2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.

What does Top Dead Center mean to a rotary??

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Old 05-20-03 | 12:34 PM
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What does Top Dead Center mean to a rotary??

I searched and didn't come up with anything. How do I turn the motor to top dead center so I can install the distributor(running with a carb, so no CPS)?? Thanks

Ary
Old 05-20-03 | 09:18 PM
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anybody? anybody? bueller?
Old 05-20-03 | 09:28 PM
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TDC is when the trailing (yellow mark) on the pulley is lined up with the pin I believe.
Old 05-20-03 | 09:31 PM
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I suppose it would help if that pulley wasn't sitting on the ground Is there anyway to know which way it lines up on the crank shaft??
Old 05-20-03 | 09:36 PM
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It wil only install one way, the holes for the pullies are staggered.
Old 05-20-03 | 09:37 PM
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I've heard people say it only goes on one way....the pulley that is. I've taken one off, but haven't put it back on....
Old 05-20-03 | 09:51 PM
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its TRUE the holes are staggered, I didn't know this and had a hell of a time getting the thing on... and then I realized the problem.. lol
Old 05-20-03 | 09:56 PM
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Yeah, they make it easy so stupid people like us wont mess it up
Old 05-20-03 | 10:13 PM
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the hub for the pully has an alignment mark on it. (drilled divot on its face) That mark needs to be aligned with the timing mark on the front cover. Then you can stab the distributor without any problems.

It's four friggen bolts to pull the pulley off the hub... Why do so many people try and do bullshit looking through the spark plug holes for apex seal tricks and such? Its so damn easy setting TDC its stupid to do it any other way than the right one.
Old 05-20-03 | 10:35 PM
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Uh yeah, there are notches on the pulley too, so why the hell would you pull the pulley?
Old 05-20-03 | 11:10 PM
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because none of the notches are TDC. You can guesstimate where the right tooth is, or you can stab once and get it right the first time.
Old 05-21-03 | 12:22 AM
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Originally posted by Jimmy325i
stab the distributor without any problems.

Whats a distributor?.......

Jarrett
Old 05-21-03 | 12:24 AM
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I have one......on my ROTARY
Old 05-21-03 | 12:26 AM
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Not on your 2nd gen you dont...Unless there is some distributor mod I am not aware of.

*edit* just noticed you were carb and no ECU.

Okay..So you do have a distributor. My bad.
Old 05-21-03 | 12:30 AM
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Also if you have your yellow mark on your pulley aligned to the timing mark, thats 5 deg. ATDC. The next mark is red, which is 15 BTDC. So thats 20 degrees. Measure the distance between the 2, divide by 4. Then take that number and run it back from the yellow mark. Align that with the timing mark. Presto. TDC.

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Old 05-21-03 | 12:34 AM
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Originally posted by marcus219
TDC is when the trailing (yellow mark) on the pulley is lined up with the pin I believe.
Again, that would be 5 DEG ATDC.

Repeat.. 5 DEG ATDC.

lol!!!.......

Jarrett
Old 05-21-03 | 01:25 AM
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Originally posted by J-Rat
Not on your 2nd gen you dont...Unless there is some distributor mod I am not aware of.

*edit* just noticed you were carb and no ECU.

Okay..So you do have a distributor. My bad.
My european 86GXL came with distributor and its fuelinjected, it also has butterflies that doesnt get stuck aluminum hood, rear seats and aero package, All stock
Old 05-21-03 | 01:41 AM
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Okay okay...I made a mistake. One I ALREADY admitted to. Wasnt the first, wont be the last.

At least MY mistake didnt cause a space probe to crash land due to the GLARING differences between the metric and english systems.

Sheesh!

Jarrett
Old 05-21-03 | 01:41 AM
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With the amount of time and frustration it takes to get your head down in there and mark and measure.... I could have the car running. Its four 10mm headed bolts. Really simple... They're not even all that tight.

Does the FSM tell you to whip out some tape measure? Didn't think so....

Now, if you had an aftermarket pulley which was labled with TDC... USE IT. Everyones always crying about how hard it is to start rebuilds and I'm thinking this is a major cause of that. It's just funny that mine fired right up.
Old 05-21-03 | 01:43 AM
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Originally posted by Jimmy325i
Does the FSM tell you to whip out some tape measure? Didn't think so....

Thats because the FSM doesnt require any setting on the motor at TDC.

Its called a MOD!

Jarrett
Old 05-21-03 | 01:47 AM
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Originally posted by J-Rat

At least MY mistake didnt cause a space probe to crash land due to the GLARING differences between the metric and english systems.
Ok you lost me buddy, now im confused

Metric RULES
Old 05-21-03 | 01:48 AM
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Originally posted by Kim
Ok you lost me buddy, now im confused

Metric RULES
You live in a cave?

Remember the space probes we launched at mars, that crashed?

Anyways, this is completely OT. Not nice to thread hijack.

Jarrett
Old 05-21-03 | 01:49 AM
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But you do have to stab the CAS at TDC... or distributor in this case.

I've never heard of the one tooth off mod for better performance. Usually that results in carb fires or a motor that doesn't rev up for ****.
Old 05-21-03 | 01:51 AM
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Uhh those !!!! No I dont remember as I really dont watch tv a whole lot, Maybe I should live in a cave, if it wasnt for those americans I would J/K
Old 05-21-03 | 01:56 AM
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Originally posted by Jimmy325i
But you do have to stab the CAS at TDC... or distributor in this case.

I've never heard of the one tooth off mod for better performance. Usually that results in carb fires or a motor that doesn't rev up for ****.
You need to read the FSM, they tell you to stab it at the leading mark, which is *NOT* TDC. Want me to post a picture?


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