engine running funny

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rich weyand

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From what I can tell looking around, the 1985 305 had the timing tab at the 12:00 position, which would make your actual timing 33* less advanced than what you are reading at the 2:00 position. So you may not be 22* before TDC; you may be 11* AFTER TDC.

This should be easy to see. Turn the crank so the keyway on the crankshaft pulley (as viewed from the front) is at 45* clockwise from straight up. On a map this would be northeast. On a clock it would be halfway between the one and the two. You should be able to do this with an inspection mirror, I think.

Now, where is the timing mark on the wheel? Is it straight up? Or is it more pointing with the keyway?

Another way to do this is to turn the engine until the keyway is straight up. That might be easier to see, especially from underneath. Is the timing mark also near the top of the timing wheel, or is it off to the left, like northwest on the compass or between the 10 and 11 on a clock face?

You can also remove the #1 spark plug and just get kinda close to TDC. Just keep moving the engine around by hand and feeling for the piston with a long rod. Keep moving it until it takes the least rod to hit the piston. For this gross of a determination close is good enough. Where is the timing mark on the wheel?
 
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Mmoore031908

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Ok I will check tdc probably tomorrow due to weather today. The original 305 tab and balancer point at 12 but the new ones that I got are both around the 2 o clock position. I will try and get a picture to show you my setup.
 

rich weyand

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The balancer isn't at the 2 o'clock position: it goes round and round. What makes you think it is marked for the 2:00 position?

Does your block have the mounting holes for the tab in both positions?
 

rich weyand

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FWIW, the pic for the balancer you bought shows one that is clocked for the 2:00 position.

It may be a picture they use for all the models, though.

I am trying to find out.
 

rich weyand

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Yeah, it's almost certainly a 10* balancer, so that isn't it.

I can't for the life of me figure out why your engine sounds like it is running retarded, given the timing numbers you are seeing.

Let me ask a stupid question. I don't want to insult your intelligence, but it has come up before. What spark plug wire are you clipping the timing light on? Don't just say #1; which position on the engine?
 

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When I rebuilt my 350 and ordered a new harmonic balancer for it I had to get a bolt on timing tab as the timing cover wouldn't work for the balancer I had.

People do odd things to trucks without thinking about the other details.
 

Mmoore031908

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I understand. I'm open to any suggestions. When I clip it to the number one spark plug I try to clip it as close to the plug as I can.
That's why I bought the extra balancer and tab because I had originally bought the tab but the old balancer wouldn't work with the new tab.
 

rich weyand

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OK, so like I said, don't just say number 1. Which cylinder do you call number 1? Front, back, passenger side, driver side. Stupid question, I know, but like I say, it's happened.

Second, have you had a chance to verify that that is a 10 degree wheel? You should be able to tell pretty easy, as above. Here's an even easier way. Crank the engine around until you can see the "0" timing mark near the 2:00 tab. Put a piece of tape hanging off the front of the timing wheel where the "0" is. Now rotate the engine anywhere you need to to be able to see the keyway in the front of the wheel, whether with an inspection mirror, or from underneath, or by taking the fan shroud bolts off the top and pushing the shroud back, whatever. You need to see the keyway. You won't be able to see the timing marks at the same time, but you should be able to see the tape and the keyway at the same time. Is the keyway more or less lined up with the tape, just a little clockwise from the tape? Or is it like an eighth of a rotation clockwise from the tape?
 

Mmoore031908

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10* wheel?? If you are looking at the front of the engine with the hood raised it is the cylinder closest to the front of the engine on the drivers side.
 

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10* wheel?? If you are looking at the front of the engine with the hood raised it is the cylinder closest to the front of the engine on the drivers side.

People like Rich take peoples knowledge for granted.. This explains it :)

You must be registered for see images
 

rich weyand

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10* wheel?? If you are looking at the front of the engine with the hood raised it is the cylinder closest to the front of the engine on the drivers side.

OK, just checking.

10* (10 degrees) wheel is a balancer for the 2:00 position. There is also a 2* wheel (2:30) and a 40* wheel (12:00). The angle is the angle of the "0" timing mark counterclockwise from the keyway.
 

rich weyand

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People like Rich take peoples knowledge for granted.. This explains it :)

You must be registered for see images

Actually, I thought I explained the three balancer wheels earlier in the thread....

Probably doesn't matter. It's almost certainly a 10* wheel.

Still scratching my head on this one, though.

Hey, if you are using a fancy adjustable timing light, make sure it's set to zero offset when you measure against the timing wheel marks.
 

Mmoore031908

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ok you did explain that earlier when you mentioned it like that had no clue. I have a regular timing light you just hook it up press a button and it flashes while the buttons pressed no fancy dials here. I should have a chance to confirm tdc and which balancer I am using. It is nice and sunny today just a little cold.
 

Mmoore031908

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So I found tdc and it appears that my tdc is about 3* btdc but wouldnt that make my true degree reading 25*?
 

Mmoore031908

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I do also have the 10* balancer. Seeing that I am probably going to tear it down and start from scratch this weekend.
 

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