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1974blackz28 05-20-2010 08:29 PM

First Start Up Problems
 
I just rebuilt my 350 and dropped it in and everything is ready to go except it wont start, getting spark I poured fuel down the top I can even see the carb spraying it as I manually prime it.

I have a High Torque starter and for some reason it isnt turning the engine over very fast but I see sometimes it backfires out of the carb so I dont think its a problem.

The battery is low and I was doing it through jumper cables and it made no difference it went the same speed.

What am I missing any suggestions?

va4cqd 05-20-2010 08:34 PM

the timing is way out. far too advanced

1974blackz28 05-20-2010 09:06 PM

but when I retard it nothing happens and the starter seems like at one point it revolution it has no problem then when it reaches the other it slows down.

techinspector1 05-20-2010 09:18 PM

Remove spark plugs.
Remove valve covers.
Remove distributor.
Standing at the front of the motor, at the water pump and looking toward the rear of the motor, #1 cylinder will be on your right, the first one, just behind the radiator. The next one to the rear will be #3, then #5, then #7 will be the last one on the driver's side, next to the firewall. Looking on the other side of the motor, the passenger side, the front cylinder will be #2, the next one to the rear will be #4, then #6, then #8 all the way to the rear against the firewall. Do whatever you have to do to get this all fixed in your mind. If you have to make a diagram on a large piece of paper and sit it against the carburetor, then do it. Knowing which cylinder is which cannot be over-stated.

Also, knowing which way the crankshaft turns and which way the distributor rotor turns cannot be over-stated. As you are standing at the water pump, the crankshaft turns clockwise, the same way the hands on an analog watch or clock turn.

If you were to climb up on top of the motor from the front and look directly down on the distributor with the cap off, you would see the rotor turning clockwise also. See this cute little animation.....
http://www.boxwrench.net/specs/chevy_sb.htm

With a socket and long bar with a ratchet attached to the bolt head that holds the harmonic damper onto the front of the crankshaft, turn the crank clockwise while a friend holds his thumb over the #1 spark plug hole. Using the starter for this operation WILL NOT WORK. When your friend feels air pressure beginning to build under his thumb, that means that both valves are closed and the piston is coming up on the compression stroke of #1 cylinder. Watch the harmonic damper and you will see the notch that is cut into the outer ring of the damper come up to the top. When that notch is at the top, STOP. You are now at approximately top dead center on #1 cylinder. It doesn't have to be EXACTLY at top dead center to adjust the valves.

Make a mark on the harmonic damper ring so that you can reference this TDC position again later. Either use a yellow crayon like they use at the tire store or a piece of tape placed at that position or whatever your mind can come up with. Make the mark at the top of the harmonic balancer inertia ring. We are going to refer to this position as NORTH, because if you got down on your knees and looked at the harmonic damper from straight on, like you were looking straight through the centerline of the crank, this would be the NORTH position.

Loosen both adjusting nuts on both rockers on #1 cylinder until the rockers are loose on the studs. Have your friend hold his finger on the tip of one of them so that he is pinching the rocker arm down onto the tip of the valve, holding it tightly. Now, you grasp the pushrod for the rocker he is holding down and jiggle the pushrod up and down while using a socket wrench to slowly tighten down the adjusting nut until all the slack is removed and you cannot move the pushrod up or down any longer. Be delicate here. This is not a strong-armed operation. You are simply taking all the slack out of the pushrod and getting the rocker adjusting nut very slightly tightened down against the trunnion of the rocker arm. Now, make 1/4 turn more on the adjusting nut.....1/4 turn.....90 degrees......OK, that valve is done. Now, move over to the other valve on #1 cylinder and repeat the operation.

You may have heard that you can rotate the pushrod with your thumb and forefinger until the pushrod gets tight and use that for adjusting the valves. While that may work for someone who builds motors day in and day out for a living, it WILL NOT WORK for someone like you who has no way of knowing how much resistance he should be feeling for. Jiggling the pushrod up and down is BULLETPROOF and can be done successfully by even a first-time builder.

Now, you have both valves adjusted on #1 cylinder. With the socket and ratchet on the harmonic damper retaining bolt head at the crank, turn the crankshaft 1/4 turn clockwise. That will mean that the mark you made on the damper ring will move clockwise from NORTH to EAST.....STOP. Make another mark on the damper ring at the straight-up position. Now, you will have a mark at EAST and a mark at NORTH.

You have moved the crank 90 degrees and into the next cylinder's firing range. There are 720 degrees in a full cycle to fire all 8 cylinders, so turning the crank 90 degrees at a time will allow us to adjust the valves on all 8 cylinders with just 2 full turns of the crank. If you knew that a small block Chevy's firing order is 1-8-4-3-6-5-7-2, then you would know that it is #8's turn to fire. Go to #8 and loosen both adjusting nuts, just like you did on #1. Have your buddy hold the rocker down against the valve stem while you jiggle the pushrod up and down to remove all play, all the while slowly turning the adjusting nut to remove the play. When all the play is removed, tighten the nut another 1/4 turn. Move on to the other valve on #8 and do the same.

