Hi,

I introduced myself back in December last year, we have bought what is probably, out of a handful of RX7s in Kenya, the only one left with its original engine. They love converting them to 4 cylinder power over here! The car is a 1982 FB RHD ex UK
The car was parked quite a few years ago with starting problems, apparently towing it was the only way to start it.
Yesterday we took the engine out, and it turns out there was coolant in rotor 1, so it will need a rebuild.
The air pump is seized, and the small pipe to the thermal reactor is damaged. Can I just remove the air pump and block that small pipe?
Obviously here emissions are not an issue...
What else would I need to remove or block? I am quite keen to simplify as much as possible!

J-P

 

welcome to the board.

yes, you can remove the air pump (and a few other items) and block everything off.

https://www.rx7club.com/1st-generati...emoval-797455/

 

Thank you for that advice!
I have searched on the net for an engine rebuilder and a spare parts supplier (so far mainly brake parts), not much luck so far.
Can anybody recommend either?
Your advice will be much appreciated, I need to move this project forward!

 

Congratulations on your new purchase. Another rotary waiting to roar back to life on our motherland Kenya.

Pretty hard to find 12A parts from all over the world. My best bet would be a 13b N/A swap as there are quite common in south Africa.

We have quite a number of FB rx7s still on their original 12A motors in Nairobi mine being one of them running fine but also low on compression.

We have an RX7/8 group with around 8 1st generations still on our roads today.

Feel free to get in touch.

 

Thanks Douglas, very interesting! Would you please call me on 0706173105?

J-P

 

I am a total beginner with no auto experience... and was able to successfully rebuild a 12a myself with help from this forum. Give it a go yourself, it is very rewarding as once done you feel you know every inch of the motor. Biggest barrier is the cost of the rebuild kit, which will be around $1100 US dollars. If budget allows can you order from the likes of Atkins Rotary in the USA? If shipping USA to Kenya is a barrier let me know and maybe I can help as middle man. This forum was so helpful to me that I would like to forward the help.

 

Many thanks for this suggestion and encouragement, this has given me food for thought...
I have contacted Atkins rotary. Budget fortunately is not an issue at all, we want to revive this beauty! Shipping should also present no problem.

J-P

 

I would suggest downloading the Atkins Rotary rebuild video from their site and watch it a couple of times. The video enabled myself, as a rank amateur with a box of bicycle tools and zero automotive experience, to rebuild an engine. Watching would give you an idea of if its something you wanted to tackle. It is very in depth but does have a couple of gaps that I discovered the hard way such as the rear stationary gear O ring and the need to cut down the side seals... but I can fill those in for you if you decide to go ahead. Main problem though is it assumes an engine in good condition so does not help decide if you should rebuild once you have it apart and can see inside but RX7Club has plenty of info on that part of the process. Again, total newbie here and claiming zero knowledge... except that this website and Atkins enabled me to rebuild an engine and more importantly.... to enjoy the process.

Currently on the same learning curve for the carb, but again weirdly enjoyable.

 

Thank you very much, I have done so and sent you a pm

 

Got it. Received your message. Talk to you there.

 

Can we What’sapp tomorrow? Today is my wedding anniversary and if I want to stay married I should stay away from car stuff!

Good idea to open up the engine before ordering parts. Three ideas that were useful to me.

When removing components from the block eg carb don’t take them apart any more then needed to take them off the block. Then put the entire component in a box on its own so everything stays organized and together. One box for carb, one box for pump etc.

Take a photo of every single screw, nut or fitting before you remove it, with a screwdriver tip on the item you are referencing so when you look at the pic a week from now you can remember what the pic was concentrating on. Put the removed piece in a zip lock bag, and write the time stamp of the photo on the bag as well as a description. This was much more effective than writing just a verbal description on the bag as you can them scroll backwards through your phone pics using the time stamps to match them.

The giant nut that holds the flywheel on is very hard to remove. Requires maybe 400 foot pounds to get it off and you need to prevent the flywheel from turning. An impact wrench works best, but if not available I used a chain and two bolts to tie the flywheel to the housing. If stuck at this nut let me know and I will see if I have pics.

What time tomorrow works for you?

 

I have watched the Atkins video, and it's really good! We're ready to tear the motor down tomorrow. I will post comments and photos when it's done.
Time wise we're on UTC +3 but for WhatsApp messages it doesn't really matter.
Enjoy your wedding anniversary!

