Antenna Help Needed
 

The power antenna on my '79 quit working. Apparently the cable inside that attaches to the mast to extend and retract it broke because it still runs by doesn't move. I'm trying to take it out to see if I can fix it but can't manually retract the mast far enough to get it out of the fender. I can get it to within 5" or 6" of the bottom and then it hits a hard stop. I need to get it to about 2" or less. I'd like to see if I can fix it so I'd really rather not bend or break it.

Anyone have any experience or ideas?

Thanks,
Rich

I've tried to replace the plastic retraction "cable" before and believe me, it's cheaper to just buy a new antenna. If you could find the retractor, it will probably cost just as much as a new aftermarket antenna. I never could get the retractor installed corrctly.

The original antenna in my 84 had the same problem (where the internal plastic/nylon push/pull cable snaps). The antenna motor still ran and would fully extend the antenna but would only partially retract the antenna.

Since my antenna was controlled by a switch on the dash, I had a helper inside the car flip the antenna switch while I stood outside the car near the antenna. When I heard the antenna motor run, I carefully pushed down on the antenna with my hand (didn't want to bend the antenna) and was able to make it fully retract. (Had to cycle it a couple of times so the motor/spool was turning in the retraction direction when I pushed down.)

Thanks for the input Haywire7. I've tried this, but I did it by connecting a power supply to the connecter in the rear area so I didn't need to use the switch. Maybe I'll go out and try some more...could be that things have to be lined up just right to make it work.

Rich

Rich,
Common problem unfortunetly. The plastic rod that extends and retracts the antenna mast gets brittle and breaks. I make it a point not to use the antenna when it gets colder. Anyways, sounds like it won't go down all the way cause its at the point where the break is at the spool and you are unable to force the rod around it. Like trying to force a broken tape measure to coil back up inside.

You may be able to un mount the motor and turn it in the fender so that you can remove the round cover and spool. I'd take both the inner fender and rear tail light out for access. Once thats off, you should be able to push the mast down all the way and remove the unit w/o damage to the mast. Otherwise, you may have to cut the antenna mast for removal.

Of course the replacement masts are long gone, but if you look on ebay, you'll find replacement units for about $70. Mast, motor and everything. There was a thread about these here a couple months back.

I think this was the thread:

https://www.rx7club.com/1st-generation-specific-1979-1985-18/possible-successor-radio-shack-power-antenna-962443/

OK, one last thought. Instead of removing the spool, I bet the clamp at the base of the mast could be loosened to seperate the mast from the motor while still in the rear quarter.

Photo courtesy of the Stu Aull collection......

Thanks for all the input banzai. I actually have an aftermarket power antenna that used to be in my '85. I didn't like it because it doesn't look at all like the original and I'm trying to keep my '79 as original as possible. The mast is thicker and not as shiny. If I am unable to fix the original, I'd at least like to get it fully retracted and leave it in place and install one of these:

http://www.ebay.com/itm/Shave-Hidden...#ht_1182wt_906

When I had the bodywork done on the '85 I had them plug the antenna hole and installed one of these on the inside of the windshield behind the mirror (see attachments...it's the long rectangular one on the right...the other is for my alarm). It actually works quite well. I think the FM reception is just slightly worse than an external mast, while AM reception is just slightly better.

How does the mounting bracket of the stock antenna attach to the bottom of the "winder" assembly? If I could get the bracket off it might free up enough room for me to wiggle it down into the fender and out the taillight hole.

Thanks,
Rich

Two clamps, a stablizer strap at the top with a 10 mm hex nut and one at the base with a small phillips head strip-o-matic screw. The trick will be finding a 5 year old with small enough arms to work in there. That antenna you have is pretty slick. I don't know of a good way of fixing the OEM ones. Wish I did.

I'd like to see your early build 79 sometime. We'll have to arrange some time next year. I'm up to J&P in Anamosa a few times a year normally. I'll have to take a car sometime.

Yea, I had this antenna out many years ago and I was thinking it was a phillips screw...gonna be difficult or impossible to remove. If I was sure it would allow me to get the antenna out without retracting the mast fully I'd take a dremel to the bracket and cut it off. But I really doubt that it would help enough.

Yea, we'll have to get together sometime after mother nature allows us out again.

Thanks for all your input.

Rich

I finally had some success with this. I decided to separate the mast housing from the motor/winder assembly by removing the 2 small screws at the base of the mast housing. Since the nylon cord inside was broken, this allowed me to completely separate the mast from the motor/winder and extract them from the fender.

