy to run new wires.

Jeff

DrDave · #25 04-04-19, 11:21 PM

Yes, just measured it at 3/8". I'd love to see a pic or your new circuit breaker panel. The shop that cut mine for me has the template in their computer. It would be no big deal to have another panel cut. I have some extra spacers if you need to shim out the panel a bit.

Dave

DrDave · #26 04-04-19, 11:44 PM

Jeff:

Somehow I missed your previous post. I'd be glad to help and share what I have learned. I had the same goal as you in keeping the original front faceplate. I think it's nice to ditch the thin piece of aluminum behind the faceplate. There was a bit of corrosion between that plate and the breakers. The first step is probably the sub-panel that the breakers mount to. The only thing that makes that a pain is the little locator holes for the breakers. As I mentioned in another post the shop that did mine has the whole thing laid out in their program. I'm sure we could have them cut one out. At this point we should probably have a few of them made. After the mounting panel is done it's a matter of ordering your new breakers. I'm very pleased with the 2TC2-x Klixon breakers. The 35 amp breakers are 3TC2-35.

The busbars are going to be straight forward for the three straight pieces. The jumpers will have to be hand formed. Call Charlene @ Quick Ship Metals at 888-334-2177 and order your copper materials. If you get a 6" x 12" piece you'll have plenty. Have Charlene cut your individual bars for you. She has a better shear in her shop than I have. I will have to measure my pieces again to give you the exact measurements. They will still have a bit of a twist from the shear but they straighten right out. Have her cut six individual pieces. Undoubtedly there will be some where your holes don't line up. You will be hand-drilling for each breaker.

What color do you want your sub-panel piece?

While you're at it make paper templates of the circuit panel enclosure. Take those templates to your local plastic place and have thin polycarbonate pieces cut to form an insulated circuit panel enclosure. If you don't have a favorite plastic place just mail them to me. I think mine cost $8.

This will be a fun project, don't be scared.

There are a few other tips that will help along the way. I will get you the part number for the avionics switch I like.

Report back.

Dave

JAG · #27 05-13-19, 09:47 AM

Dr. Dave,
My apologies for the delayed reply, but thank you so much for the info and direction. I ordered the CB's and copper (from Quick Ship Metals) you referred to, and assembled my CB panel over the weekend. It took some time to get the layout right, as I not only wanted to use the original face plate, but wanted to have the circuits laid out in a logical fashion. I have an expanded avionics ("electronics" in Cessna Language) bus given the new avionics I am installing in the aircraft. I have had a custom vinyl overlay being printed in the original Cessna font, and so the panel will look very original.

I am now in the process of wiring up the new CB Panel, and it is taking a little bit of time since all the terminal ends need to be upsized for the #8 screws. My 1966 model has 30A alternators, but I have replaced the wiring from the alternators with 10 AWG (original was 12 AWG) and all new wiring and terminal ends for the entire GEN control system. I have replaced and moved the shunts for the two alternators, installing Hall effect sensors with a new gauge from Aerospace Logic , VA202K. They were able to reprogram the gauge to read "Front" and "Rear" from the typical "Left" and "right" in most twin gauges.

What seemed like a herculean task, is not too bad once you dive into it. Thanks for the encouragement. Not only has this allowed me to go through and inspect every aspect of the electrical system, but I now know it so well. I even dream (more like night terrors) of electrical schematics and wire numbers. I have put my Dymo label maker through its paces creating new heat shrink wire labels for all the new wire runs.

Thanks again,
Jeff

DrDave · #28 05-13-19, 03:16 PM

Jeff:

In looking closely at the new panel it appears that you have the taller 3TC breakers. Is there enough clearance on the back side for those? I love the picture of your old circuit panel, otherwise known as what could possibly go wrong here. Your new panel looks good. Are you doing a dedicated avionics bus? It is interesting to see the burned terminal connection in the bottom left of your old circuit panel. That was causing problems somewhere.

You are doing a really nice job on this project. This will be a great system once installed.

Dave

JAG · #29 05-13-19, 03:39 PM

Dave,
Yes, it is a tight clearance. Without the sidewall in place, there is clearance, but it is close. I just double checked my part numbers, and it looks like I did order the tall ones...dammit. I ordered the 3TC7, not 3TC2!!!! Looks like I will be ordering those 3TC2 breakers today!!!! That should give me an extra 0.5".

Thanks for questioning me on that. When I fit it over the weekend, I was not happy with the clearance, but felt once the sidewall panel was it, it would give me some more...but if I can put in lower profile CB's, that is much better in the long run.

Yes, I am doing a dedicated Avionics Bus - the lower row (RH side of picture) will be the avionics bus, controlled by a Avionics master in the panel.

After seeing your pictures of the old CB panel, I looked at mine and could not believe how bad it was. Some smoke was definitely let out of that one wire on mine - not to mention the crappy aluminum bus bar...barely rated for the Skymaster system.
Jeff

DrDave · #30 05-13-19, 03:46 PM

Jeff:

You may want to consider a spacer between the panel and the mounting holes. This would look like a license plate frame. I'll send you pictures. I would also encourage you to line the panel area with thin pieces of polycarbonate. The biggest offenders in your picture is the tie bars. The tie bar you have pictured should be good for 400 amps. I made the same mistake with the 3TC-7's the first time as well.

Dave