piston possition for TDC

[Jeanda]

-"Would setting your piston #1 "before or after" it's actual TDC be called "advancing or retarding"-the timing?"

[Pewter2K1]

I dont know if you can do it that way, but the way to do it is to set it at TDC. then move the cam using a degree wheel to achieve an advance or retard in the timing

[AZ3.8Camaro]

With regard to cam install or what?

[Jeanda]

the reason why i ask is cause im in the middle of replacing the valve seals & just had the heads resurfaced. i started to vaccum & clean debre from the cylinders and began to hand-crank piston #1 to TDC. right then i noticed the TDC notch on the balancer had passed 12o'clock and was sitting at 1 o'clock.
is this normal?
could it explain why the idling was lopy and "cam"-like at startup?

[ September 28, 2005, 04:31 PM: Message edited by: Jeanda ]

[AZ3.8Camaro]

The crank of the pulley would have to physically twist in order to cause this kind of a problem.
That would be VERY unlikely.
It is hard to tell where top dead center is by using just your eyes. I would trust the crank mark, more than myself looking at the piston movement.

[Jeanda]

so even with the heads physically off of the motor and i can visually confirm it and swear to it on my very exsistance, that as the crank is on the 12 o'clock setting...the #1 piston is less than an inch away from it's highest point of its stroke.
knowing that it's not, i'm supposed to believe that it IS at it's highest point?
i'm sorry, and i don't want to sound like a computerized-robot...but,
"can you explain why this is because that statement does not compute"

[AZ3.8Camaro]

I am saying that the mark on the crank pulley, if installed correctly, is a factory marker as to where the engine should be when you install the cam chain, etc. How could that be wrong?
A)Crank is twisted.
B)Pulley is twisted.
c)Pulley is on wrong or wrong pulley.

Here's what I would do:
There should be a mark on the crank itself. I would take the balancer pulley off and look at that.

[Jeanda]

ok, i'll check the marks alignment with the mark on the crank itself.
...a year-or-so ago i took the car to get worked on at this auto shop. i'm trying to find out if it was put together correctly. maybe they made adjustments or thats the way its setup from the factory~i don't know~. i'm wondering if its normal or if it can be adjusted or any info on it?
...also, if it is normal-is it set that way so by the fraction of a second it takes for the signal to be sent and the spark to fire, the piston will have moved that much more to achieve maximum compression?

[Jeanda]

anyone??

[98Camaro3.8]

Originally posted by Jeanda:
i'm wondering if its normal or if it can be adjusted or any info on it?
...also, if it is normal-is it set that way so by the fraction of a second it takes for the signal to be sent and the spark to fire, the piston will have moved that much more to achieve maximum compression?

Think he said it twice that the only way it could do it is if something is either bent or installed wrong. ;)

Pulling off the front cover will tell you if it's really lined up or not.

[viper98885]

There is a timing mark on the balancer on the 3.4L V6. You want to line it up with the bolt head that holds the crank position sensor to the engine for TDC. That is at about the 1 o'clock position.

[Jeanda]

So the balancer mark and the mark on the crank-shaft gear does'nt need to match? That would explain the 1 o'clock setting on the balancer as the crank gear mark lines up @ 12 o'clock?
...i don't know if that made sense so--
-crank shaft GEAR...12 o'clock
-balancer... 1 o'ckock
-cam GEAR... 6 o'clock
-crank shaft sensor.1 o'clock
...correct if i'm wrong

[ezrollin]

why is fullTHROttle a scam?

[Jeanda]

[img]graemlins/rofl.gif[/img]

[WickEdSix9838]

I wouldnt worry about it because if the timing chain was off a tooth, the car would either not run or run so bad you'd know something was wrong.