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Discussion Starter #1
I know where the #1 post is in the cap and can mark that on to the distributor body, then remove the cap and install the rotor pointing at the mark

I can set the engine up to #1 TDC

now what I need to know is, should the #1 post be directly in the center of the rotor head?

Or should the rotor head be just about to start contacting the #1 post?

I know that I can just adjust the distributor accordingly either way as long as it's in the general region of the #1 post until I achieve the correct ignition timing with my gun,

BUT I want it to be as close as possible because I'll be firing up the motor for the first time after being torn down and the new cams need to go through the break in procedure by running the RPM at 2k (immediately) for 30 minutes. Any time idling during the break in can damage my cams

So I can't be screwing around with the timing light during the cam break in

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I know where the #1 post is in the cap and can mark that on to the distributor body, then remove the cap and install the rotor pointing at the mark

I can set the engine up to #1 TDC

now what I need to know is, should the #1 post be directly in the center of the rotor head?

Or should the rotor head be just about to start contacting the #1 post?
Kevin -you have a '99, right? Is yours 4-cylinder or 6-cylinder. Anyway, I've had distributors out on both engines.

The rotor head be just about to start contacting/be under the #1 post.
 

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On my daughter's '98 Pathfinder with same V6 engine, the distributor hold-down bolt is NOT in the center of the distributor groove when timed correctly, it's near the end.
 

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On my daughter's '98 Pathfinder with same V6 engine, the distributor hold-down bolt is NOT in the center of the distributor groove when timed correctly, it's near the end.
Same with my '01 Frontier: IIRC the slot on the distrib is all the way towards the windshield, so the bolt itself is located in a position where the distributor could only be moved counterclockwise towards the front of the truck.
 

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Discussion Starter #6
Same with my '01 Frontier: IIRC the slot on the distrib is all the way towards the windshield, so the bolt itself is located in a position where the distributor could only be moved counterclockwise towards the front of the truck.
I would think if you move it a tooth then you could still be in spec but bring the adjustment closer to center

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Same with my '01 Frontier: IIRC the slot on the distrib is all the way towards the windshield, so the bolt itself is located in a position where the distributor could only be moved counterclockwise towards the front of the truck.
Yeah, now I remember: on my daughter's '98 Pathfinder - she bought an aftermarket distributor for $82 - I had to "lengthen" the slot about 1/16th of an inch to be able to reach the factory timing.
 

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I would think if you move it a tooth then you could still be in spec but bring the adjustment closer to center

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Yeah I thought about it but I wasnt exactly sure if I should shift the teeth one to the left or to the right. I left it all at factory. Im going to attempt to manually time the engine at some point, hopefully it doesnt bite me in the ***. (but i could just do what Cusser did and grind out the notch a bit more if necessary)
 

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I replaced the distributor and can't get it started. the marks I"m using for TDC are the five notches on lower pully, are those right? If not, HELP???? secondly, is it possible to set it TDC on the exhaust stroke and not the compression stroke using that. I'm frustrated.

Thanks
 

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I replaced the distributor and can't get it started. the marks I"m using for TDC are the five notches on lower pully, are those right? If not, HELP???? secondly, is it possible to set it TDC on the exhaust stroke and not the compression stroke using that. I'm frustrated.

Thanks
Five notches on lower pulley are correct....you need the left most one for TDC.

First I would double check to make sure everything is connected (especially plug wire orientation). If the timing were that far off, I would wonder if the valves could hit the pistons even just during starting attempts, so if you arent hearing any bad noises Id start with checking connections first.

And yes, my understanding is that it is possible to end up at TDC on exhaust stroke. I actually "rented" a compression tester so I could know for sure when I was on compression stroke of cylinder 1. Since my distributor wasnt removed, I could also tell by the fact that the rotor was pointing at the #1 plug wire. Since your distrib was removed, the compression tester might be the best way.
 

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You could remove #1 spark plug and use a plastic drinking straw to confirm your engine was at TDC for #1 and not a full crankshaft revolution "off" when the pulley marks line up. Do NOT use a pencil to do this !!!

Search Google for more information.
 

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@;
You could remove #1 spark plug and use a plastic drinking straw to confirm your engine was at TDC for #1 and not a full crankshaft revolution "off" when the pulley marks line up. Do NOT use a pencil to do this !!!

Search Google for more information.
I actully have a tube that my dad built for a compression tester that I used to have that I can fit down to the plug hole and be able to feel pressure out the top. It doesn't screw in, but has a rubber cone that will seal the hole, I found that last night, will try today.....

Five notches on lower pulley are correct....you need the left most one for TDC.

First I would double check to make sure everything is connected (especially plug wire orientation). If the timing were that far off, I would wonder if the valves could hit the pistons even just during starting attempts, so if you arent hearing any bad noises Id start with checking connections first.

And yes, my understanding is that it is possible to end up at TDC on exhaust stroke. I actually "rented" a compression tester so I could know for sure when I was on compression stroke of cylinder 1. Since my distributor wasnt removed, I could also tell by the fact that the rotor was pointing at the #1 plug wire. Since your distrib was removed, the compression tester might be the best way.
I"m not hearing bad noises, but it seems to me that the engine timing should prevent valves hitting pistons. That hasn't been changed. Ignition timing, while it can cause problems, isn't going to effect engine timing.
 

