20 R - Timing - Which is TDC Compression - Timing Mark At Zero or Between Guidelines

Discussion in 'Engine/Drivetrain' started by Busted Knuckles, Jul 8, 2015.

  1. Busted Knuckles

    Busted Knuckles Member

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    20 R engine : Which is the correct location of the CRANK Pulley timing mark (divit)?

    I asked one technician at a Toyota dealership, and he said the placement of the timing mark is between the two guidemarks just below the number one, like a football being kicked for a field goal between the goal posts for an extra point.

    ( See first set of pics )

    I asked another technician at another Toyota dealership, and this second technician said the timing divit of the CRANK pulley should line up directly under the number zero (0) on the guide.

    ( See second set of pics )

    So which is correct?

    I was also told the numerical guide ( 1-2-8-5 with the guidelines under the number 1 ) are degree marks to be used when setting the distributor with a timing light AFTER the timing has been set, and the engine is running. Correct?

    And finally how can I determine the engine is set to Top Dead Center COMPRESSION (TDCC) or Top Dead Center EXHAUST (TDCE)?

    ( Right now the crank pulley is aligned on the Zero, and the dot on the cam shaft is at 12 o"clock. But when I check the valve clearances on the rocker assembly, everything is way too tight for TDCC. So I'm wondering if the engine is set to TDCE by mistake... or maybe it is TDCC, and the valves need adjusting... )
     

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    Busted Knuckles, Jul 8, 2015
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  3. White Trash

    White Trash Toyotaholic

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    Those numbers are for advance. It is 12 degrees, 8 degrees, 5 degrees and 0 or top dead center on the compression stroke. The second guy is right.
     
    White Trash, Jul 8, 2015
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  4. tyrap26

    tyrap26 Enthusiast

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    tech # 2 is right as white trash said.

    As for finding tdc, you like up crank at 0 and your cam also has a dot on it, should be facing up.. 12 o'clock like you have it set.
    With valve cover up you can also determine tdc by looking at your valve opening.
    Have a look at this, It will make more sense.
    LC ENGINEERING Valve Adjustment Tech
     
    tyrap26, Jul 9, 2015
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  5. Busted Knuckles

    Busted Knuckles Member

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    WT and Tyrp26 and everyone else, thank you!

    You shared your knowledge and insights.
    That teaches me.
    This saves me frustration!

    Thank you.:bow:
     
    Busted Knuckles, Jul 11, 2015
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  6. White Trash

    White Trash Toyotaholic

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    No problem. The 0* mark on the timing printer will coincide with the woodruff key on the crank being at dead 12 o'clock. depending on amount of head and deck milling it's had the cam pin will usually be just to the passenger side of 12 o'clock when at tdc.
     
    White Trash, Jul 11, 2015
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