Brief history:
have replaced pickup coil which requires removal of distributor gear
Rebuilt bottom end (Had to R&R crank, replaced all bearings)
Never have gotten timing right

Ok, seems like the best sound from my engine comes as you retard it all the way in one tooth of the dist, and as you advance it all the way on the next one. So what lm wondering is if mayhaps l put the distributor gear on 180* off. If I remember correctly, they arent symetrical. Therefore, l think that if l pulled the dist, R&R the gear 180* from present condition, it would give the setting l need. l wanted to check with you guys' opinion before l tried this.

FWIW l think that the old chain was so stretched that that is why l didnt notice the problem before the rebuild.

Clayton

 

if the distrib is out 180 your car will not run correctly..

here are two links to tech articles which i wrote on timing issues:
http://www.iroc-z.org/tech/distribut...ngdistrib.html
http://www.iroc-z.org/tech/distributor/settingtiming

good luck,
Colin



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Webmaster: www.IROC-Z.org

 

Thanks for the reply, but it didnt address the question. I was talking about the gear that engages the cam. The rotor on top was pointed in the general right area, but because the gear on the bottom was on wrong, it either pointed too far forward or too far backwards.

BTW I did swap the gear around, and it did help the problem.

Once again, thanks

Clayton

 

ok, lemme answer your original question as best as I can, and then I'll explain a couple of things

the distributor gear is held on the shaft by a roll pin, right? It does not matter which way the gear goes on as long as the snout of the gear is pointed down (obviously you can reinstall the distributor so that's a moot point). You cannot install the distributor gear incorrectly as long as the snout is pointed down and the roll pin is installed correctly.

Now, on to the next part.

You cannot 'stab the distributor one tooth off'. There is no such thing. You are only stabbing the distributor in such a way that the rotor will be advanced or retarded. This is why.

The car does not know if the engine has the rotor pointed at #1 spark plug when the engine is at number ONE cylinder top dead center. The car only knows (and cares) that at number ONE cylinder top dead center that the number one spark plug wire is directly OVER at the rotor at that time. Going by this logic you can have the rotor pointed at say, number FOUR cylinder, at top dead center and as long as when it is pointed there the distributor cap has number ONE plug wire over the rotor at that time, the car doesn't care? Confused? Don't be, just make sure that wherever the rotor is pointed at number ONE TDC, that you have #1 plug wire over it.

That's the reason for my installation tutorial about cutting a hole in your old cap. I am telling you to put your car at #1 cylinder TDC, see where the rotor is, stab the distributor in such a way that the rotor is where you want it (turning the oil pump if needed) and then use the old cap to get #1 plug wire perfectly located over the rotor so the engine will fire perfectly and run at 0 degrees advance or retard so it's easy to start and then set the timing.

Get it?

If I STILL didn't answer your question, I think you should email me so I can think it over more. Email: admin@IROC-Z.org

ttyl man and I hope I finally answered your question,
Colin

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Webmaster: www.IROC-Z.org

 

I am sure the gear on the dist. is symetrical. Otherwise, timing BTDC wouldn't be uniform throughout the cylinders. And if you had the dist. 180 degrees off, it wouldn't run. The best way to install the dist. is to mark a line from the center line of the dist. through the no. 1 terminal onto the firewall., bring the cylinder 1 to TDC on the compression stroke, and install the dist. with the rotor pointing directly at the mark on the firewall.

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'86 G-body Cutlass
Olds 307/TH350
Soon to be 377/700R4
To Beer or, not to Beer...

 

It took a while, but I think I got your question down.

The gear isnt symmetrical from what I can tell, it looks like on one side the roll pin lines up with the bottom of a tooth, and on the other side it lines up with the top of a tooth. I suppose if your adjustment travel was very limited (and it is on some cars, I dunno about yours) you could have a problem getting the timing set to where it needs to be before something on the top of the distributor physically hits something and stops. That sure must be some limited adjustment area you have there, but yes if you take the gear off and turn it 180, it will put the rotor inbetween the two places you have tried so far, more than likely halfway between.

 

i will refer to my previous post about the rotor being able to be at ANY place as long as the engine is at 0 BTDC on #1 cylinder and #1 plugwire directly over the rotor at that point

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Webmaster: www.IROC-Z.org

 

And I think thats why he is asking, I get the impression he thinks the cap isnt in the right spot. The gear is in fact different from one side to the other, so its possible he put it in backwards and now it doesnt line up where it used to. Most cars I have seen have plenty of space to turn the cap, maybe he doesnt.

 

Pull your dist and look at the gear. As Madmax said, it isnt symetrical. On one side the pin is between two teeth and on the other It is right below/above one tooth.

Also, on my car what was causing problem was the vacuum canister on the pas side contacting wires and valve cover. I guess w/ an ECM controlled dist it wouldnt have been as big a problem.

I agree that the car doesnt care where the dist is pointed, as long as the firing order is 1-8-4-3-6-5-7-2. So my #1 plug could be anywhere l want. l wanted to keep it as much as "normal as possible"

To reiterate, with the gear as it was originally, the "sweet spot" for adjustment was at the end of one tooth and beginning of the next. to see this in action, take yours off and swap the gear sides. After the swap the "sweet spot" was now all on one tooth of the dist. Thats my experience.

Clayton