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Thread: Johnson "70mod"

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  1. #18
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    Nov 2016
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    just because your English dont come across good, do not think I am an should try to explain a bit more what your problem is.

    you say the thermostat hole ? wtf is that supposed to mean ? why are you worried about thermostat when you only use a butchered one anyway ?
    do you mean thermostat will not fit now ?
    or do you mean the recess has been shaved away letting the thermostat fall though ?
    or do you mean the thermostat itself has a hole in it ?

    As said I would do earlier I Just measured Original 56 later style cylinder head part number 339221 the pocket depth is 0.5315 (13.5mm) and the volume of the chamber is 32.1cc.
    CC was measured with the plug hole taped over and filled to be exactly level with top of the head surface inc the chamfer.
    this is standard from factory never been touched since it was new.
    also measured across the chamber and it is 54 mm at bottom of chamfer ( 2.12598 inches ) and 58mm at the top of chamfer ( 2.2834 inches ).
    chamfer is 4mm deep (0.1574 inches).

    used medical syringe to find the volume and used accurate and calibrated Steel Vernier Caliper and then checked with cheap digital vernier gauge.
    amazingly the cheap digital was giving exactly the same dimensions..

    " You should open once one of these engines and have the parts on Your hands to look at them properly. Then You understand."

    As for me taking one of these engines apart and looking into the internals, I only got down this far on the top bit..
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