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how to set timing????

25K views 24 replies 9 participants last post by  sixsix 
#1 ·
OK last thing I think I need to do to my van is set the timing again, I want to start from square one and pull the dizzy and set #1 tdc can some one tell me step by step the correct process for this?? I wish to do this as my distributor is currently in the wrong position relative to the motor and by this I mean the distributor body is turned to far clockwise I believe because the two wiring plugs that go to it are pointed at 8 o'clock when I think they are supposed to be at 7 o'clock I got the rotor pretty close to where it was when I pulled it but I just want to get it right so I can just drive the dang van without having to stomp on it to have it run smooth, PLEASE HELP
 
#2 ·
Astro 355 showed me how to find TDC a while back , this is from a old post

webcat wrote:
Whats the easiest way to get your #1 piston at TDC and have it be on the compression stroke?
Astro355 wrote answer
Take the valve cover off on the driver side. While rotating the engine by hand, watch the valves. During the exhaust stroke, you will see the exhaust valve open. Right before the compression stroke, the intake valve will open and close and during compression, both valves will be closed.
 
#3 ·
kinda helps but I am not to excited to take the valve cover off, is there any way to use the timing mark on the crank pulley?? I have heard that if you pull the number one plug you can put a small rag or similar item in the hole and the compression will blow it out when #1 is on its comp stroke?? then just line up the timing mark on the pulley with the pointer ?????
 
#4 ·
I pull the #1 plug, stuff a rag in the hole good and tight with a screw driver. Bump the motor until you hear it "POP" out, then disconnect the batt. and use a wire as a feller through the spark plug hole and crank the motor back and forth by hand to get the piston at TDC.
 
#6 ·
Gotta get the rotor pointing towards the #1 spark plug on the dizzy cap once you got the #1 cylinder at TDC.....right?

I have never had to do TDC......I always marked the dizzy and pulled it out and it always dropped right back in for me.

 
#7 ·
Why not just loosen the distributor and rotate it from the 8 o'clock position to the 7 o'clock position? You don't need to take it apart to do that. And for that matter, why not just start the van, loosen the distributor and slowly rotate the distributor until the van idles good. That's how I time my van. That's one reason why I love these vans. I can rotate the distributor while driving it down the road. Makes it real easy to power time it.
 
#8 ·
astro355 said:
Why not just loosen the distributor and rotate it from the 8 o'clock position to the 7 o'clock position? You don't need to take it apart to do that. And for that matter, why not just start the van, loosen the distributor and slowly rotate the distributor until the van idles good. That's how I time my van. That's one reason why I love these vans. I can rotate the distributor while driving it down the road. Makes it real easy to power time it.
355 FTW!!!!! :rockon:
 
#9 ·
Thats the thing here if I were to rotate it back to the seven oclock position then effectively my timing would be thrown off because when I reinstalled the dist. I lined the rotor back up as close as i could mith the mark i made where the rotor was pointing when I removed it does that make sense??
 
#10 ·
1992RS said:
Thats the thing here if I were to rotate it back to the seven oclock position then effectively my timing would be thrown off because when I reinstalled the dist. I lined the rotor back up as close as i could mith the mark i made where the rotor was pointing when I removed it does that make sense??
You are over-complicating this. All you have to do is remove the doghouse, start the engine, loosen the holddown just enough so you can rotate the distributor and slowly turn the distributor and listen to the engine. Turn the distributor both clockwise and counterclockwise, not a lot either. Only a few degrees can make all of the difference. Mark the starting position if you like. Do this while in idle and even driving down the street. Now, when doing this while driving, adjust the distributor ONLY when stopped (at a light, stopsign, whatever) and then drive it. Try to notice things like torque and horsepower and adjust it to the point where both "feel" the best.

You have to understand that every engine is different be it by size, displacement, wear and age. Sure, there are general guidelines to setting the timing on an engine but if an engine wants more timing, give it more timing (or vice versa regarding retarding).

If you want to wait til this weekend, I'll shoot a video of this while I'm doing it in my van.

And did you know that running too far advanced can make your engine run very hot?
 
#11 ·
No I didnt know that, my only real issue with just adjusting it where its at is that the wires that plug in to the dizzy are drawn pretty tight due to its position so I would be unable to turn it clockwise only counter clockwise thats my issue, I would post a pick if my fiance didnt take my camera with her to her sis' graduation.
 
#12 ·
Oh ya a tech video coming I can't wait! :rockon:

Here is the dizzy placement on my '92 W motor.......just to give you a idea of where mine is...if its any help to you. :shrug:
 
#15 ·
1992RS said:
Yeah mine is like 20-30 degrees clockwise from where yours is and thats why my wires are so tight now I know I need to pull it out and try moving it back some.
Oh, now I see. If that's the case, you will have to remove and reinstall the distributor. The last thing you want to happen is short those wires out on the distributor housing since they are too tight. And yes, that can happen.
 
#16 ·
Yes that is my fear, I plan on doing it tomorrow by first clocking the motor and then pulling the cap after that I will pull the dizzy and clock that to the correct position and put it back in and hope she purrs like like a kitten after some slight tweaking
 
#17 ·
Here's what I've always done:
  • Remove all plugs[/*]
  • Insert a straw into Plug # 1 hole[/*]
  • Put your finger into Plug #1 hole[/*]
  • Manually rotate engine to feel compression build up[/*]
  • Insert straw into #1 plug hole[/*]
  • Continue rotation of engine[/*]
  • Watch for the straw to go up to it's highest point[/*]
  • At the highest point of the straw's rise, that's TDC, stop rotation[/*]
  • Ground the #1 Plug so you can see the electrode[/*]
  • Unlock the distributor so you can manually rotate it[/*]
  • Turn the ignition to "Run" mode, not "Start" mode.[/*]
  • Manually rotate the distributor so you see a spark on the grounded plug[/*]
  • Tighten the distributor down when you just see the spark occur.[/*]
  • You're done[/*]
I've used this method on EFI (using TDC as a spark point) engines, and on non EFI (using 6-7 degrees BTDC) for years. It's worked, and I rarely use any timing light. This sets the sparking at the gnat's eyebrow, not in the ballpark. If there's a continued problem it's now in the distributor gearing or timing chain that drives the gearing.
 
#18 ·
You don't need to set the timing by finding TDC for cylinder #1. All you need to do is much the rotor counterclockwise. Mark the distributor alignment first. Remove the distributor and once you feel the distributor shaft gear become free of the camshaft drive gear, rotate the rotor counterclockwise just one tooth and reinstall the distributor. It may not go in all the way, but the slot on the oil drive shaft is oversized so you should be able to work it in. You will then rotate the distributor housing the same distance as the rotor rotated. Start the engine and time if necessary. If you still need to move the distributor, redo the steps again.
 
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#20 ·
sixsix said: "13 years - HAS to be some sorta' record, right ? " ... not so sure...this time the poster says to use a 'long flat head to turn the water pump..."! That is a first for me. o_O
I would really like to see how that is done. :oops:
Just joking , of course, but I still had to read it twice before realizing what I missed.
Rod J
Issaquah, WA
 
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