Call me crazy, but I think I can fix this bad boy! The button on top of the mast is threaded on. Once I removed that I pulled the top mast section out from the bottom, which still had the remainder of the nylon cord attached to it. I cut that flush where it's crimped to the mast section, then used successively larger drill bits to drill out the remaining chunk of nylon cord. The final little bit I was able to scrape out with a real small screwdriver, Exacto, and tweezers. So now I just need to insert the remaining nylon cord (it appears there is plenty still remaining, but I might buy some new) and crimp it tight. I'll probably help it along with some sort of epoxy. Then it's just a simple matter of reassembly!. I'll probably take this opportunity to clean everything up and paint the housing...don't want people seeing that crappy looking thing when they look inside my fender!

Rich

I'd be afraid the original nylon cord would just break again, but if the remaining length still seems flexable it may be worth a chance. Years ago, I looked at fixing a mast that broke this same way. I never thought to unscrew the knob and get to the actual crimp point. I had the nub hanging out the end of the mast and couldn't find a good way to splice it back or attach some sort of replacement cord. Your solution solves that by just recrimping! The simplest solutions are the best.

I always thought a good replacement might be a length of bicycle cable sheathing. Not the wire rope cable but the outer protective sheath. It's normally wound like a coil bound spring and covered with plastic. I believe it would coil up on the spool and be less apt to fail over time like the nylon. I still have that old mast and will have to give it another look.

Please Rich - if you DO figure something out, document and post it OK!?
Mine is starting to act up too ;(

Thanks for the pix. Neat to see the inner workings.
cheers
Stu Aull
80GS
Alaska

The flat metal spring is a pain in the ass to get wound back up again and stay in place. I tried redoing my antenna years ago and gave up.

Yea, that's why I am probably going to replace it...don't want to do this again. It looks like it's just 1/8" nylon like you'd find in a huge weedeater, so I'll look for some of that. I figure if it lasts another 33+ years that'll be good. I'll be 90 by then LOL,


I plan on documenting my work, although it looks like it might be at least a few days. Winter has finally set in, and since I'm retired and don't HAVE to go out, I won't LOL


Flat metal spring? Hmmm...don't recall anything like that. I'll have to go out and take a look.

Rich

I just replaced this part on my 85. You can a new antenna/cable assembly (minus the motor to save a little money) at a Mazda dealership. Mazda still makes that part, but its not super cheap. It will cost more than a cruddy new universal antenna. The factory service manual (which you can find as a pdf with a google search) tells you how to install it. Not too tough.

Looking at it again, this one looks different then the one I had. Mine had a flat metal spring, similar to a lawnmore pull rope, that retracted the mast.

Antenna help
 

Can you tell us the part number for the antenna /cable assembly? My local dealer has no reference for older RX-7s. Do you know if this part works with 79-80 vintage cars as well as the 85?

Never thought of this. I just looked it up and it looks like it's Key No. 66941, part number 8341-66-941 and they call it "Pole, Antenna". I'll have to give the dealer a call and check on it. But I think it's just the mast, and not the nylon cord and winder assembly. Don't know for sure.

Rich

I'll try and check for the part number tomorrow. I think the package it came in is over at my father in law's garage. The antenna pole did come with the nylon cord. There were only two part options that they gave me at the dealership: mast (with cord), or complete assembly with the motor. I would think that it always comes with the cord, because attaching a new nylon cord would be tough.

The 79 Factory Service Bulletin, pages 36-39, details the antenna repair procedure for Mazda dealerships. It shows all the antenna components, listing the replacement mast (they call it the pole subassembly) as P/N 8869 66 9410.

This is the SA one with the nylon cord and also lists out a crude assembly process. Total labor was .8hrs and it even reveals Mazda had a 1yr / 1200 mile warranty period on the original mast! They changed the antenna design in 81 with the FB cars and I have been told the masts don't innerchange. Can't speak about availability for an 85, but the replacement SA masts have been NLA from Mazda for quite a while.

Antenna help
 

I have a 1980 Workshop Manual (my car is an 80) but it does not cover the repair procedure to fix the antenna. Would you be able to forward (scan, email, etc) or post a copy on this site, of those pages referenced above? I and others would be appreciative. Thanks.

This is a service bulletin, not the service manual. I have an 80 as well. They cover all the Mazda models not just the Rx-7 and are meant to update the manuals with additional information and changes that occured and/or corrections to the manual. I may be able to scan in the few pages you are asking about, but it's pretty basic and somewhat simplified compared to the manuals. Nothing there that you can't see and figure out by disasembly.

