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Old 05-27-2005, 03:20 AM   #26
R@nger
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So if I have this straight your 8degrees BTDC is the number 4 notch mark on your timing tab? I think I read in my haynes manual that every notch on the timing tab equals 2 degrees...this that true?
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Old 05-27-2005, 03:32 AM   #27
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I don't know for certain. It sounds correct tho. Remember 8 degrees BTDC would be the notches CCW before the Zero mark. Put the #1 cylinder at TDC and put your timing mark at zero. After it starts, you can then rotate the distributor to 8 degrees BTDC. Main thing is to get it started first.
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Old 05-27-2005, 03:41 AM   #28
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Ok cool...question though, with it being that far off would it make the spark really weak..weak enough not to start? I'm just wondering if this is my whole problem..the timing was just to far off..which I have no clue how it would have done that. Since it was fine before.
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Old 05-27-2005, 03:56 AM   #29
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It could possibly make your spark appear to be weak since it is not firing when it is supposed to. I'm not an expert on that. Give it a shot. If it doesn't work, try replacing the pickup coil like what was suggested. Are you still working on it now?
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Old 05-27-2005, 04:12 AM   #30
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No unfortunately its a bit late...I tend to be loud when working on the truck . Should have heard me when my rachet slipped off the nut while I was turning the crank lol...my poor knuckles. I'll start working on it again tomorrow morning.

Thanks for all the help and I will post after I re-adjust the distributor.
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Old 05-27-2005, 04:20 AM   #31
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Hope it works out for you.
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Old 05-27-2005, 06:27 AM   #32
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I a little late but if your timing light is flashing you have spark to the plug. It sounds like your wires are off by 1 hole on the top. Put the #1 wire over the rotor at TDC and wire from there.
I would also check and make sure you have 12v when you are cranking the engine and not just in the on position.
If the truck was running and you did not pull the distributor, To start it I would not pull it till I got it running again. I would pull the TACH lead off the distrib to make sure it wasn't loading. With the plug on the end of a wire and the plug grounded, cranking the engine the blue arc will only be between the gap on the plug tough to see on a sunny day but at night you should see it clear.
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Old 05-27-2005, 10:06 AM   #33
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Like the rest said-if you are getting spark pickup is OK. Rotor will be off #1 if you have your timing advanced. Look at it this way--if your timing is set at say 8* BTDC the rotor will line up with the #1 post in cap when the timing mark on balancer is lined up with the 8* mark on timing tab. If you rotate the timing mark on balancer to 0* (TDC) the rotor will already be past the #1 post in cap as it should be.
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Old 05-27-2005, 05:31 PM   #34
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Thats the thing though, I put the crank where my timing was set which for some reason it ran best at 16degrees BTDC...so the 8notch on the timing tab. When I put it there it was even farther away than before. I had it at TDC so 0 and when I cranked it over to the 8 notch the rotor went farther away. I have the plugs set up so that the number one plug is 1 post clockwise away from the box that comes out that you plug the battery and stuff into...so there is one post inbetween the battery and tach terminal and the #1 post.
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Old 05-27-2005, 06:10 PM   #35
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SHES ALIVE

I loosened the distributor and turned it so that it lined up to the rotor at TDC. Then I cranked up the truck and it started and ran!!! Heres the problem though...I got out the timing light and saw that the mark for the timing is way way to the right not even close to the timing tab. If I turn the distributor clockwise to move the timing back towards the timing mark the engine dies. Its running smooth but its not running with any power..at least it doesn't sound like it. It runs better the farther I move the distributor counterclockwise but I'm can't turn it anymore...and when I do turn it more it also moves that much farther away from the timing mark...which like I said it now very far away. Could my timing chain have slipped..or is it time to replace it? I just don't get why the timing would change that drasticly.

Regardless...I can't get the smile off my face.
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Old 05-27-2005, 06:31 PM   #36
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I would make sure the vacuum advance hose is disconnected when you are checking the timing. Then set the #1 to TDC again and see where the rotor is. It sounds like when it was installed it was put in like the old point distrib which is 1 plug hole off a newer HEI setup. At this point you could rewire the top plug wires so you can adjust the distrib. It doesn't matter where the wires are as long as plug wire 1 is at the point where TDC -8*-12* is where the rotor is. You just have to remember and do all the work on it or you will drive a mechanic crazy.
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Old 05-27-2005, 06:37 PM   #37
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I didn't put the distributor in...the previous owned I believe and from how I've seen other things done I wouldn't be supprised if what you said isn't exactly true. I'll try doing what you said and moving the plugs over one. Oh and when I checked the timing I had the vacuum advance off and plugged the hose.

I just don't get why all of a sudden the timing would change so drastically..any thoughts? The timing hasn't been changed since it quit running so nothing changed.

