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-   -   First startup fail - Sanity Check plz (https://www.rx7club.com/1st-generation-specific-1979-1985-18/first-startup-fail-sanity-check-plz-886500/)

ducktape 02-08-10 04:37 AM

First startup fail - Sanity Check plz
 
What a crappy Super Bowl Sunday. Was watching the game while trying to get this thing to run. Me and the Colts failed.

Filled the trans and motor just before kickoff, lined up the TDC mark on the pulley and dizzy and cranked it over. The direct-fire ignition seemed to be working right, but it still wouldn't start. I thought I had the trailing wires hooked up wrong, but instead of looking at the FSM I decided to disconnect the trailing altogether. Bad move. Combined with a weak starter and a Dellorto that is jetted for a 13b, the car did little but backfire and send clouds of fuel vapor into the garage.

After hours of flipping the distributor alignment 180 degrees and back, I realized the TDC mark on the 2nd gen pulley I had installed was in the wrong place. I had no idea what the correct position of TDC since I wasn't 100% sure in which of the 4 directions the TDC mark was supposed to go. Also, since the flywheel on this motor is aftermarket, there was no way to confirm from the side cover.

I opened the top cover as some have recommended and located the counterweight to the spark-plug side with the corner of the counterweight pointed up. I then assumed the pulley would be in the right quadrant, and bolted the old pulley on and rotated it slightly to the right-side timing mark:

http://www.bfhracing.org/duck/timing4.jpg

http://www.bfhracing.org/duck/timing1.jpg

I installed the dizzy with the timing mark pointed at the notch, and tried to start it again. Again, I failed. I flipped the dizzy 180 degrees and back some more. Finally, I disconnected the direct fire and connected the trailing ignitor, coil, and wires up to the leading side of the dizzy.

http://www.bfhracing.org/duck/timing3.jpg

Finally I came to my senses and opened the FSM, found I had the wires connected backwards and that there is a guide on the rotor to indicate TDC postition L1.

http://www.bfhracing.org/duck/timing2.jpg

The (top) blue mark and arrow on the rotor indicates the cap position L1 at TDC when the dizzy is installed correctly. No more flipping the dizzy around.

At this point it was late, and the game was over. The battery was flat, and the starter was hot. I called it a night, taking a short video of the failure.

http://www.youtube.com/watch?v=y7djCw7iSZU

I ordered a new starter tonight, not sure if the battery will be able to hang or not. I need to rejet the carb.

I'll probably try to hook the direct fire ignition back up tomorrow with the trailing in the correct position, and try again.

So for the 12a gurus, does this timing configuration seem right? Anything else i can do to try to get it started?

acekid7 02-08-10 09:51 AM

dam man. Good luck i wanna see that thing started.

©ØÐËߣüË 02-08-10 11:59 AM

on the main pulley, if you take out the bolt, you should be able to see the key way. the little piece that holds the pulley in place. turn it so it at 9 o clock. then go and set the rest of your marks.

Hope this helps.....nice build

ducktape 02-10-10 08:34 AM

That helped. Confirmed the the keyway mark is at 9 o'clock, and the counterweight is where it's supposed to be. Confirmed the timing is spot on TDC with a timing light.
Still won't start, but I think it's just a weak starter at this point. Should know by the end of the week.

installer67 02-10-10 10:01 AM

are you using the J-109s? or the hei igniters? If your using the hei igniters, try to swap polarity. Some of them seem to be - triggered. I ran into that same prob with mine and took forever to figure out.

ducktape 02-10-10 11:56 AM


Originally Posted by installer67 (Post 9795088)
are you using the J-109s? or the hei igniters? If your using the hei igniters, try to swap polarity. Some of them seem to be - triggered. I ran into that same prob with mine and took forever to figure out.

Using a J-109 for trailing, and a gutted/soldered J-109 as a trigger for the MSD on leading. It's getting spark now at the appropriate time, it's just not starting.

I'll let you guys know how the new starter helps when it gets here.

trochoid 02-10-10 02:32 PM

De-flood and clean your plugs. I bet the starter is fine.

Jeff20B 02-10-10 04:06 PM

He probably needs either an automatic starter or a covnerted 6 volt starter. The automatic starter has a really long housing (longer field coil windings) and is self supporting at the flywheel gear. I hear it lasts longer too because it was designed for 12 volts. About a hundred bucks.

ducktape 02-12-10 06:01 PM


Originally Posted by Jeff20B (Post 9795938)
He probably needs either an automatic starter or a covnerted 6 volt starter. The automatic starter has a really long housing (longer field coil windings) and is self supporting at the flywheel gear. I hear it lasts longer too because it was designed for 12 volts. About a hundred bucks.

Had planned to run a 6v starter at 12v, but the bindle-shaft and gear were wrong. Ordered a high-torque starter, supposedly 30% more RPM. It's obvious the bus starter I have is shit. It runs down the battery immediately, gets hot to the touch, and won't crank anywhere near acceptable speed.

I tried it a few more times, and everything is as it should be. Timing gun shows the Leading is hitting when it is supposed to and the plugs come out dry. I just don't think it's moving fast enough to start. Tried pulling the fuel pump fuse and running on starting fluid, didn't even pop-over.

Since the UPS guy didn't bring me anything today, I guess I'm going to have to wait 'til Monday to try again. Might go see how fast my friend's stock 12a spins with the ignition disconnected...

Jeff20B 02-13-10 01:37 PM

Good idea. I've also found it's a good idea to have a "known" engine at the beginning of your project so you know how it ran in the donor vehicle. So far I've tried a fresh rebuild in my baja and an old used engine. The used one was by far the better choice. So this time around I'm going with a recently built engine from my daily driver that I know how it runs, and I'm building a new one specifically for the baja, with the features I want, and breaking it in in a "known" car for at least 500 miles. This way I will know what it takes to start cold and hot, how hot it tends to run under various conditions, and lastly how much power I can expect to get out of it, and where that power exists through the RPM range.

So to sum up, I'm throwing in a used motor from my daily driver and building a purpose-built engine and carefully breaking it in in something else so I can get to know it before it needs to perform. I think that's a level headed approach. Wish I would have done this first. Oh well, you learn as you go.


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