This website has the 1980 manual as well as several others. It also has the 79-80 parts catalog, so you can try looking up a number.

http://wright-here.net/cars/rx7/manuals.html

The part I got is labeled: Pole, SU
Part # FA42-66-941A


This is for an 85, but it looks similar to yours and may be interchangeable. It has a smooth, round nylon cord attached to the antenna. If the length of the assembly is not exactly the same, it should not matter. The antenna is turned off at the end of extending or retracting by a voltage actuated switch when the voltage it draws increases due to it hitting its stop. The motor will run until the antenna assembly fully extends or retracts, regardless of its length.

Be sure to grease the assembly (try lithium grease) before you reassemble it. I didn't put any new grease in mine and it was a little sticky at first. I will probably end up taking it out and adding grease later just to extend its life.

OK, here are the pages out of the service bulletin, alerting dealerships of the replacement mast (sounds better than pole) and how to replace. As a bonus bit of SA Trivia, I also included a blurb which reveals that on January 27, 1979 and begining with S/N 540387, they made the change from the "always on" A/C fan switch, to having the seperate push button one. I know thats been keeping a lot of people up at nights, so I figured I'd put that one to bed....:gwink:

Possuman, the FB replacement mast has a larger diameter aluminium tube then the SA one and won't fit in the base of the housing. Part of the design changes to the antenna assembly in 81.

Banzai Thank You for posting the information it's very helpful. Now I can tear out the antenna assembly and have at it.

I'm surprised to learn that 1/8" nylon line is hard to find. I've found trimmer line that is .105 and .155 but not .125. So I started looking for other nylon/plastic line and searched McMaster-Carr and found some 1/8" nylon rod. I sent them an e-mail to ask if it would be flexible enough to coil into a 3" to 4" coil and they said no, it isn't. But they recommended some plastic welding rod. I have no experience with this stuff. Can anyone tell me if it would be a suitable replacement? Would it stand up to being coiled up and uncoiled hundreds of times?

Thanks,
Rich

Rich,
so the .155 could not be made to work? Will it not fit in the mast or housing body? If it's just too big to fit in either of the crimp ends, couldn't you thin down the ends with a belt sander/grinding wheel or file? I remember speaking with a guy who welded plastic. He had a booth at some event I was at and I'm always interested in things like that. His filler rods were hard (solid) , like what you'd use for TiG welding. Also, not long enough. What you want would be more like a MiG process, on a spool. Not sure they even have that. I'm confident there is a way to accomplish this, just have to find the right material. Have you looked for a local plastics distributor? There used to be one around here I bought Lexan from. They also had various round and structural shaped nylon, teflon and plastic.

Almost there
 

The antenna on my 80 LS wouldn’t go up or down however when I pressed the actuator switch I could hear the antenna actuator motor run and the ratchet in the drive clutch click.

So with the information provided by Banzai and 64mgh I decided to try and see if I could fix it. I removed the antenna and disassembled the unit and was surprised to see the drive cable was still in tact. After cleaning the unit and lubricating the mast segments I reassembled the unit. By turning the outer drive mechanism by hand I could get the antenna to go up and down which it didn’t do before cleaning. Before reinstalling the unit I decided to test it to make sure it worked properly. I plugged it in and pressed the up button and it worked. It extends to full length and then heard the clicks at the end of its travel and the hum of the motor. However when I press the down switch nothing happens, I don’t even hear the motor hum. So I’m thinking maybe a bad switch. Before I tear the center dash panel apart to get to the switch does anyone have any other thoughts on why the antenna will not retract?

The switch would be my first guess. Getting to it, is easier than getting to the antenna. I've had these (as well as others) go bad before and keep extra dash switches on hand, just in case. It's a simple to plug in another switch and try. I have also fixed bad switches by taking them apart to clean & bend the contacts. there are a few parts to them and they can fly apart if your not careful.

Surprised that it was just gummed up and the rod is ok. That's a plus. You didn't measure you rod did you? I'd like to know the length of one without disassembling a whole unit. I have a possibile replacement material but don't know how long to make it. I only have bits and pieces of an old broken mast rod.

I haven't put it back yet and it's still fully extended. From the top of the threaded segment for the nut of the fender mount of the pole assembly to the bottom of the button screwed to the upper most antenna segment is exactly 46 inches.

Finally fixed
 

Continuing on with this saga, I pulled out the FSM and found out you can simply pull the antenna actuator switch out of the console fascia which makes it extremely easy to get at the switch. I checked the switch continuity and found no current reading for the down side of the switch. Ok so now I know part of the problem. I removed the two screws on the back of the switch and then removed the cover. Inside the switch are two rocker contacts that will touch fixed contact points on the switch plate back when depressed. They also fall right out of the mounting tabs when the cover is removed so if you disassemble the switch be careful not to loose them. Upon inspection I found a lot of “dirt” on three of the four contacts, other than that it looked to be OK. After cleaning the contacts I began to reassemble the switch. I dropped one of the rocker contacts and then one of the screws which of course fell through the switch opening. After removing the shift boot and 35 minutes of fiddling to retrieve the parts I finally got everything back together. It took longer to retrieve the parts than actually remove, clean and reinstall the switch. After reassembling the switch I checked the continuity and now had reading on both the up and down side of the switch. I plugged in the antenna assembly and cycled the switch. Everything worked!

