clean

Hey,
I'm from London, ON, and I'd like to find a mechanic from this area that I can take my car to for some work (whenever it gets beyond me.. which happens often). I need my idle/air mixture adjusted, I've played with it, and it seems okay.. but not great, and I want it set right, but I'd like to find someone who knows what they're doing, I don't even know if this is something I can take to an average garage. Anyway, if anyone's from London, and you know of any shops around here, let me know.
Thanks.

SilverRocket

I've heard really good things about Mazdee's here in Toronto, and from talking to them on the phone they seem to know their ****. It's worth the drive to find someone who knows the motor.

Do you have a Haynes manual? If not, you should get one.

Setting your idle mixture is not too much of a challenge; just turn the screw clockwise (lean) until the engine stumbles, then back it off about a half turn or so.

This is what I do, it seems to work well, but others here who are more knowledgeable may have better advice.

RXcetera

Good shops? Well, mine closed down last year . Seems like ever since I closed shop, RX7s have been becoming more and more popular. Oh well... drop me a line if you're ever around Ottawa and need some work done.

As far is the idle mixture is concerned, provided your carb is working properly (I'm assuming you've got the 4 barrel), it shouldnt be difficult to get your car to idle properly. But, many little things can go wrong and render your idle mixture adjustment almost useless. Provided everythings is okay, here's what I recomend: Tighten the screw clockwise all the way (dont over tighten... you can damage it!). Now, turn the screw counter clockwise 3 full turns. Start the car and listen carefully... Uscrew/screw the screw slowly until the engine runs as smoothly as possible... its almost impossible to get it perfect, but take your time. If you find yourself having to unscrew/screw more than one more full turn in or out, chances something else is wrong. If you're having a hard time getting it just right, try unplugging the vaccuum advance plugs (green, orange). BTW, its IN rich, OUT lean. Good luck!

SilverRocket

Hey RXcetera, I lived in Kanata until 2 years ago when I moved away to school....

What was your shop called?

Can you forgive my ignorance and explain the intuition between IN being rich? I thought that when I turn the screw clockwise (IN) and the engine starts to stumble and die, that is because it is not getting enough fuel (ie lean). When I turn it the counter-clockwise (OUT), the engine gets more gas and thus runs smoother (rich).

Am I misunderstanding which way is in/out?

Oh, and... how much bearing does the idle mixture actually have on the a/f mix at mid-high rpm? I'm sure everything works together, but I thought the jets had more to do with that?

Thanks

clean

Hey, I've adjusted it.. it's actually not that bad right now, but it's not good. I found that before I started playing with it, I had a whole lot more power than I do now, I think it's running a little lean.. but.. well.. I'm not sure. I'll try what you suggested, about adjusting the screw, but the problem I face is, finding the balance between the two screws. I don't know how to get them both adjusted right.. at the same time.. Any tips.

SilverRocket

I was working on my car tonight, and fine tuned the a/f a little bit... made some power!!

For me, I already set my idle at 750rpm a while back, and I haven't messed with it since.

Here's what I did tonight:

1) I turned the screw right until the motor starting stumbling.
2) I turned the screw left about a half turn.
3) I very slowly kept turning the screw left, listening very carefully to the engine.

I spent about 20 minutes, listening to the motor (taking breaks when my loud as hell e-fan clicked on), trying to hear where it was running the smoothest. You know how the motor kind of "boom-boom"s a little every so often? While I tried to listen for the a/f where this was happening the least.

Anyways, I went out for a spin, and it seems to pull a little harder.

However, I also cleaned my carb. cleaned my brakes and some other little things tonight, so I suppose it could be anything else or just my imagination (but I don't think so...) It seemed to make a difference.

By the way, what do your plugs look like? You can tell whether you're lean or rich by the color (ie brown is pretty good, black is rich and wet black is way too rich).

Sorry I can't give you better direction with the other screw. I think you should try different things and see what works best; I think it's unlikely you'll detonate or anything like that unless you set it ridiculously lean.

clean

Hey, well.. I think it's set 'okay' right now, but which of the screws are you talking about. They're both on the driver's side, at about the center, and the other's back 6 inches from there. I think the one in the center is air, and the other is gas.. I also don't know if the screw placement changes from year to year, or if I have a wierd carb or what. My car's an '83..

SilverRocket

You need to get yourself a shop manual partner... it will explain all this stuff.

I believe there's a screw for mixture (air/fuel) and a screw for idle speed.

The mixture screw on mine is the shiny one in the center on the driver's side, easy to see. But yours might have a cap on it so you can't screw with it, if nobody has removed that yet.

I don't remember exactly where the idle speed is, I think right above/below, but it might vary between some years.

What is your idle speed? It should be about 750.

