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  • pinchvalve

    Aug. 31, 2009 7:12 p.m. pinchvalve SuperDork

    I am just about done with fixing the MR2, but I am having issue with the timing. I had the timing belt off, as well as the cams, so I had to start from scratch. According to the BGB, I set the pistons at TDC. Check. I can see the cam in the right place through the oil hole and the pointer aligns with the correct line on the pulley. The dimples in the cam gears are aligned in the right spots. The dimples on the distributor line up just fine. The motor starts and idles nicely. Even kicks down after warming up. The only issue is that with a timing light, I am seeing nothing of the timing marks at all. They are nowhere in sight. Almost like it is set right, just 180 degrees out. Is that even possible and if so, WTFDODAI?

    The only thing that I can think of is that the jumper wire I am using at the diagnostic port is too heavy duty and not doing what it is supposed to. I see no difference in how the car runs if I remove the wire. I will try something smaller gauge and shorter.

  • Dr. Hess

    Aug. 31, 2009 7:25 p.m. Dr. Hess SuperDork

    It ain't your jumper wire at the diagnostic plug. All it does is short one pin of the ECU to ground.

    You do have the timing light on plug #1, right? And this isn't one of those fancy timing lights with the knobs on it is it?

  • mad_machine

    Aug. 31, 2009 7:51 p.m. mad_machine SuperDork

    Yes I think it can.. I remember my father dropping the timing gear into my old Type 1 engine 180out... just had to reindex the distributer oddly

  • TJ

    Aug. 31, 2009 8:26 p.m. TJ HalfDork

    Does the car have a wasted spark ignition system? I don't see how it would run as the spark would occur at the top of the exhaust stroke not the compression stroke. So if it was timed 180 with a standard points type ignition out you could make it work be switching plug wires around.

  • Jensenman

    Aug. 31, 2009 8:53 p.m. Jensenman SuperDork

    I have done dizzy ignitions 180 out, you usually get some nasty backfires.

    A possibility: could the outer crank pulley (the one with the timing marks) be installed 180 degrees out? That's easy to do on a rotary (remarked the voice of experience). The bolt pattern is offset so your chances of screwing up are less but it's still possible to have it wrong by 180 degrees.

    Also, I have seen bonded rubber balancer 'outer' rings 'slide' on the inner part, meaning the timing marks aren't even in the same county.

  • 4eyes

    Aug. 31, 2009 10:24 p.m. 4eyes New Reader

    Yes its way too easy to be 180 out. Remember your cams rotate twice for every time the crank rotates once.

  • 2002maniac

    Aug. 31, 2009 10:35 p.m. 2002maniac Reader

    Try putting the timing light on your #4 wire. If you see the timing marks, you're 180 out.

  • poopshovel

    Sept. 1, 2009 8:46 a.m. poopshovel SuperDork

    And this isn't one of those fancy timing lights with the knobs on it is it?

    FUNNY! This happened at midnight on Sunday when we fired up our LeMons car. "WTF!?!? The timing keeps CHANGING!!!"

  • Autolex

    Sept. 1, 2009 10:26 a.m. Autolex Reader

    2002maniac wrote:

    Try putting the timing light on your #4 wire. If you see the timing marks, you're 180 out.

    IF the motor fires 1-2-3-4 (or 1-3-2-4)

  • RobL

    Sept. 1, 2009 10:37 a.m. RobL Reader

    Yeah, it sounds like you are 180 off.

    The simple fix is to use the opposite plug wire. The firing order is 1-3-4-2, so you can use the #2 or #3 wires instead of the #1 and you should see the marks. You can't use the #4 because it fires at the same crank position as the #1.

  • 2002maniac

    Sept. 1, 2009 11:50 a.m. 2002maniac Reader

    Autolex wrote:

    2002maniac wrote:

    Try putting the timing light on your #4 wire. If you see the timing marks, you're 180 out.

    IF the motor fires 1-2-3-4 (or 1-3-2-4)

    Oh duh, my mistake. Most motors fire 1-3-4-2 though.

  • mainlandboy

    Sept. 1, 2009 2:37 p.m. mainlandboy New Reader

    4eyes wrote:

    Yes its way too easy to be 180 out. Remember your cams rotate twice for every time the crank rotates once.

    Other way around. Crank turns twice for the cams to rotate once.

  • 4eyes

    Sept. 9, 2009 2:53 a.m. 4eyes New Reader

    Cam pulleys are half the diameter of crank pulleys. Thus the cam has twice the rpms of the crank.

  • keethrax

    Sept. 9, 2009 8:52 a.m. keethrax New Reader

    4eyes wrote:

    Cam pulleys are half the diameter of crank pulleys. Thus the cam has twice the rpms of the crank.

    You still have it backwards. Cam pulleys are bigger.

    (not my picture...)

  • iceracer

    Sept. 9, 2009 10:39 a.m. iceracer HalfDork

    4eyes, you need to go back to auto mechanics class and stay awake.

  • 4eyes

    Sept. 9, 2009 9:09 p.m. 4eyes New Reader

    Your RIGHT I'm WRONG! I don't know what the hell I was thinking. Bass ackwards.

 
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