 

Found a pic of how we chained the flywheel when we worked on its nut. One bolt from the back of the flywheel, the other to the rear iron. Chain links big enough for the bolt threaded section to pass through but not the bolt head. The first time we did this on an engine stand. This is the second time when the engine was back in the car and we realized we forgot a seal!

 

Thank you, we are planning to use a powerful air impact wrench, but this would be a good alternative if we struggle!

 

The wife ended up going in to work so I got time on my car! Finally got a carb flooding issue fixed and the car is running. Put me in a very good mood.

If a phone call would help I am available tomorrow 8am to 9.45am then noon through 6pm. I am on USA Pacific time... Looks like you are 10 hrs ahead of me. Let me know what time to WhatsApp call you.

One question did come to mind... Should I assume that since you are shipping from USA to Kenya that keeping them to a minimum would save to time and cost? If so, let me know before you place any orders. There are some items I found I needed during the rebuild that were not covered by the rebuild kits... so would be good to add them to your basket so everything ships together.

 

Great news about your carb, congratulations! You may call any time you want, when I sleep my phone is off anyway, so don't worry about disturbing me.
Yes reviewing the parts order together is a great idea, having to order more than once is a nuisance and extra cost...

 

Today we dismantled the engine, it went without a hitch, the impact wrench worked great. First impressions are mixed, the shaft bearing surfaces look good, the scratching on housings look manageable, but I am concerned about the slots in the rotor tips which appear to have spread, see close up pic. Does that mean new rotors are required? Every seal was well stuck with carbon deposits of course. Will post more pics when parts are clean, this will take a while... We are just starting a 5 day week-end here!

 

Found that pic of the edge seals on my vehicle. This was taken right when we opened up the engine, original parts in place. Does look like a much closer fit of edge seal into its slot. If memory serves me right it was almost a friction fit.... I could push the seal in and the spring would push it back out, but only just and you could feel a slight drag.

Good idea of yours on measuring the amount of spread. Post the results and let’s see if any of the really experienced folks here have a verdict.

 

Be careful when only using one rear bolt hole to secure the flywheel. I've broken the cast rear irons doing it this way. Best to use a flywheel stop.

 

Thanks Kansas. I had just been on WhatsApp with the owner of the Kenya Car and we thought best to keep our technical questions on this forum so folks with experience can stop me from having him do something dumb!

 

Now the parts have been cleaned, and I have tried to assess them, but since I have zero experience on this type of engine, I would very much appreciate your comments and feedback. To put things into perspective, the aim is to have a running car, which after restoration, will only see very limited use as it's part of a 35 classic car collection. It will probably take years for it to clock 1000 kms....

First the centre and end plates (we'll go from good to bad...)






Those only have light markings, where the engine has been stationary for ages, nothing can be felt by running your nail over the marks. I think these are fine.

Shaft

I have no photos as I left it at the machine shop, the pilot bearing is stuck inside and needs removing. It looks absolutely fine, but we will measure it and check it's within tolerances.

Rotor housings



This is the worse one, the other is also marked but more lightly. The scratches can be felt by running a nail across, but in view of what's expected of the car as explained above, I am hoping to get away with it.

Now the rotors




I used a 2mm drill bit and feeler gauges to assess the wear. In the middle, you can get two feeler gauges 0.20 either side of the drill bit so total width 2.4 mm.

Near the ends however it can be as much as two 0.5 mm feeler gauges so total width 3mm!

I feel those would be very useful as a paperweights, but scrap as far as the engine rebuild is concerned...

Again in view of what we are trying to achieve, I think sourcing a good second hand pair of rotors is the way to go, plus a rebuild kit from Atkins of course.

Waiting for your comments!

J-P

 

On closer examination, even the middle and end plates have score marks, would it be advisable to have them machined flat?

 

kinda surprised this hasn't been moved to the build section. anyway, if u check in the service manual u will find specs for all those clearances. and best measured with the seals in place. as for the score marks, if u can catch them with ur fingernail, then yes. there's step wear specs in the manual also.

 

I'm pretty sure your 12A rotors use 3mm apex seals .. so the ends of the grooves are sized correctly. There may be some carbon buildup in the middle area of your apex seal grooves. You can get a 3mm file or carbon scraper from Atkins to help clean those up.

Also if you still have some used apex seals that are clean and not warped, you can use one of those to check for gap instead of a drill bit. If you find that the apex seal grooves are too large, then you can swap in a set of Goopy oversized seals.

 

I believe foxed.ca is the best source for manuals? Wiser folks jump on if better sources.