won't start after changing distrbutor cap and rotor

[mitmaks]

Rotor only goes on one way you crazy people!

Are you serious? Not really, it can go on multiple ways. That's why its important to note how it was pointing before taking it off.

[Ryan]

I have five (5) distributors I have created in my garage. I'm quite sure. If you examine the rotor carefully, there is one side that is slightly wider than the rest. If you examine the shaft it goes onto, there is on slightly wider flat spot. Another way to find it is to look at the thickness of metal between the flat spots and the screw bore, and look for the thinnest one. The ignition end of the rotor points that way. If you cram it on any other way, you're doing it wrong.

[_-Night-Shade-_]

Can somebody finally confirm or deny this already? When I did my KLZE swap with the help of JWMX3, when we swapped over my 94 disty he also said that there's a 50/50 chance that it's off because the rotor can be 180 degrees backwards. He's done millions of engine and disty swaps so I'm sure he knows what he's talking about. Plus IIRC the rotor does look the same on both sides, and I've got some spares I'll have to take a look at. But anyways, I don't wanna hear about some hypothesis from a guy that's got 5 spare distys sitting in his garage (no offense), I wanna hear it from people who've actually done it.

[Ryan]

Actually you're right. I have only verified this for 92-93 distributors.

also, my mechanic (20+ years (not a million) of Mazda ONLY experience) tells me that they all only go on one way. I would consider this a decent argument from authority, as he has been replacing ignitors, coils, distributors, caps and rotors on these cars for much longer than the vast majority of you have owned this car. He's seen the problem from the first ignitors that failed, when Mazda produced spare ignitors.

Although, its not rocket science for anyone to rediscover how it should be set up. Put a cyl at (a little before) TDC, and line the rotor up with that.

And at least I'm out 'theorizing' instead of waiting for someone else to get some information...

[SE MX-3]

95% sure that the rotor can only go on one way. i will double check when i take it apart again and let you guys know for sure.

[Daninski]

This post reminds me of that Bla Bla Bla video. lol

Check that your wires are fully seated into the cap. Pull a spark plug out and crank the engine and watch for spark. If you try all the suggestions here and it still dosen't start sell the car to Ryan. He enjoys a challenge. lol

[mitmaks]

also check your coil with a multimeter.

[Newfie_dan]

mine is a 96 and it will in fact go on in different positions, mind you my rotor is from a mx6 as well. The 1.8 rotor does not fit my distributor.

[SE MX-3]

on my distributor, the rotor only fits on one way. as ryan said, there is one side on both the rotor and shaft that is larger than the others. again, this is for the older distributors, so the 94+ may be different.

back on topic, my car will start now although it is still running very rough. 90% of the time, while driving, the car will sputter and lacks power. 10% of the time the motor runs normally. i noticed a hairline crack inside the distributor when i had the cap off, could this be the cause?

i plan on changing out the plugs and wires as theyve been on the car since i bought it. any other suggestions?

[Daninski]

As long as the crack dosen't go right through you should be ok. It could be a manufacturing fault. usually electrical issues with wires and ignition gets worst in wet weather or on a damp morning but will be fine during mid day when it's dry. You could check your TPS and reset your idle (top of TB) as well.

When the cars acting up try spraying your ignition wires with WD40. If the engine smoothens out it's obviously bad wires.

[Ryan]

WD40 is flammable, Danny. So unless you want an engine fire, I'd suggest a silicon spray.

[SE MX-3]

the problem is worse in wet/damp weather. ill change out the plugs and wires, thanks for all the advice guys.

[Tunes67]

If your plug wires are really that old.. you probably have arcing to ground at various cracks in the wires (these cracks arent always visibile to inspection either) this will result in constant misfiring and would explain the loss in power and the rough idle. Easy to check for.. wait till night time with no light near the engine bay. Start the car with the hood up in pitch black and watch for flashes of light around the plug wires where they are close to any metal. The flashes will be faint so let your eyes adjust to the darkness before doing so. The more flashes you see.. the more places the arcing is occuring and the rougher the idle will be.

Tunes67

[SE MX-3]

Spark plugs and wires have been changed, and there is a noticeable improvement in the way the car runs.

However the engine still isn't running properly. After I changed the plugs/wires the engine backfires a idle/low RPMs. I know for a fact that the timing is off and I'm sure its contributing to the problem, but I think theres more to it than that. I do not have a timing light, but I tried to adjust the timing by ear. No matter where I set the timing the backfire is still there. Advice?

[Newfie_dan]

Backfiring can be a direct result of the timing being out so I would deal with that first prior to attempting to diagnose the backfire, if it continues to backfire then you are getting excess fuel dumped into the exhaust system hot exhaust temps when mixed with fuel hits the air outside = backfire.