340 engine timing issue

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dust-u

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i am helping a friend get his challenger out of hibernation..it runs a little rough so i suggested we check the timing..when i put a light on it i cannot locate the timing marks no matter how far we swung the dist?we did remove the dist drive gear to prime the motor..it has a stock cam and new chain..and the motor is fairly fresh.it always ran well from what he says.is it possible when he reinstalled the drive gear he is off somehow? suggestions?:read2:
 
did you remove the vacuum hose from the dist and plug the end before you checked timing? Can you see the timing light flash so you know its working? Did you use the front plug wire on the driver's side? If its running it can't be too far off. Must be something simple.
 
yes to all those questions..it is running well but it is timed by ear..personally i would like to know the timing is exact...keep those suggestions coming...
 
Not to be a jerk....but did you mark the line on the crank pulley with a crayon or something..that mark is hard to see on the crankwhen running....you can't see that mark at all on the crank no matter howfar you turn the dist in both directions???....This is a small block v-8 correct....take # 1 spark plug out, driver side front and turn engine over by hand w/ at 1 1/4 socket, put your fingure over hole until you hear air trying to push your fingure out...that is coming up on TDC top dead center compression...put and long screw driver in the hole and slowly turn engine over by hand until the screw driver stops coming up...that is tdc...remove dist cap..should be pointing at #1 spark plug wire on dist cap....if so good....It sounds like to me it will not be pointing their and you may have to remove dist and take a long straight screw driver and turn that gear down in the dist hole..do not lose the oil pump shaft down the hole it will pizz you off.... so it lines up with dist shaft facing #1.....if all is good their install dist it should be close to # 1 cylinder.....vacuum pull should be parallel to windshield....recheck timing you should be able to see line now....Let me know if tis works or if you can;t understand what i am saying.....call me 607-647-9547....oh yea firing order is 1-8-4-3-6-5-7-2
 
outer ring on the balancer could have spun...

move engine to number 1 tdc and see where the mark is on the balancer...
 
Has the damper or front cover been changed? '69 and older has a passenger side timing indicator mark, while 70 & up use the driver side for the marks.
 
Well, if it's running it can't be that far off. You sure you are on the #1 plug wire?
 
i believe the motor is the original to the car..i will go back and check to see how the dist lines-up.
 
Has the damper or front cover been changed? '69 and older has a passenger side timing indicator mark, while 70 & up use the driver side for the marks.

Like he said see what side the bottom hose is on it might have the wrong water pump on it.
 
i have noticed that the curb idle screw is backed off as well.to the point that it does not make contact..should i suspect an intake, carb vacuum leak?
 
We need to know what side the lower rad hose is on first, so we can determine what side the timing marks are on.....don;t get a head of your self because you will make more problems.....did you do what i said in my first posting and what these other guys are telling you?????.....plus you have to remember you messed w/ dist, the timing is off.....I guarantee it....and sure you may have a carb issue if it wans't tuned after install....and you are looking for a vaccuum leak because...it runs rough..could be, but lets find some timing marks and get it close to where it should be...then if it still has a rough idle, procede from their....you don;t want to drive it w/ timing out of wack you will burn a piston, because it is tough to hear a spark knock when you are driving it.......tell me if I am wrong guys...but i have tuned a bunch of these small blocks from 70 and up.....keep us posted.....stay calm it will come to ya...
 
First step, pull the #1 plug, and turn the engine by hand while you hold a finger over the plug hole. When you feel pressure on your finger, you are coming up to TDC on the compression stroke. Find the timing scale on the timing cover, and watch as the timing mark on the balancer comes around to reach "0". When they line up, take some brake cleaner and blow out the groove and the cover. I use white-out correction fluid to mark the slot to see it better. I agree, you have a timing issue. And you will have to tune the settings of the carb once the timing is set properly. I would start at 10° initial, then see what the carb is doing. You may not be on the idle speed screw if the choke is still "on". Let it warm up and see what she's doing.
 
ok...i will post progress.later in the week...wife has to have some surgery and the car will have to wait for me to get back to it...
 
the waterpump has the outlet on the drivers side...
 
With the outlet on the drivers side, I believe that is a 69 and older style water pump. Where is the timing indicator on the front cover? Is it on the drivers or passenger side?
 
the waterpump has the outlet on the drivers side...
You mean the inlet is on the drivers side? If so it is a 69 down and the timing marks should be on the opposite side or the pass side. The 70 & up were just the opposite.
 
hey..i was wrong...it has the aluminum waterpump and its inlet? is on the pass. side...the timing marks are on the drivers side..I need to take a break for a couple of days guys personal stuff...can i count on your help with this after that time? or do I need to repost? I will have the car brought here so we can try to do things in "real time" please dont give up on me i want to have this thing running like a swiss watch...I have some compition I need to "beat down"... Jim
 
What you need to do even before you try to start the car is check to make sure the outer ring on the balancer is'nt spun.Take out #1 spark plug.ONLY by hand turn the engine to TDC by the piston forget the timing marks on the balancer for now.It doesn't matter whether or not comp or exh stroke the piston sees TDC twice( use a really soft metal or wood dowel.)once you get the piston to TDC as close as you can. then look at the balancer timing mark.If it's close,cool if not the balancer is bad .Replace it
 
How long has the gas sat in the tank prior to use? Gas over 90 days old that has not been treated with something like sty-bil will break down and not burn well.
 
wife has had her surgery.....she is now recovering..I will post in a couple days the results of all questions asked..and ask some more...thanx for looking in...
 
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