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I"m not hearing bad noises, but it seems to me that the engine timing should prevent valves hitting pistons. That hasn't been changed. Ignition timing, while it can cause problems, isn't going to effect engine timing.

Absolutely correct, sorry about that...I was still in the timing belt change mindset (since I FINALLY finished mine last weekend)
 

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Discussion Starter #14 (Edited)
Five notches on lower pulley are correct....you need the left most one for TDC.

First I would double check to make sure everything is connected (especially plug wire orientation). If the timing were that far off, I would wonder if the valves could hit the pistons even just during starting attempts, so if you arent hearing any bad noises Id start with checking connections first.

And yes, my understanding is that it is possible to end up at TDC on exhaust stroke. I actually "rented" a compression tester so I could know for sure when I was on compression stroke of cylinder 1. Since my distributor wasnt removed, I could also tell by the fact that the rotor was pointing at the #1 plug wire. Since your distrib was removed, the compression tester might be the best way.
Is it really possible? I haven't checked mine, put everything back together to their timing marks but havetnt started it up

The engine rotates free by hand

If I check compression for #1 then what is the adjacent cylinder that should be on exhaust? 6? Can't get the tester back there to the other head.

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Is it really possible? I haven't checked mine, put everything back together to their timing marks but havetnt started it up

If I check compression for #1 then what is the adjacent cylinder that should be on exhaust? 6? Can't get the tester back there to the other head.

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Thinking logically, yes its possible. The piston will get to TDC on 2 of the 4 strokes in a cycle: compression and exhaust.

When at TDC of compression, the spark plug needs to fire, which is why the rotor will line up with the #1 cylinder plug wire.

When at TDC of exhaust, the spark plug WONT fire, so the rotor will not be pointing at plug wire #1

If you havent removed your distributor completely, you can tell you're at TDC of compression stroke on cylinder #1 by lining the timing pointer up with the left most notch on the crank pulley and checking to see the rotor is pointed at where the #1 plug wire would be (IIRC its in the 4 or 5PM position if the distrib cap were a clock). I initially didnt even think about the rotor position so I had used the compression tester instead. Rotor position is much easier provided the distrib hasnt been removed/reinstalled.

Im not sure which cylinder would be on exhaust at the point of #1 being at TDC of compression.
 

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Discussion Starter #17 (Edited)

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You already know the answer to that question, which is why it's so important that we help others avoid a similar fate. i turned the engine over and my driver side valves collided with the Pistons. At that point I knew I was 180 degrees off. I paid a mobile mechanic to come out and correct the timing (both valve covers were off). He ended up walking away from the job. He said, and I'm paraphrasing, "most manufacturers have a diagram which shows the correct rocker positions for timing, and I can't find one for your truck anywhere."

I figured the damage had already been done, and I knew I was 180 degrees off (exhaust stroke), so I rotated the L cam clockwise 180 degrees to it's 1:00 mark. Knowing now what I didn't know then the entire process is simple. However, should an individual lose track of how many times the L cam has rotated independent of the crankshaft, to the best of my knowledge this far, you have a 50/50 chance of aligning it correctly. Unless you otherwise locate this mystical Valve position diagram that mechanic was talking about.

The major take away here is this: don't remove your timing belt until you've secured your camshafts. I'm still working on a detailed write up for the procedure, with lots of images, however I need to finish up a couple seal replacement tutorials I'm working on over on TLZone.net first.
 

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When I had mine apart, I moved the Cam enough to get it to spin, on several occasions. BUT the force to move it is so great, all it did was move 90 degrees in whichever direction I was trying to turn it. So it was just a matter of going 90 degrees in the opposite direction to get it back to starting point. I could see how one could lose track of it, though...It scared the hell out of me the first time it happened.

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Discussion Starter #20
You already know the answer to that question, which is why it's so important that we help others avoid a similar fate. i turned the engine over and my driver side valves collided with the Pistons. At that point I knew I was 180 degrees off. I paid a mobile mechanic to come out and correct the timing (both valve covers were off). He ended up walking away from the job. He said, and I'm paraphrasing, "most manufacturers have a diagram which shows the correct rocker positions for timing, and I can't find one for your truck anywhere."

I figured the damage had already been done, and I knew I was 180 degrees off (exhaust stroke), so I rotated the L cam clockwise 180 degrees to it's 1:00 mark. Knowing now what I didn't know then the entire process is simple. However, should an individual lose track of how many times the L cam has rotated independent of the crankshaft, to the best of my knowledge this far, you have a 50/50 chance of aligning it correctly. Unless you otherwise locate this mystical Valve position diagram that mechanic was talking about.

The major take away here is this: don't remove your timing belt until you've secured your camshafts. I'm still working on a detailed write up for the procedure, with lots of images, however I need to finish up a couple seal replacement tutorials I'm working on over on TLZone.net first.
I just figured out that you and everyone else saying this 180 or 360 off thing are all wrong and I made a new thread to explain it

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