Oh and what did you mean by this
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Originally Posted by dwaite72lnghrn
You just have to remember and do all the work on it or you will drive a mechanic crazy.
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Old 05-27-2005, 06:59 PM   #38
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I meant if you wire the dizzy halfazd then nobody but you will know how its done(AKA the previous owner).
My best guess as to what happen was you had a coil or module failure, pulled it apart and put it back together where you expected it to be and it was wrong because the guy that put it in had it off 1 hole. You can get in real deep quick if you don't label things when you pull them apart(keep masking tape in the glove box and a pen,write on the tape then peel off the roll). This is because of 35 years of tinkering, splicing and rigging by countless number of people.
If you can get it running off 1 hole and adjust the timing. At that point you can then pull the dizzy and put it in so everyone will be able to work on it.
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Old 05-27-2005, 07:02 PM   #39
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Wow man..dwaite you hit the nail on the head. I went out there and moved the #1 post over to the right one then realigned the distributor so it and the rotor would line up on TDC. I then cranked it up and with the vacuum advance off and plugged the timing was at 0BTDC and then I just turned the distributor and the engine came alive. The only thing is that I set it at the 8notch so 16 BTDC and its still not very responsive. Any way to fix this considering that its not even supposed to be 16degrees right?

Thanks alot for the suggestion and thanks to everyone else thats helped me. You have no clue how grateful I am...thanks.
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Old 05-27-2005, 10:31 PM   #40
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The most I have ever seen on a timing flag was 12* is this thing a stock flag for your timing mark? Most have like a 4 and a 8 and maybe 10-12 mark which is * BTDC so if it was at the mark labeled 8 it is 8*. Does your timing light have a degree wheel on it? That would be the only way you could actually see the 16* on a stock damper. With the degree timing light you turn it to 16* and the timing light should flash at 0*.
This is also the only way to see when your mechanical advance comes in full at what RPM, run the rpms up till the advance stops moving and turn the timing light wheel till it registers 0* flash and read the wheel this is your max mechanical advance at that rpm.
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Old 05-27-2005, 11:13 PM   #41
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Um everything is stock...the timing tab goes up to the number 12. I'll take a picture of it.

As far as the timing light, nope its just an old I think craftsman timing light.

Heres a link to a picture of my timing tab...flag..whatever it is hehe.
http://i4.photobucket.com/albums/y13...n/IMG_0058.jpg

I have it timed right to the 8 mark on that timing tab and the engine isn't very responsive. As in when I give it some quick throttle it isn't right there its slugish. Before I could give it some quick throttle and it would be roaring and waiting for more.
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Old 05-27-2005, 11:32 PM   #42
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So if the light is on 8* then you have 8* timing which I think was stock on a GM350 back in '71. About 1/2" past the 12 is about 16*. This would be about max as the engine will run Hotter and start to ping when you step on it(very bad thing). If no work was done to the engine I probably would not go above 12*. Again run the rpm's up while you have the light on and see if the mechanical advance is doing its job as the revs go up it should move the light farther back on the damper, It should be smooth and no jumps in it and should come right back smoothly when the revs drop. If it jumps or seems to stick you will need to greeze the mech advance under the rotor in the cap. It is very common for the mech advance to rust and stick which make constant timing adjustments as the weather changes and they decide to unstick now your timing is off again. good luck
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Old 05-27-2005, 11:34 PM   #43
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Ok the engine is a 77-79 I believe and yes when I give it some gas you can see the mechanical advancing working nicely. I'll still throw a little grease on the springs and around some of the other parts of the mechanical advance.

The number on the back of the block is this GM 14016379.
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Old 05-28-2005, 12:35 AM   #44
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You would not even believe my luck.....I just went outside and hooked my tach back up to see if it would work. All I had to do was plug the spade connector back into the tach on the distributor and then plug the power back into the power source I was using. I did that cranked the truck and it wouldn't start. I rolled my eyes and got out the timing light because it wasn't even attempting to fire. I hooked it up to a couple plug wires and none of them made the light flash. So I got out my multimeter put the ground on the battery neg- and the positive on the battery in wire that connects to the distributor..nothing no power. I unplugged my tach tried again just to be sure...nothing. Now my distributor isn't getting juice. I swear I fix one thing and I no sooner fix it than something else breaks.

So...I guess now I'm tracing that son of a beast distributor power supply back to whereever its not getting power and try and fix it. This blows
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Old 05-28-2005, 01:29 AM   #45
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If you don't want to trace it out, or if it looks like it needs replacing, you can always just run a completely new wire. 10 or 12 gauge wire is fine to one of the unfused terminals on your fusebox...
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Old 05-28-2005, 01:39 AM   #46
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I may just do that, thanks.
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