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-   -   12A super hard to start after rebuild (https://www.rx7club.com/1st-generation-specific-1979-1985-18/12a-super-hard-start-after-rebuild-1145867/)

workaholic 07-13-20 04:40 PM

12A super hard to start after rebuild
 
Just rebuilt 12a for my 83 rx7 gsl. I got it started a couple of times but it's alot of trouble to get it started. Already dove into the carb and fixed the float levels, bowl levels look good through the sight glass now. No vacuum leaks that I can find. I know the motor has compression because I got strong consistent puffs when I deflooded it. I'm thinking spark, but I know all of the plugs fire. Maybe they are firing weakly? Maybe at wrong timing? I stabbed the distrib with the nubs lined up when the pulley was showing tdc, but I've heard that the front pulley can get put back on wrong? I've burnt up 2 reman starters already and finally bought a new Bosch. I really don't wanna burn this one up.

workaholic 07-13-20 05:50 PM

Tested leading plugs near ground bolt and the arc was orange instead of the expected blue. New plugs(br8eq14), wires (ngk), cap, and rotor. Is this a weak spark issue?

GSLSEforme 07-13-20 08:54 PM

You NEED!!! a fully charged,good battery to start a rebuilt rotary. Be sure your cables positive and negative are clean(bright) and tight. Be sure your body ground is present at driver apron and it is also clean and tight. Did this car run previously with this distributor? Are your cap/rotor/wires/plugs all new?

Check static engine timing by removing inspection plate at right rear of engine and turn engine til flat of flywheel lines up with side of engine like in pic. This is TDC for rotor#1. If pulley is installed correctly,the marks will line up with pin in front cover,if not,remove and orient such that they do. With engine still in same position,remove distributor and line up marks on shaft and body and install in engine with adjustment bolt in middle of slot like in pic. Your engine is now mechanically timed and should start and run. You can set ignition base timing with a timing light after engine is running.
https://cimg9.ibsrv.net/gimg/www.rx7...7c8e5b0070.jpg
https://cimg1.ibsrv.net/gimg/www.rx7...26aa47788a.jpg
https://cimg2.ibsrv.net/gimg/www.rx7...96c68daad3.jpg
https://cimg2.ibsrv.net/gimg/www.rx7...add4934112.jpg
https://cimg9.ibsrv.net/gimg/www.rx7...426fcb12d2.jpg

workaholic 07-14-20 04:49 PM

I'm running an aftermarket flywheel with a counterweight from an auto. When I was testing the plug arc, they were firing right about when the gusts of compressed air were coming from the leading plug holes; would that mean I'm close?

workaholic 07-16-20 04:35 PM

So close today. Put new coils in (MSD 8222) and dialed back the idle air screw about 2 more turns. It was "running" with the starter spinning it (as in there was ignition) but when I stopped spinning the starter it died. Starter get slow when it's too hot so I'm letting it take a break. I feel really close to getting this thing to start somewhat dependably. I always said, "rotaries will run no matter what, sometimes they'll run like shit, but they'll still run"; this thing tryna prove me wrong tho.

LongDuck 07-16-20 06:55 PM

Dude, coils won't matter if your timing is too far off to light the engine.

Go back up to GSLSEforme and his advice on removing and setting the distributor correctly, then go from there. Until then, you're just wasting your time and starter.

Chimby 07-17-20 12:15 AM

I agree with the gentlemen. Sounds like timing is off brother.


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