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Discussion Starter #1
I was trying to adjust the timing on my car and was having trouble getting the timing mark to come around(vaccum advanced unplugged). I could see the mark but it was all the way under the water pump. Next I pulled the cap and found what looked to me as the rotor being off at least one tooth. I didnt even know it would run like that. So I have run new wires and installed new plugs and set the timing to point @ number one. No start just a few puffs. Turn the dist both directions and finally get it to start but wont run for crap. No misses just no throddle response and wont idle. Is it possible it will run at 180 out of timing? Other wise do you think it is possible that the problem mgith be bigger than that. The guy before me seemed to be a real peice of work:mad:. Just trying to figure out why it looked as if it was of a tooth but ran ok and now wont run at all.

This pic was a TDC and balancer on zero

 

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Could have a 305 balancer with ther timing location straight up behind water pump.

Need to verify TDC mark on balancer is TDC at piston.FIRST

No engine will not run 180° out.
 

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Discussion Starter #3
I guess that would not be to much of a surprise considering the other things I have found:no:. What would be the for sure way for total TDC? Remove valve cover and watch valves or just wait for it to stop pushing air out with finger over spark plug hole? Maybe someone has a pic of a 305 and 350 balancer to show the location of the mark to the key way???
 

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Get an adjustable 'Piston Stop' from an auto parts store or IE: Summit. Take out all the spark plugs, and screw the piston stop into the #1 cylinder. Slowly rotate the engine with a breaker bar until you feel it touch the piston stop. Mark the balancer with a sharpie or something that you can see but comes off later. Then rotate counterclockwise until you feel it hit again. Mark another mark. The middle point between the 2 marks is TDC, or close enough to figure out what your timing mark is already set at - right on or 10advanced or whatever. Use some brush-on paint or some sort of sticker to mark TDC, and you're good to go.

THe piston stops are like $15-20. With the adjustable one, if you never feel the piston touch it, screw it in more and try again.

If you try to do this without removing all the plugs, you will bend the piston stop, because the motor will be hard to turn and you won't feel it correctly.

Be gentle and patient and it is easy.
 

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You could basicly use the wrong balancer and install you own timing marks on it?
Yep. :yes: Unless it is a 400 SBC with the external counterweight. Then you'll have BIG problems.

I fell victim to the problem of a 305 balancer on a 350. Couldn't figure out WTF the timing was way off. Found TDC the way Al described (half way between the two stopping points using a piston stop tool).

One thing I will contribute is that it is hard as hell to see a Sharpie mark on a balancer with your timing light (grease, dirt, etc). Clean the balancer and use some White-Out (Liquid Paper) that has the brush in the cap to mark your TDC for timing the engine.

Timing tape is also another very nice tool to fine-tune the engine once you have it running OK. Cheap! $6!
 

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Big Al is right. If you want to do it on the cheap, get a CLEAN shop rag ( i use the blue ones from parts store ) and JUST stuff it tightly in the #1 cylinder spark plug hole ( plug removed of course ). And slowly crank the engine, until it POPS out. The pop is pretty loud, so you will definately hear it. This will ensure you are on the compression stroke for #1. Same as Big Als finger check. Once it pops out, rotate the crank with and follow the same instructions.

My balancer and timing tab were right on. The rotor was pointing at the #1 tower on the distributor.

GL

Gary
 

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If you use timing tape, my experience with it is that no matter how clean I make the balancer it ends up flying off at some point. After you put it on, spray with a can of clear coat.
 

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Assuring your balancer is correct

Is step one, as described

There are 2 terms used for TDC

There is top center, which means the piston has reached its uppermost travel

There is top dead center, which means that the piston, rod, and crankpin are all in a straight line.

You have a certian amount of degrees at top center, where you can move the crank,and it will not affect the position of the piston

They make a screw in Dial indicatior where you can determine TDC
SO you bring it up on compression stroke, youll see the indicator hit top center, you record the reading, and slowly turn the crank until it starts to decline, spiit the difference, and thats your absolute Top dead center.

In Aviation doing a differential compression check, we pressurize the cylinder with 80 PSI, and when your at Top center, if you let go of the prop, your gonna get a bruised head, or worse, so you slowly move the prop, until it " sticks " this is Top Dead Center.

Other more basic ways to do this, such as use a piece of flexible hose, to feel the piston travel, and if its at the top of the compression stroke , you should see your timing mark clearly, if you dont, your balancer may have spun, or you have the wrong one, thats the first thing I would change.

Steve
 

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If you pull the valve covers and split the overlap on #1 or #6 will get your TDC. If you split #6 #1 is TDC if you split #1 then #6 is TDC (#1 and #6 are 180 out from each other)
To split the overlap turn the engine over in the normal direction and watch the exhaust valve on the cyl your working with and when it almost closes the intake will start to open, when both valves are open the same amount then you are at TDC on the oppsite cyl.

