CC503 Cam Problem...Won't Start
 

ok I've torn the car down to the timing gear twice now....the first time it would backfire out the intake....so I tore it back down....I retimed it or so I thought and put it together and now it is backfiring out the exhaust....can someone help me out with this....


I'm assuming it needs to be at TDC#1 right? and is there anyway the nonvented opti could be off like would I need to pull the cap and adjust the rotor button?


Please Help this thing is starting to make me angry:bang:

Have you checked your rockers? sounds like you might've missed one or two, or have a couple WAY to loose.

And to answer your question, the non vented opti can ber off. Its a pretty easy mistake to do even though it is only suppose to fit one way. Look at the splines on the opti shaft there in one odd spline (double wide) that goes into the center of the cam gear one way (it will have the wider tooth cutout) People tend to force it together when they are missing the splines by just a little, it will just slide together.

Make sure your timing set is right, if it were a 95+ one the opti will fit but the center hole would be to big and not turn the optispark. I doubt this is the case tho.

The car is a 95 Z28 and has a Nonvented Opti I will check again about the opti positioning and try to retime it again...and to be sure base it off of #1 TDC with the button pointing toward #1 wire?

What exactly do you mean when you said you "retimed" it? :confused: Timing is 100% controlled by the PCM. If the opti keyway is installed into the cam gear correctly and you had the cam/crank gears lined up dot-to-dot, you can't screw up the timing.

In your case it is likely something simple. Check, double-check, and re-check your plug wires and routing. Had a similar issue and it turned out I had two plug wires crossed.

What did you set your valve lash to?

how did you have the dots on the timing chain in corrolation to the #1 or #6 piston?



Dot to dot is #6 TDC (cam at 6 and crank at 12)


#1 TDC (cam at 12, crank at 12)

same here. But you have a NON-VENTED opti on a 95?? which dowel pin do you have in the cam?

ironically enough the cam I bought had a broken dowell pin and my 95 has a non vented opti

i tried it at both #1 TDC and #6 TDC (#1 being cam dot was at 12 o'clock and #6 being dot to dot)

at #1 the engine backfires out of the intake and at #6 it backfires out of the exhaust....as far as valve lash I have loosened up the rockers thinking they might be too snug and it still won't crank only backfiring and im lining up the opti's "double pin" to the Double slot on the cam gear and still only backfiring.....I have no clue I have torn this thing apart so much I could do it in my sleep now...some one please shed some light

Did you rerun your plug wires to make sure they are on in the right order?

what method are you using to get your rockers right?

I am tightening them until the do not twist while that correlating piston is at TDC then leave them alone and I have checked my wires and they are on correct

I was reading over Shbox's web page and may have the Rocker arms too tight gonna go try that one more time just to be sure I loosen the Rockers then place at TDC then tighten til I fell drag the immediatly add 1/2 turn then the preload should be set?

TDC on the compression or exhaust stroke? Do you have a fully degreed balancer?

stock....and it is TDC on compression

Use method 1 or method 3 if you do not have a fully degreed balancer.

I used to have a fully degreed balancer on a bbc and I used method 2 to adjust the lash of my solid lifters. You MUST have a fully degreed balancer to use this method.

Brett

Its a 95 I HOPE YOU HAVE VENTED OPTI ON THERE.?

if YOUR using stock rocker arms the easiest way and pretty much works everytime is to count 4 threads down on the rocker stud while your tightening the rocker nut. So once you see 4 threads above the nut your good to go.. At the dealer this was the easiest way and many other shops even use this method. IF your using poly locks then use shbox.com methods they work well with pics. But for timing you can just pop up #1 which if your lookin at the engine it will be on the right of you and 1st piston. Pull the plug and put a hanger in the hole and slowly I REPEAT SLOWLY turn the engine until you feel it stop, then turn the engine back slow by HAND and pull the hanger out. Then after that you can pull the timing cover off and everything again and then check the timing marks and see if they are spot on.

Hey asshole you are the one I got the cam from this shit is your fault....LOL J/K Yeah rob they are on stock rockers and I'll try your 4 threads trick after I redid the rockers this last time i got no backfire but now it acts like its getting no fuel I wish this nightmare would end finally by the sound of that cam loping....but sadly im stuck still

and it has a non-vented opti thats the way I bought it

ok i tried the 4 thread suggestion and the result was more backfire

What the hell is wrong with it