64mgb

iTrader: (1)

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

KansasCityREPU

iTrader: (9)

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.

Haywire7

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.)

64mgb

iTrader: (1)

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

Banzai

iTrader: (13)

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.

Banzai

iTrader: (13)

I think this was the thread:

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

Banzai

iTrader: (13)

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......

64mgb

iTrader: (1)

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

Banzai

iTrader: (13)

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.

64mgb

iTrader: (1)

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

64mgb

iTrader: (1)

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

Banzai

iTrader: (13)

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 **** 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.

7aull

iTrader: (2)

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

KansasCityREPU

iTrader: (9)

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

64mgb

iTrader: (1)

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

possuman

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.

KansasCityREPU

iTrader: (9)

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.

80RX7LS

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?

64mgb

iTrader: (1)

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

possuman

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.

Banzai

iTrader: (13)

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.

80RX7LS

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.

Banzai

iTrader: (13)

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.

possuman

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

possuman

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.