This wont cost you anything except if your valve cover gaskets are stuck to the head.

Mitch
 

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If that's the original balancer, Did you replace your timing cover with a chrome one?
Late seventies 350 and 305' had the 12 o'clock timing tab. Take a look at the old timing cover. It's at 12 o'clock under the water pump.
You'll need to mark your balancer with a new timing line.
 

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If you pull the valve covers and split the overlap on #1 or #6 will get your TDC. If you split #6 #1 is TDC if you split #1 then #6 is TDC (#1 and #6 are 180 out from each other)
To split the overlap turn the engine over in the normal direction and watch the exhaust valve on the cyl your working with and when it almost closes the intake will start to open, when both valves are open the same amount then you are at TDC on the oppsite cyl.

This wont cost you anything except if your valve cover gaskets are stuck to the head.

Mitch

That method is understandable but is only as accurate as the cam grinding and timing gear assembly and doesn't pinpoint when the piston is at TDC. A piston stop is the easiest way that's accurate.
 

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Discussion Starter #15
Wow some of those explinations are quite difficult to understand. I have never had a problem before when setting timing. I was wonder is it possible the cars cam was one tooth off from the crank or would that cause hardpart failure. The block is a 350 #3932886 and heads #3932441. I have changed nothing on the engine besides the carb I just built. Then I started having problems with the carb and though the timing might be the issue. I put the timing light on it and the mark was way under the water pump. So I pulled the cap at what I believe was TDC and found the rotor off. In the pic the engine is what I though TDC and crank shaft on zero.
 

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Forget about the rotor location..it don't matter. You need to find TDC and make sure it really is TDC on the balancer. Then the distributor in. The standard is to the rotor pointing to the number one cylinder, but it don't matter. Just as long as all your plug wires line up it doesn't matter where the rotor is pointing. If it were pointed to lets say #8 cylinder when at tdc..you would just put #1 plug there and cont. around. And if all you did was change carbs then you have a carb issue not a timing issue, but i would set the timing right and then do the carb. Youve got a huge vaccum leak or something if the timing seems way off to make it run. Remember more advancing leans a motor out, more retarding fattens the motor.
 

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Discussion Starter #17
Pulled my balancer today and found that the timing mark is about 2 1/2" left of the keyway. From the balancers I have found online the timing mark seems to be only about 1/2" left of the keyway. I am looking to get some tips from you guys to hoefully solve my timing issues. I want to replace the balancer because it has a stripped bolt hole anyways. The casting # on the block is 3932386. Thxs for any help
 

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There are three timing mark locations used over the years on Gen 1 engines. It doesn't matter which one you use, provided you use the correct timing pointer that matches the mark on the balancer. That's why you should always verify #1 piston TDC and the "0" timing mark coincide.

Balancer outer rings can and will slip so it should always be checked when rebuilding and engine.

Once you have that OK, then you can install and index the distributor relative to #1 TDC compression. You'll be ahead of the game if you drop it in at base timing rather than TDC. Rotate the balancer back 10 degrees (or whatever your base timing is) before TDC and then put the distributor in.

The rotor should point to the #1 terminal on the cap. The body needs to be installed so the vacuum canister has enough room so you can rotate the distributor without hitting anything. Generally the vacuum advance nipple wants to be about 7-8 o'clock when viewed from the top.

The distributor rotor will rotate slightly while installing the distributor because the gears are helical so the shaft turns as it drops down. It's kind of tricky to get the rotor close to the terminal because the cap will off. If you mark a vertical line with a Sharpie on the distributor body indicating the #1 terminal centerline before removing the cap, it will be easier.

You may also have to align the oil pump drive shaft so it mates with the drive tang in the end of the distributor. Use a long screw driver and a flashlight. It may take some "spacial skills" to visualize the orientation of the distributor tang.

This is all odd since you said the only thing you did was mess with the carburator, and you had no trouble timing before but now the mark is appearing under the water pump. If this engine had the right balancer and timing pointer in the first place something else is wrong.

Did you have the inductive pickup on the #2 plug wire (pass side front) instead of the #1 (drivers side front)? Did you pull and plug the vacuum hose to the vacuum advance?
 

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Discussion Starter #19
Never checked timing on the car! Since I have taken ownership of the car the carb was junk. So I rebuilt the car and had it running on stands. Then took for a test drive and had ok performance. So this lead me to checking the timing and could not get a mark to come up to the indicator that is on the engine now. Once pulling the dist cap it looked as if it was 1 tooth off. I then changed all plugs and wires and reinstalled the dist at what I though was TDC and pointing at # 1(balancer was on zero at this point too). Not it barely runs a all. So back to the drawing board. It sounds as if I need to get a balancer and a indicator that co-insides with the balancer. The old balancer is 8" in dia and several peole have 6 or 6 3/4. What whould the difference be? here a pic of my balancer

 

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What's the timing cover and tab look like? Post pic.
 
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