HELP! My truck won’t start!

Robert Bare said:

It doesn't matter where the dizzy is inserted, as long as the rotor is pointed at the wire going to #1, as said.
I don't think you "get it". Now the way a Chevy 350 works, #1 and #6 are "companion cylinders". This means that they, and only they, will be at TDC when the crank timing marks are lined up, be it compression/fire, or exhaust. No other cylinders have this ability with the timing marks. So, if you are timing it on #6, is just fine.
If you are limiting it on #4, as you say, then you don't know where #4 is, or your balancer has slipped on the rubber. When setting timing on old,dirty, rusty engines I have used the coil wire for the inductive pickup on a timing light, for the extra flashes and light. But it is hard on timing light bulbs.

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Truck82 said:

That’s also another “weird” thing that’s going on. I knew the no. 6 was the companion with no. 1 but it just runs like a top when timed with no. 4 so I go with that one. I’ve had that bad feeling in the back of my mind about the balancer being slipped. Is this an easy fix?

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Robert Bare said:

OK, first, be aware some years had a small tube welded on the timing cover.The reason is, at the factory, and dealers, a probe was uses to check the timing. These had 2 timing marks on the balancer. A thin groove one, for using a timing light, and one further away, much wider, for using the probe. So make sure to use the right one.
Now, if you suspect balancer has "spun", you need to put #1 or 6 on TDC. Most of you probably don't have a TDC finder, as it isn't used much so older mechanics, engine builders and small engine builders are about the only ones that would. Don't fret, you don't need to be precise. You do need another person. Use a wire down a plug hole, copper is safe, as you are inexperienced, I mostly used a thin long screw driver, over the years. You have to judge when the piston stops coming up. That actually is not TDC, as it needs to go a bit further, for the connecting rod to go "over center". If the timing marks are way off, it is bad. If off maybe a little- inch or so, you can get closer by going one way, when you think it has stopped coming up, stop and put a crayon mark on the balancer. Then go past(remove wire/tool), then do it again, going backwards, then put another crayon mark on the balancer, the middle of the 2 is close to actual TDC. If the timing marks are off, then it is bad. The repair, simply replace the balancer. BUT, while you have your fresh crayon marks, you can quickly set the timing with a light.
BTY, never had crayons in any shop, we used tire crayon markers,lol!
While down there, you also can rock the balancer back and forth, and see how much slop is in the chain/gears. Now it may seem like a lot, so judge it by the marks and the timing scale. Don't be surprised to see 10 to 20 degrees of slop, normal for these "old style" engines. 10 degrees will feel like a whole lot, so people easily get worried, for no reason. Once you get above/past 20, might be time to consider replacement.
A friend and a long breaker bar, and a socket extension can make these tests happen in just a few minutes.

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legopnuematic said:

You had mentioned the block is a 1970 block in another thread?

Where is your timing pointer? A 1982 should have the timing pointer at 12:00 behind the water pump, a 1970 should have the pointer at ~2:00. The balancers are different between the two, where the timing mark is located in relation to the crank key.

Just something to consider and verify. It’s been seen before mixing those parts and producing odd results when trying to properly set time.

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