A little over a year ago I bought a 1985 GS 12A for my son. We had a lot of events slow our progress but we are back on task.

Here it is just before liberation:




Here is the car just after being liberated from its resting place:


Son's face obscured per his request.


And photos of the VIQ just after towing it home (from northern UT to southeast AZ) and bit of cleaning:




I'll add some posts for each step so far then add the photos after upload.

 

The only gages that worked were the tach, temp and oil pressure.

The instrument cluster was removed (getting the steering wheel off was difficult). All of the contact points were cleaned, all solder points were re-soldered.

After install the tach, oil, volts, and temp all worked but not the fuel level.

 

With the basic instruments working next came the carb. It wasn't bad but a good cleaning helped. It was removed, serviced, then reinstalled. After that the engine would start but not idle below 1300 rpm. We drove it a bit in this condition to shake out next steps.

And what did we find? You guessed it; steering relay.

 

For steering relay here is what I did:

https://www.rx7club.com/1st-generati...-slop-1142866/ (see my posts later in the thread).

"Well...

So far it has been 4 days and plenty of driving. By all accounts the bushings I made should have melted or failed. So far no issues.

For the technically curious here is what I did:
1) Bore the taper out of the pivot
2) Machine bushings from Tecamid PA66
- Bushings occupy all but about 0.080" of the length (a little room for compression) more than doubling the bearing surface
- Used EP nickel bearing grease (compatible with the PA66) on the bores and idler shaft
- Added seals
3) Install and torque to factory spec (after assembly torque to move the arms was just over 5 lbs by the way)
4) Drive.

At the melting point of the Tecamid the paint on the car should be bubbling so I think it will be fine."

 

The idle problem didn't get any better. Several times the engine stalled due to the fuel filter being plugged. Also from the cut-off valve getting stuck.

Eventually the tank was dropped and cleaned. While in there the fuel level sender was removed and all corrosion cleaned off. All solder points were re-soldered. Still no improvement (no working fuel level gage). Finally after reviewing the wiring diagram it was clear that something in the sender was wrong. A switch of two terminals rectified the problem. Now the fuel gage worked.

With the tank clean and the suspect cut-off valve replaced the fuel would flow reliably to the front. The carb however did accumulate some sediment due to the fine rust that passed through the filters.

 

Now to solve the idle problem. The engine starts quickly. Compression is not an issue. The carb was removed again to clean it. During disassembly it was discovered that the secondaries were stuck. Also that the shutter valve in the intake manifold was stuck. OK then...

The carb was treated to a luxurious ultrasonic bath. Not only did this remove all the sediment but also freed the secondary shaft. The pieces were pulled out of the bath while hot to help them dry. A little compressed air made sure all was clear and dry.

During reassembly there were a few minor changes made.

1) Accelerator pump diaphragm from a Yamaha XZ550R. It fit the carb but the housing needed a little boring because the shaft on the diaphragm is larger OD than the OEM. The prior part from the recent rebuild had failed so I found something better.

2) Also the great secret (probably already known) to removing the accelerator pump in-situ depends on what you do when reassembling the carb. Put the top two screws and the bottom right screw (the one obscured by the pump lever) in and tighten them. Leave the bottom left screw out. Reverse the pin and insert it into the pump lever and housing. Put the e-clip put on the other end, now to the right side, to hold it. Now put in the last screw. Now if this new diaphragm fails I can perform the reverse steps to remove/replace the diaphragm without disassembly of any other part of the carb.

3) A small (4mm) reamer was used to open the accelerator pump check valve passages for a slightly larger ball. One was missing from the carb and I didn't want to buy a whole kit or carb to get one 3mm ball. The passage was reamed to 4mm and the missing ball replaced with a standard 1/8" bearing ball.

 

Perfunctory reference photos of the carb. An untouched, one-owner vehicle with everything in the correct (OEM) place.

I took these photos because the vacuum diagram stuck to the hood is so easy to read.



Reference photo of carb and lines.



A note on sealing washers. Some kits are furnished with washers made from gasket material. If you don't want to use them and have been able to disassemble the fuel manifold without damaging the aluminum washers they can be reused.

To use a copper or aluminum washer again they need only be annealed. I use a small butane torch to heat the washer while holding it with needle-nose pliers. Heat the washer until it changes color. With aluminum don't overheat and melt the washer. Keep in mind the washers will be thinner from prior crushing but in cases with generous tolerance softening the washer by annealing will allow at least one reuse.

 

Great job so far! My dad did the same thing with me 17 years ago. I'm now on my 4th and forever car, a 85 GSL-SE.

He wont forget any of it

 

Last week my son took the car to school. He is in auto-tech this year. He and a friend serviced the front calipers (seals and dust seals). The hoses are in remarkable shape so we are guessing they were replaced a few years back. All brake hoses are on the replacement list. I think suspension bushings will be next.

 

Since the last report the car has been driven almost daily. It continues to start easily and run well. Not bad for a rotary with 127k+ miles of service so far. There have been some small repairs (soldered a hole in the top radiator tank where that silly bracket for the fan cowl connects) but the car just runs and runs. Since we started this project my son has done the maintenance items in his auto tech class. He is now in auto-tech at a local college and looking forward to more work on his car. One of his classmates has an '85 MR2 so they are talking 80's cars. My son was complaining about having the lowest HP car in his class. I told him that while impressive HP is fun that a Charger Hellcat is a broadsword and the RX-7 is a dagger. It depends on your style. :-)

Regardless of that we are now considering a 13B swap for two reasons. The first is more power. The second is to preserve the long-lived 12A for a long-term rebuild/restore.

The current plans are to move on to paint/body next month when the weather cools a bit. Right now we are removing and preserving the Clarion audio system to install a new JVC (he wants bluetooth for his phone and such). It gives us an opportunity to check out the wiring, connectors, ground points, etc.

 

Sounds like you snd your son have done a great job on the car!! The 12A is near bulletproof of its maintained properly. The 13B swap can be done but it does require quite a bit so prepare for that. I swapped a GSL-SE engine into my 85 GS and it was an incredible experience. I did the swap in 2008 and I still drive the car today. Rock solid reliable. But I rebuilt everything on the car as you would expect.

How's the interior holding up? Is yours maroon or gray? I love the color of your car. Sparkling Black Metallic is one if my favorite colors on the 85!