I replaced the timing gear and chain on my sons 83 f150 with a 351w in it. I have spark and fuel, will not start, the crank shaft mark faced up and cam faced down, what else can it be?

 

Did you pull the dist while doing the chain/gears swap?

 

no I didnt, should I have done that?

 

It ran before you changed the gears and chain. If you didn't pull the distributor, and you have spark and fuel, and it won't run, seems to me the cam gear must be off a tooth (or more).

Put a timing light on it and crank it. If your timing is now way-the-heck off, the cam gear is off a tooth or more.

 

Not required, and it rules out having the dist installed wrong. In theory, the cam and dist are still timed correctly with each other, assuming it ran before the chain/gear swap.
What was the reason behind the replacement of these items? If the cam gear went "redneck" (toothless) it is *possible* that some valves were damaged when this occured. Rather rare, but I have seen it happen.

Does it act like it wants to start, or just cranks like there's no fuel or fire? If the chain was starting to get a lot of slack in it, or the replacement cam gear doesn't have the same cam setting, the ignition timing could be way off.

I'd follow Jim's advice and check the timing with a light, to see what's going on there.

 

Thanks for the help I will try the timing light, It was running very rough, when I pulled the timing gear off there were some teeth that were missing half, and the chain was loose.

 

Ok did the timing light showed to be 8 degrees advanced, should be good? has spark and fuel will not start, what is next? I replaced the control mod because wasn't getting constant spark, now have it. Have done complete tune up also plugs cap rotor wires, I can not think of anything else. Need some help.

 

Is it possible that you put your chain a tooth or more off? I know that can cause issues. How new is your carb?

 

How old is your balancer Dan?

 

8 degrees advanced should be fine. Unless your timing was WAY off before you changed the chain and gears, I would say you have the gears and chain correctly installed, not off a tooth.

I would suggest checking the harmonic balancer to see if the outer ring has rotated. This is pretty common on our era engines. This is why ArdWrknTrk is asking about the age of your balancer. You could pull the #1 spark plug and turn the engine over by hand while watching through the plug hole and bring #1 piston up to TDC. Then check the timing mark and see if it is near zero. You may not be on the compression stroke on the first try, so if the mark is nowhere to be seen, go one more turn on the crank. This will be easier if you pull all 8 plugs to relieve the compression.

If you find that the timing mark is way off, then make a new mark on the balancer with a piece of chalk, or a dab of white-out, or something similar. Then put the plugs back in and reset the timing to the new temporary mark. If it runs, then you should replace the balancer, as it will continue to rotate and can slip until it hits the engine.

 

8* Before Top Dead Center...
Advanced is relative to stock cam timing.

 

I would highly suggest that you replace your balancer. Mine was good and then I heard some light metal on metal the other night. I found the rubber was totally gone and my outer ring on the harmonic was just slipping like a sumbitch.

 

Ok check everything over the weekend, still not running. I know the timing is correct, pullend valve cover off and turn motor over checking valve movement. All looked good and made sure I was on TDC and all marks were where they should be. I dont know what else it can be. If I replace the stock intake with an after market to take off all the vacuum BS, will I have to do anything else to the motor? But frist thing frist what is next to try?

 

Changing the intake "to remove all the vacuum BS" while the engine isn't running is NOT a good move.

The engine right now isn't running after having changed the timing chain, something during that change has caused this condition. You say yourself the engine was running poorly before this change but it was at least able to start and run.

To go changing even more stuff - unrelated to the first changes - creates the possibility of even more problems.

The vacuum stuff will not keep the engine from starting.

If it were mine, I'd try spraying some ether down the throat of the carb and see if it kicks, tries to start.

If it doesn't even try to start, that tells me of an ignition-related problem. I guess I'd then mark the distributor's exact placement, then move it around some as if adjusting the timing and see if anything changes, go from there.

If it tries to start with ether, that tells me of a fuel delivery problem, need to investigate there.

You are saying you have spark & fuel, but you need these in the proper amounts and at the correct time.

This could be caused by something stupid such as the spark plug wires installed incorrectly.

 

Was looking at changing after truck is running. I have sprayed ether and no change. I will recheck wires and go from there, thanks for the information.