So in summary I would suggest checking the switch continuity as well when you are experiencing problems with the antenna operation. In my case it may have been only a bad switch and not the antenna assembly itself. I hope this may help someone down the road.

Yea, just removing the shift knob and two screws gains you access to unplug and remove the switch completely in about 2 minutes. That's why I said it was easier to gain access to the switch than the actual antenna. The simplest thing is just to plug in and try another switch. From there you can decide to take the old one apart on the bench where your less apt to lose small parts. Work smarter not harder.

Normally, the antenna fails only when the rod gets brittle and breaks. You still hear the motor turning but have no more movement in the mast. When it does not move AND you hear no motor, it an electrical issue, most commonly found in the switch itself.

I still have an old mast that the cord kinked and broke years ago. Using 64Mgb's suggestion, I found some .130 dia trimmer cord to try as a replacement for the stock nylon suff. It turned out to be ribbed instead of plain round but looked to be the right combination of stiffness and flexability to work. I began with a 5ft piece which should be plenty long. It was actually about .160 across the ribs but this allowed me to trim down a half inch on one end to .130 for a snug fit where it crimped in the antenna's core rod. The pictures show the original cord, antenna parts and trimmer line.

After slipping on the rubber gasket, I inserted the line into antenna core securing it by restaking it with an automatic centerpunch. Next, you just slip the core rod back into the antenna and screw the knob tip back on. I don't currently have a broken antenna to test the final repair on, but it's well secured and I'm confident the trimmer line will work to push the mast up. You can possibilly find another material or additional means to secure it with, but this at least illustraites that it's possibile to fix these instead of buying a whole aftermarket antenna motor and mast.

Have you been able to actually run it on the car yet to see how it operates?
Also were did you get that trimmer cord?

Sorry...I missed these posts about the switch. Banzai is absolutely correct. I have fixed the switch in my '79 many times...so many times that each fix only lasts a few months now. The contacts eventually get smaller from arching, and the metal holding the contacts gets soft and no longer holds it's shape. I did buy a spare but it also failed after awhile. My plan is to install a 'hidden' replacement switch while leaving the original in the center panel to maintain the original look.

Rich

No, I don't currently have one that is broke. I do believe this will work. Here is a link to the line I bought:

http://lawn-and-garden.hardwarestore...0--616318.aspx

At $10, you get enough for several mast's. If you have one that is broke, PM me and I could fix one up and send it for you to install and try.

Yes mine is broken and I am interested in trying your solution.
I just have one question once the antenna is apart how do you get the new coil to catch on the reel?

http://www.mazdatrix.com/faq/86-92ant.htm

If you look at the 8th picture down, what is stopping the new coil from just coming loose?

A small section of the round container is cut out and folded in to crimp the end. You can sort of see it in the attached pictures.

Rich

Sorry...I didn't look at the MazdaTrix link before replying. That's a different antenna than the SA has.

Rich

No, that's exactly what I wanted to know.
I just used the mazdatrix link to help in my description to make things a little more clear because I didn't know how to describe it. lol

So I went to remove my antenna ad there is a random rubber hose attached to it. It was about 6 inches long or so but at the end it had a clean angle cut. What is it? and did I detach it to something or is it supposed to be like that?

It's a drain to drain water out of the mast.

Rich

I finally got around to working on this again. It looks great and works perfectly, except I hear a fair amount of gear noise when it's retracting. Going up it's nice and smooth and quiet. I don't remember it doing that before...is it normal?

Rich

I remember when mine moved up and down, when it was extending all you could hear was the motor turning to put the antenna up, but when it was going down it was much louder and noisier for some reason. I could never figure it out.

Its normal to have the louder clatter when reaching full extension or retraction, but excessive motor or gear noise in either direction of travel is not.

OK...Now that I'm ready to slide this bad boy back in, I need to know where the drain hose is routed. Mine had been cut off many years ago and I don't see or feel a hole for a small tube to go through. Anybody know?

Thanks,
Rich

When I was messing with mine, it was just routed down downwards in some aimless direction.
I didn't see anything for the hose to connect to either or even an opening for the water to escape.

I think he may be right. The aim was to drain the antenna mast, to Hell with your rear quarter!
Did you find a cause for the whine?