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Discussion Starter · #1 ·
If the distributor is off by one tooth, would it run at all? (trying to go through the process of elimination here). New rebuild on engine, carb, etc. etc. Once started up, I've got a rough idle (like a lopy cam and the car shakes- but my cam is stock) and I've got tons of black smoke coming out of the duals (no H pipe). Carb is fresh rebuild 4100. Moving the dizzy to and fro does not clear the idle. The only think I can maybe think of is the dizzy gear being off a tooth.
All input appreciated!

Thanks
 

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Yes it will run, albeit crappy when one tooth off (ask me how I know). Get #1 cylinder to TDC on compression stroke and make sure rotor is pointing to #1 plug wire on cap. Also, double check your firing order.
 

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I have argued this statement for years, someone please tell me how a distributor being off 1 toth will effect your running, the distributor is a range devise, what range you put it in determines how it works, that is why you have movement, if you move the dist one way or the other, guess what? your movig it 1,2,3 teeth away from its original setting, either direction, so as long as the distributor is in the area of #1 when TDC is set up, you should be within range, then a timing light will complete the set up.

NOW!!
if the timing chain & gears are off 1 tooth, that, yes. that will cause an issue, because there is no way to adjust for cam timing.


I think you should look @ the valves as well, like wes said, if they are too tight, the engine will be pretty rough.

but b4 you dive into the engine, check the basics, make sure you have the firing order right,
what cam is in it? what engine? did it use the standard firing order or the 351 firing order? if it is a late model hipo, it will have the 351 cam & then your firing order is different.
does it feel like it is running on 1/2 the cylinders?
if it is a 289 or 302 standard F.O. will be 15426378
if it has a 351 cam , the firing order will be 13726548
 

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Discussion Starter · #6 ·
Thanks for the input.
The engine is the original 289 with a completely stock rebuild. The distributor has a petronix module (first type, not II). New cap and rotor, new plugs (I've double checked the firing order three times), New plugs (gapped), New, new, new, etc. My timing distributor was off when I first tried starting it. I pulled it out and re-stuck it (#1 at TDC and rotor at 1)- hit the ignition and instant start up but with a BAD (irratic) idle but it would hold the idle and not die. Also, as mentioned, plooms of black smoke out the exhaust. I stepped on the accelerator a bit and I can feel heavy hesitation (nothing was clearing up).

I'm going to double check everything that may be obvious- it was a long day yesterday. Perhaps I over looked something. And then I'll check the valves.

I've researched the distributor being off one tooth, and have found mixed opinions about whether or not this thing can be off a tooth and still run. Can anyone clarify the argument?

Again, thanks for all the input.
 

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I am the last person you should listen too...I am just a novice.

It seems as though your engine (being heavy and mechanical) was probably put together fine.
I suspect a carb...yes I read it has a fresh rebuild...can you borrow one from another engine and slap it on there and eliminate it as a problem...if you use a carb you know and see run on another engine and put it on yours...or put yours on another running engine and see if it runs fine.

Just an idea to help keep things simple from fuel supply first, then engine.
 

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Discussion Starter · #8 ·
MarkStang- My carb was rebuilt at Pony Carbs. Supposedly, they test run these before they send them back to you. I know things can go wrong between there and here so catching up with someone with a functioning carb is probably a good idea. Unfortunately, I don't have a carb near by to try this.
Thanks.
 

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Discussion Starter · #10 ·
Long story short- choke issues. I'm not sure if the choke piston got stuck, or ????? The butterfly wasn't moving freely- something was keeping it from opening up. It should move when depressed, and then flip back shut when released.

As far as the distributor tooth question goes. . . . from my experience in the last two days, I do not see how an engine will run if it's thought of as being "one tooth off". One tooth off meant my engine will not run, or start for that matter. If it starts, runs, and holds idle, I'd say the dizzy is in properly reguardless of how WELL it runs or idles.

All in all, everything seems good. Trans is shifting, engine accelerates smoothly, power steering is not leaking and is nice and firm (no play), brakes seems to be holding fine- as is the parking brake, and coolant is flowing. It got a little hot after the first run, but I think there may have been an air pockets in the coolant- seems a little better now. One thing for sure- I have to get rid of these Flowmasters!! These are TOO LOUD!
 

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"As far as the distributor tooth question goes. . . . from my experience in the last two days, I do not see how an engine will run if it's thought of as being "one tooth off". One tooth off meant my engine will not run, or start for that matter. If it starts, runs, and holds idle, I'd say the dizzy is in properly reguardless of how WELL it runs or idles. "

um, when you rotate the distributor in place to advance or retard the timing, what do you think your doing? your moving the distributor 1. 2.3 teeth advance or retard. so for you to say you do not see hoew an engine can run if the distributor is 1 tooth off, your quite mistaken,
I have had cars brought into my place with 1,2, 3 teeth off one the cam timing, & they run, they run lousy but they run
 
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