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73-87 Chevy _ GMC Trucks => 73-87 Chevy & GMC Trucks => Topic started by: chevyh20 on December 05, 2008, 12:20:05 am
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hi, i need help . I just changed rotor, cap and spark plug wires on my 89 blazer 350 tbi. was running ok before i changed them, but the old parts were bad. so i put new ones on and now it wont run. It backfired a couple of times. and coughed out of the tbi a few times that is all. Heres the dumb thing i did, i did not note the position of the wires on the cap. but i have a book that has the matching cylinder #s so i was not concerned. i used electrical grease also when i installed the wires. thanks a lot for any help.
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I would pull them all back off the cap. Reference the book, and start over.
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You messed up your firing order. Put the engine on TDCC and see where the rotor is pointing. that is #1. From there arange your wires clockwise 1-8-4-3-6-5-7-2
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Finding TDC on an Engine-
REMOVE the number one spark plug on the right side of the engine as you face the engine. Find the timing mark on the harmonic balancer.
Take off the driver side valve cover and have a helper turn the engine over until you see the second valve back from the front of the engine open then just close (this valve is the intake valve) and will give you the correct compression stroke. Guys like Vile will probably have a remote starter to do this or he can probly do it eyes closed- lol
Then turn the engine over with a socket on the crank bolt and put a long screw driver in spark plug hole, so that as the crank is turned the screw driver starts to move back down. The pointer on the harmonic balancer will move towards 0 degrees as you turn the crank.
Now turn the crank backward until it stops moving up. This will be TDC on the number 1 piston... and the pointer should be on or near 0.
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Thanks for pointing me in the right direction guys. i did as you said. i took out #1 plug and put a finger over the hole while turning the engine crank. i turned while i could feel the compression just to the point where the compression stopped. Then i looked to where the rotor was to find my #1 cylinder on the distributor. i wired them up from there in order. It turned out the #1 was 180 degrees from where it was supposed to be. evidentally the distributor was not installed right at some point. i didnt know about this possibility. thanks again for steering me straight.
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got a funny feeling we will be hearing from him
again
Mark