Thread: small block rebuild first fire

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Lookin for some help on my 350.
Fully rebuilt sb. It is my first rebuild. But I was extremely careful and triple
checked my every move.
Stock crank. Stock cam. Stock heads(new valves and springs) new rods and
rocker arms. +.040 pistons. New plugs. New distributor. Starter is new but
it is stock. New battery.

So after spinning the oil from the distributor port I installed the distributor.
placed it in at tdc facing piston #1. Have not advanced or retarded it all.
I turned it over and few times without the plugs in to seat the new rings.
After I put the plugs in it almost fired but it struggled for a couple
rotations than it was dead in the water. Smoke from thr starter. Do
I need a high torque starter because of the oversized pistons??
More compression so that would make sense. Or am I missing
something? Any little bit of help would be greatly appreciated.

Thank you

Originally Posted by constantinou220

So after spinning the oil from the distributor port I installed the distributor. placed it in at tdc facing piston #1.

There are 720 degrees in one complete cycle, so each piston comes to TDC twice in each cycle. You have to make sure that you are phasing the rotor with the piston on the compression stroke, not the overlap period. Remove all spark plugs. Put a socket and breaker bar on the harmonic damper retaining bolt head and turn the motor clockwise manually while one of your buddies holds his thumb over the #1 spark plug hole. When your buddy feels pressure on his thumb, the piston is coming up on the compression stroke. Continue turning the crank slowly, while watching the harmonic damper TDC groove and lining it up with TDC on the timing tab which is on the front cover. STOP. Install the dizzy so that the rotor is pointing to 5:30 O'Clock as you look at the motor from above. Install the dizzy body leaving plenty of room for the vacuum can to miss the intake manifold and the firewall rotationally as you turn the dizzy back and forth to adjust the timing once you get the motor running. Install the dizzy cap and run your first wire from that 5:30 position to the #1 spark plug. Now, run the remainder of wires clockwise around the cap according to the firing order 1-8-4-3-6-5-7-2.

Originally Posted by constantinou220

I turned it over and few times without the plugs in to seat the new rings.

Not a good idea. The cam and lifters are lubed from oil being thrown off the skirts of the pistons and from splash in the oil pan, which both require considerable engine speed over simply being turned over with the starter. You may have screwed the pooch already by galling the lifter crowns from lack of lube. Maybe, maybe not, how's your luck?

Originally Posted by constantinou220

After I put the plugs in it almost fired but it struggled for a couple rotations than it was dead in the water. Smoke from thr starter. Do I need a high torque starter because of the oversized pistons?? More compression so that would make sense. Or am I missing something? Any little bit of help would be greatly appreciated.

The electrical system could be struggling due to lack of sufficient grounds, which happens often when a motor is dropped into a chassis after a rebuild, we forget to re-install the grounds. Charge the battery, install new battery cables (Use good quality cables, not some fosdick budget items) and install new ground cables from the engine block to the body and from the body to the frame. As I often say, a car cannot have too many grounds. Grind down to bare metal to install your ground cables, then smother the connections with RTV to prevent corrosion.

Here's some reading for you.....
http://www.crankshaftcoalition.com/w...ips_and_tricks
http://www.crankshaftcoalition.com/w...stment_SBC/BBC
http://www.crankshaftcoalition.com/w...op_dead_center

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Welcome to CHR!

Tech covered the bases. My first thought was that you're 180 out on the distributor based on your

Originally Posted by constantinou220

...placed it in at tdc facing piston #1

Also on the spinning the engine with no plugs. Instructions with new flat tappet cams today tell you to fire immediately, minimize cranking and to take it to 2000rpm for twenty minutes to help ensure the cam/lifters get broken in right. Anything else may have set you up to grind off a lobe or two in short order which means a total teardown to get rid of the ground up lobe(s). Roller lifters are the ticket with today's oils, but you may dodge the bullet if you run a heavy dose of ZDDP or a good racing oil.

The lack of good ground is a great tip, and hopefully you didn't totally smoke that starter. If you're lucky you just overheated it and it will still be OK. Cross your fingers as you turn the key the next time, but be ready for a drive to your favorite auto parts store. A stock starter will be fine for your engine, and use cable for your engine to frame ground, not those cheap mesh straps.

Let us know what you find when you check your distributor position vs #1 TDC Compression.

When I build an engine, I put some sort of heavy assembly lube on the cam, lifters and crank journals. Shouldn't hurt a thing, if the engine spins awhile, before it starts.

That's exactly what I did. Didn't turn it a hole lot. A couple cranks to see if it would fire. Any idea on the starter deal? Do I need a high torque starter? Mm

I don't think you need a high torque starter, your engine is stock so a stock starter should be adequate, First thing on your starter is check to make sure you have a good ground to your starter, and make sure you have a good battery cable between the positive post and the starter and they both are of adequate size. If that doesn't cure it and you are unsure how to test it remove it and take it to Oreilly or Autozone etc and have it checked before shucking out bucks for something that might not need replaced. My two cents worth..