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Re: 1983 RX7 S2 - Flo
Posted: Sun Aug 18, 2013 6:23 pm
by codge
Looks like an additional fuel filter up there above the engine. The normal one is at the fuel pump.
The exhaust header looks power sapping. Loooks like the thermal reactor is still in place.
The single belt looks the usual with the air pump removed.
Codge
Re: 1983 RX7 S2 - Flo
Posted: Tue Aug 20, 2013 10:07 am
by ian65
Interesting to see you've still got the ballast resistor wired into the leading coil. I see Janspeed also used the Microdynamics RX7 ICU2 ignition control module.... the early (pre swing arm wastegate) Elford Turbos used that module as well. It provided a rev limiter and retarded the ignition as the boost/revs increased. Elfords ditched it on the later models.
Re: 1983 RX7 S2 - Flo
Posted: Tue Aug 20, 2013 10:07 pm
by Tepper
Had a bit of a play with the car today, managed to set up a gravity feed to the carburettor. This doesn't change anything, it still won't idle making me think it could be blocked idle jets rather than cacked up fuel. I do think a carb rebuild is on the cards. However, I'm also thinking I might get away with replacing the filters once the carb's sorted rather than removing, cleaning and treating the fuel tank.
Another problem is that the RHS headlight doesn't work on dipped beam, but it does work on high beam. I've replaced the bulb, which made no difference, so I removed the stalks for the lights and wipers to check them. Haven't got round to actually checking it yet but I've got a nasty feeling it'll probably be a break in the wiring somewhere given that the LHS works fine.
During all this I've found LOADS of dodgy wiring, scotchlocks everywhere and plenty of non-standard connectors and crimps. There's also a mystery switch on the bottom of the steering column cowling, it's wired into one of the wires coming off the headlight stalk but I haven't a clue what it does. More fun and games.
With all of this I stand to be corrected, if I'm wrong please let me know!
Re: 1983 RX7 S2 - Flo
Posted: Tue Aug 20, 2013 10:15 pm
by DB RX63
Be really careful with the oil cooler, they do leak, but if you over tighten the fitting it may split the threaded insert on the cooler.
Some nice fella tried cure the oil leak on my Elford S2 oil cooler when I bought it and completely buggered the thread, it split in two.
I found a company to repair it, but it was difficult to find someone who could. For the life of me I cannot remember who did the repair, but it was very reasonable at the time (2005).
Re: 1983 RX7 S2 - Flo
Posted: Wed Aug 21, 2013 4:41 pm
by Tepper
Thanks for that, my oil cooler is indeed leaking so I'll be careful not to over-tighten it. What's the best way to fix it?
Re: 1983 RX7 S2 - Flo
Posted: Wed Aug 21, 2013 9:22 pm
by Tepper
Raising the bonnet today has resulted in questions, so many questions. For example:
Where should these connect to?
What's this solenoid valve thing for?
Is the brass thing with a single wire coming out of it the carb heater? If so, why is it wired into one of the terminals on the leading coil? Shouldn't it be connected to that wire hanging loose next to it?
Where should this hose go?
And finally, what's this and should there be something connected to it?
Answers on the back of a postcard... In all seriousness, any light anyone could shed on the situation would be greatly appreciated.
Re: 1983 RX7 S2 - Flo
Posted: Wed Aug 21, 2013 10:18 pm
by ian65
this one is the bypass for the redundant Microdynamics ignition control......
I can't see from the photo but is there just a wire that comes out of the back of it and loops back inside it again? This is used to disconnect the ignition control box without losing power to the coil.
is your ignition control module still wired into the leading coil? This will give idling problems if the leading ignition isn't working 100% The module breaks into the wiring for the leading coil and retards the ignition, knocks out every other spark during certain engine conditions and also limits the revs. If the whole thing is still fully working then happy days but if part of it isn't or if the high boost pressure switch is missing or other wiring messed up, it'll play havoc with your engines running. The best plan is the remove it altogether and wire the positive and negative sides of the leading coil back to stock configuration. I'd definitely make sure the ignition side of things is spot on before worrying about the fuelling or else you will have too many variables that could be causing the engine to run rough. The engine will just about run on just the trailing ignition alone but will run like a dog.... the leading does all the work, the trailing just picks up the emissions so the leading ignition must be working 100%
Re: 1983 RX7 S2 - Flo
Posted: Thu Aug 22, 2013 11:46 am
by codge
The Bottom pic: that solenoid connects to one of the rubber tubes out of the Air Filter.
That Brass Body thing.... not brass, plated steel. It's called the coasting richer solenoid valve and yes it should be connected through a bullet conn to the dangly wire. It's function is to momentarily rich the mix as you lift off the throttle.
Will I think you need a Haynes Manual on board here. Or find a friend local with another S2 to do a compare job.
There are quite a few connectors on the RX7 that don't go anywhere. Possibly the loom was for world market?
Re: 1983 RX7 S2 - Flo
Posted: Thu Aug 22, 2013 4:18 pm
by Tepper
Thanks for your help people, makes things much easier. I do have the Haynes manual but I'm not the best at deciphering wiring diagrams

I feel this car might be something of a crash course!
From what you're saying, it sounds like I might do better to put the ignition back to stock. I tried to google the microdynamics unit but I couldn't find anything, does anyone know where I might be able to find any information about it, especially how it's installed? I guess I could just strip it out and put it all back to how it is in the Haynes diagrams.
Re: 1983 RX7 S2 - Flo
Posted: Thu Aug 22, 2013 4:50 pm
by ian65
I'll pm you all the info about it later this evening
