Need help getting sbc to start/run

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I just replaced the camshaft in my 350. The timing set is new and the cam and crank gear are properly lined up with the dot on each gear pointing at each other. I verified the harmonic balancer and timing cover marks are correct using a piston stop and degree wheel. I double checked every valve setting the preload initially at 1/4 turn. The engine is fuel injected and the distributor is supposed to be set at 0 degrees. I set the distributor at zero degrees for tdc on number 1 cylinder and i have the rotor pointing to the number one plug wire. I double checked the firing order and made sure it was good on the cap and that all wires were going to the proper plug. The issue is the engine does not want to start it just cranks. It has throttle body injection so i can watch the fuel injectors spraying fuel. I can get it to start with starting fluid but it will quickly start backfiring through the intake. I tried putting the distributor in 180 from its current location just to see what would happen and it’s definitely wrong as it immediately spits out the intake when using starting fluid. Im not sure what else to do. The engine ran before i replaced the camshaft.
 

OVERKILL

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Stupid question, but are you sure you have the plug wires going the right direction on the cap? It definitely sounds like something isn't firing when it is supposed to.

What camshaft did you use BTW?
 

joegreen

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Yes the plug wire firing order is going clockwise when looking down from the top. Used a melling ccs-2 camshaft.
 

joegreen

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Are you getting spark and fuel? Distributer 180* off?
yes i can see the fuel injectors spraying and it is getting spark because it kind of runs. I tried turning the distributor 180 from where i had it set in case i had it set wrong. When i did that though it was clearly in the wrong position as it did not run at all and immediately spit out the intake.
 
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Did you adjust the valves ¼ turn past zero lash with the lifters primed or dry?

I have always presoaked new lifters before installing them, then primed the engine until I get oil to the rocker arms then and adjusted the valves ½ a round past zero lash.

If dry, I'll go to ¾ to 1 turn depending on the application and specs.
 

joegreen

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Did you adjust the valves ¼ turn past zero lash with the lifters primed or dry?

I have always presoaked new lifters before installing them, then primed the engine until I get oil to the rocker arms then and adjusted the valves ½ a round past zero lash.

If dry, I'll go to ¾ to 1 turn depending on the application and specs.
Initially i adjusted them dry. But i have maybe 10-20 seconds of run time so there may be some oil in them now. I tighten the lifter adjustment nut until the pushrod just stops being able to be lifted up and down with my fingers then I went 1/4 turn extra.
 
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There's no way a small block chevy hydraulic flat tappet cam valve lash is too tight at just 1/4 turn past zero lash. That cam is close to stock or just s step above. Out of the couple dozen engines I've assembled or had a big hand in...I've never adjusted less than 1/2 turn past zero lash on hydraulic cam.
 

joegreen

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Ok the issue has been solved. I loosened all the rockers and set them to zero lash when moving the pushrod up and down. I must have tightened to much on the adjustment nut. Thanks everyone who suggested valve lash.
 
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Most books say to spin the pushrod while tightening the nut to find zero lash. An old mechanic suggested going up and down instead. Hasn't failed me yet.
 

OVERKILL

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Most books say to spin the pushrod while tightening the nut to find zero lash. An old mechanic suggested going up and down instead. Hasn't failed me yet.

Yep, I was instructed by my cam grinder to spin the pushrods with my fingers while tightening the nut until I started to feel drag. As soon as I felt drag, go 1/4-1/2 a turn and stop. I always erred more toward the 1/4 than the 1/2.
 

joegreen

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Most books say to spin the pushrod while tightening the nut to find zero lash. An old mechanic suggested going up and down instead. Hasn't failed me yet.
Both ways will work but I believe its much easier for a novice (like me :ROFLMAO:) to mess things up using the spin method vs the up and down method
 
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