Engine & Gearbox Timing a belt driven SOHC?

Discussion in '6th Generation (1997-2002)' started by AndyB1976, Thursday 13th Mar, 2014.

  1. AndyB1976 Valued Contributor ★ ★ ★ ★ ☆

    United Kingdom Andy Aberfoyle
    Hi guys

    This is a spin off thread from my Spark Plug fouled thread which covered various issues which I am still dealing with. Therefore I will keep this thread to the specifics and tolerances with regards to setting the timing belt on my f18b2 SOHC.

    I will quote my last post in my previous thread for reference

    My last point was to retract the ability to prove timing out with a cylinder leakage test so paragraph (4) I won't use as an example because I can't prove it. With the cam lobe still on the base circle with the crank as little as 1 tooth out then the chamber will still be sealed

    Timing Marks

    Cylinder1_tn1. Cylinder1TDC_tn1. Cylinder1TDCtimingMark_tn1.
    Last edited: Thursday 13th Mar, 2014
  2. Ichiban Founder Staff Team

    England CJ Leeds
    I would say its every slightly open.. but need a second pair of eyes to look at it..

    @Beefy, @SpeedyGee and @PeteMM chaps what say you.
  3. AndyB1976 Valued Contributor ★ ★ ★ ★ ☆

    United Kingdom Andy Aberfoyle
    My reason for that assumption was that during the end of compression stroke, the spark fires at 12° BTDC and the piston is still travelling up towards TDC.

    Therefore I am thinking that if a valve begins to open as soon as that one or two teeth on the crank has rotated past TDC then the maximum power of the fuel/air expansion gases would eject out the valve (path of least resistance) rather than drive the piston down to the bottom of the stroke where presumably at BDC or thereabouts the cam lobe begins to open the exhaust valve for the impending exhaust stroke.

    Maybe the dealer is correct, maybe there is an acceptable tolerance with regards to relative cam and crank marker positions. I just found it odd that there is grove and point (akin to a rifle sight) to pinpoint the crank-mark position yet Honda are saying that the mark being outside the pointer is within the scope of the timing being correct.

    I'll sleep on and it might become clear in the morning lol
  4. Doc Expert Advisor ★ ★ ★ ★ ★

    Matt Peterborough
    To me that timing belt looks out by one tooth. Honda may be right in saying it's within tolerance i.e the cycle of the cylinder isn't affected as it still works, but that doesn't mean it's right.

    Personally I'd adjust it and see how it lines up then make a decision from there.