RXcetera

Ok, ok, I'll be your shop manual lol. The IDLE MIXTURE screw is at the bottom of your carb on the drivers side. It has a big "star" shaped head. The IDLE SPEED screw is to the right of it. It has a "flat screwdriver" type head.

Its kinda hard to explain how these work without drawrings, but I'll give it a try... The IDLE MIXTURE screw is basically a "spike" that you either push into (tighten) or out of (loosen) a hole in the carb. This "hole" is actually an air passage that is drawing air from outside the carburetor. By turning the screw clockwise, you are restricting the size of the hole thereby reducing the amount of air allowed in the idle circuit (=rich). Turning the screw counter clockwise increases the amount of air in the circuit (=lean). This screw only adjusts the air/fuel mixture AT IDLE. Turning this screw will not provide any perfomance gains... sorry guys .

The IDLE SPEED screw is a much more straightforward device. It acts the same way your gas pedal does... it controls the amount of mixture that is allowed past the butterflies at idle. thereby increasing or decreasing engine speed at idle.

CLEAN, set your idle to 750~900rpm with the IDLE SPEED screw BEFORE doing any IDLE MIXTURE adjustements. Once you've adjusted the IDLE MIXTURE screw to your liking, reset your idle back to 750~900rpm with the IDLE SPEED SCREW. I strongly suggest you disconnect the GREEN and ORANGE plugs (the 2 first ones on the left) before you do any adjustments... While you're at it, leave them unplugged when you're done. You'll gain some power with this (very) simple mod. Just remember to plug them back in if your car ever gets smog checked.

Silver, the shop was called Unipro/RXcetera. It was in Gatineau. I still work on rx's part time, but now everything's in my garage at home... no hoist.

SilverRocket

Thanks for all the help RXcetera. I didn't seriously think that adjustment had much to do with performance, but hell something I did last night seemed to work

For some reason my car always seems to feel faster and tighter after I spend time on it. Maybe I just appreciate it more?

RXcetera

Mine always runs awesome after I spend a couple hours washing/waxing it! What's up with that?

SilverRocket

Your rex is not just a piece of machinery, she need love!! When you spend time keeping her spotless, shiny, and in perfect working order, she rewards you tenfold. But if neglected or unappreciated, she'll bite back...

Denny

Well, Wrench-hands....

It's called "Interpersonal Dynamics." In layman's terms that means personal interaction with something whether it be inert or living. People talk to their dogs, cats, horses, birds, plants, ball mitts, hockey sticks, guns, fishing rods, boats, and so on. We talk to cars, and because we shed blood, skin, muscle, money, and most of all time, on 'em they develop their own personalities, and believe it, or not, Souls. I've had cars that have no Soul. Not that I didn't work on 'em, they just didn't seem to respond...They stayed inert. Then there's others that somehow seem to develop a "direct wire" to your being. Driving, working on, polishing, or just being near 'em kind of puts you in a "zone." Usually this is a singular activity, but there are cases where a whole specific vehicle model seems to come from the factory already equiped with Soul. I like to think that it's because the guys at the factory "Know" what and why they're building the vehicle for, and that extra "Knowing feel" goes into every part. A number of older British sports cars have it (but then lost it), Porches, Corvettes, early Z/28's, early 'Stangs, and so on. You can tell which ones do, because they become "Collector's Items," or develop their own "faithful following," and people start giving them personal names, usually female names. So it is with the RX-7, especially our 1st gens who have somehow survived through previous owners, mechanics, abuse, and neglect, to end up in our tender possession. We lavish what we can on them, and they seem to respond in kind. Ever seen someone's reaction after they've driven their first Seven? It's really quite an enjoyable interaction, or dare I say "Love affair?" All in all, it's a beauty way to go!

As someone said, "You're born, and you die. In between you work on cars..." To which I say, "That's a wee bit of the 'All Right!"

A tip of the 'ol Stetson,
Denny, from the abandoned corncrib....

RXcetera

That was beautifull... I was honestly moved by what you wrote. I'm leaving work...and I'm WAXING MY CAR! Love is in the air!

Pele

iTrader: (28)

Lower wind resistance.

Amur_

I went to Mazdees 2 summers ago when the rotary in my first RX-7 ate itself. They were excellent. They were also 2 hours away on the 401. I'm in Kitchener, they're (now) in Pickering.

You want Paul's Tire and Auto here in Kitchener. They're right off highway 8 above the 401 interchange. The owner races an '88 TII and their #1 rotary mechanic drives an FB and really knows his s... ('scuse my enthusiasm.) I refuse to take my FC anywhere else, even for small jobs. They've done an engine xfer for me and a lot of other work. They've also got a few RX-7 wrecks around the lot for parts.

Mazdees - (905) 619-8813

Paul's Tire and Auto - (519) 748-1081