how do u know when cam is in tdc

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racejunkie

New Member
hello all,

i have a 90 civic si with the d16a6. I purchased an exospeed reground stage 2 cam and an aem adj cam gear. I replaced them a year ago and haven't started the car yet. (wainting to paint the car). Now that I'm trying to get the car running, the car won't start. I remember having a hard time when I replaced them becasue the old stock cam gear has the notch for tdc. But the new gear didn't have it.

Anyone out there know how to get the car timed right. I checked my firing order, and reversed the distributor thinking it could be 180 out. But still nothing. I do have spark and have replaced the plugs and put new gas in it (parked it with fumes). I also tried using starting fluid. Not even a sputter. My only thoughts are that when I installed the belt the head wasn't in tdc (the bottom end was at tdc #1 cyl).

How do you know when the head/cam is in tdc?

Please Help!!! and thanks!!!
 
There's marks on the cam gear and timing arrows on the plastic behind the cam gear. Just line them up.

Otherwise, keyway is usually up.
 
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if your new cam gear doesn't have a mark at about the 7 o'clock position, you need to place a mark on the gear like the picture below and line that mark up with the pointer on the inside back timing belt cover - on the crank pulley, the TDC mark is the white mark off to the right of the 3 ignition timing marks - line it up with the pointer on the timing belt cover

D16A6camgear.jpg
 
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re check your valves, you could have a bunch still open, do this after you figure out the timing.
 
Crank should be at TDC, cam should have both followers on the bases of the lobes on #1 cyl. (eng rotates ccw from cam gear side and cw from dizzy side)

One thing that I've found was that if the injectors had been sitting for long periods, the pintles could be all gunked up and stuck from spraying.

Does it turn over?
Will it fire with some carb cleaner shot in the T/B?
If so, you may have to pull the fuel rail and then injectors to soak/clean the pintles in the end. LIGHTLY press the pintles in a few times to make sure they move and then pull the little orange cone filter/screens on the top of the injectors too.

If no spark. Check the rotor to see if the little screw holding it on was tightened too tight cracking the housing leading to a short that can drive you nuts.

You may have to go over things again to refresh your memory from sitting so long. I know I do just after a day or so.. (OH, that wire is off!)

E
 
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