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BT7 Timing mark and pointer question

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dvu101

Jedi Hopeful
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Is the timing mark and the pointer indicating TDC?

If so, how far in front is 15 degrees before TDC?

I had my distributer rebuilt and now it runs GREAT from 2500 rpm up.

From 800 to 2500 rpm its slow, not missing, just slow.

I replaced all the normal tune up parts, rebuilt the vacume advance etc...

I have a Bentley manual and its not clear to me.

Thanks Scott
 
Assuming you have points vs electronic, the pointer is stationery and the mark on the timing pulley indicates how far from TDC you are. The distance is about 1/2-3/4 inch below the pointer. Advancing the timing brings the mark on the timing pulley closer to TDC, and retarding the timer drops it lower.

I'm really not sure of the distance but memory tells me it's about .575 inch from TDC should be about 10-15 degrees. That is if you can get the idle down to 600 rpm.

The AHCUSA has a great website that you can go to for specifics.

Hope this helps.
 
Johnny said:
Assuming you have points vs electronic, the pointer is stationery and the mark on the timing pulley indicates how far from TDC you are. The distance is about 1/2-3/4 inch below the pointer. Advancing the timing brings the mark on the timing pulley closer to TDC, and retarding the timer drops it lower.

I'm really not sure of the distance but memory tells me it's about .575 inch from TDC should be about 10-15 degrees. That is if you can get the idle down to 600 rpm.

The AHCUSA has a great website that you can go to for specifics.

Hope this helps.
Click to expand...
My records show that 1/2" is for 10 degrees and 3/4" is for 15 degrees. Just try and hold your ruler steady while adjusting the timing! lol
Patrick
 
Maybe I'm not fully understanding...but wouldn't advancing the timing bring the mark further from the the timing pulley pointer (TDC)...meaning the engine is firing before it reaches TDC? By further I mean upstream of the pointer...
 
First, I'd invest in an timing light that advances. Life is easier if you can just dial it in. Put the dial at 15 degrees and rotate the dizzy 'till the pointer and the notch line up. Otherwise, the notch on the pulley should be on the out-board direction from center of the engine. If you measure with a tape measure you can paint (white) a spot on the pulley that you would line up with the pointer.
 
Thanks All..... That was what I need.
 
Nevets is right, advancing the timing puts the line on the damper further away (before) from the pointer (when the timing light shines it's blink). Retarding moves the line on the damper closer toward the pointer.
 
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