Now, you have adjusted the valves on cylinders 1 and 8. Put the socket on the crank nut and turn the crank 1/4 turn to the right (clockwise, just like before). Place a mark at the top of the inertia ring like you did last time. This mark will be at NORTH. The mark you had at EAST will move to SOUTH and the one you had at NORTH will move to EAST. Following the firing order, we will now go to cylinder #4 and adjust both valves. Then we will move the crank 1/4 turn and make another mark and do cylinder #3. Then we will move another 1/4 turn (the crank has marks for each 1/4 turn now) and do cylinder #6. Then we will move the crank another 1/4 turn and do cylinder #5. Then we will move the crank another 1/4 turn and do cylinder #7. Then we will turn the crank another 1/4 turn and do cylinder #2. Then we will turn the crank another 1/4 turn and be back to firing on #1, where we will stab the distributor and install the retaining clamp and bolt. We will leave it a little loose so we can rotate the distributor housing. You may have to use a long screwdriver to line up the slot in the distributor driveshaft as you look down into the hole where the distributor goes.

As if we were standing on the motor and looking down on it, we will want to point the rotor tab at #1 cylinder, approximately 5:30 O'Clock if you look at a clock face. Position the distributor housing so that you can twist it both ways without the vacuum advance can hitting on the intake manifold. Replace valve covers. Replace spark plugs. Using your longest spark plug wire, plug it into the 5:30 position on the cap, co-inciding with the tab on the rotor at 5:30 and run the other end of the wire to #1 spark plug. The longest wires will be for #1 and #2. The next longest wires will be for #3 and #4. Next longest for #5 and #6. The shortest wires will be for #7 and #8. Going around the cap in a clockwise manner, the next hole in the cap will take the wire for #8 spark plug, then #4, then #3, then #6, then #5, then #7, then #2.

Now, depending on where the timing tab is on your motor (there were 3 different positions used), you might have to rotate the distributor housing a little one way or the other to get the motor to fire off, but unless I miss my guess, SHE WILL FIRE OFF THIS TIME. Have a timing light affixed to the #1 spark plug wire, adjust timing and lock the distributor down.

A little more info about the different timing positions. Like I said, there are 3 different ones. If you were to stand up over the motor and look down on the harmonic damper, there is a 12:00 Noon position, a 2:00 O'Clock position and a 2:30 O'Clock position. Through the years, the timing tabs and front covers get mixed up on these motors, so you really should find top dead center and use the proper mark on your harmonic damper to line up with the timing tab on your front cover. Here is the procedure for doing this with the motor assembled that I wrote for the Crankshaft Coalition Wiki....
http://www.crankshaftcoalition.com/...top_dead_center

1974blackz28 05-20-2010 09:26 PM

I own the box wrench dvd I followed those instructions I just dont know why its moving so sow while cranking and sometimes backfiring out the carb

74chevyflat 05-20-2010 09:41 PM

make sure your distributor is pointing at number one cylinder. meaning the rotor to the correct pole on the cap. the number on POLE should be the one next in line right after the vacuum modulator. have u gotten this thing to start yet> IF NOT TRY THIS. FAIL PROOF. u might even be out 180*. does is spit out the exhaust and carb? hahah reminds me of a muffler load up i had one time. hehehe dad came out the house thinking someone was shooting. hehehehehe funny but not at the time i was deaf. BOTH flowmasters POPPED sounded like a 50cal. double barreled gun lol. MY ears :D were ringing the rest of that day

74chevyflat 05-20-2010 09:46 PM

need help i see u reviewing maybe i coul walk u through it.

1974blackz28 05-20-2010 10:01 PM

Yes the Rotor is pointed at the number one cylinder

74chevyflat 05-20-2010 10:24 PM

did u by any chance line up the camshaft and crank sprockets? dot to dot. another thing. another fool proof is using a wire tie down the spark plug hole. when it reaches the very top it should be TDC, try it if it still pops, its 180 out. this means take the distributor hold don clamp loose and remove. lift the distributor and turn the rotor 180* around from the initial spot it was at. give it a try.


if none of the above works. your valve adjustment may need some checking. u may have your lifters bottomed out.

this may require u to loosen all the rockersto a snug fit. try cranking it and if it cranks let it run a lil bit may get some oil everywhere though. this will pump the lifters back up where they should be. If u dont mind the oil u can adjust while running. tighten till the clatter goes away and give it another 1/4 turn.

327NUT 05-21-2010 01:50 AM

A little thing but very important...do you have a GOOD ground cable hooked up between chassis and engine block? As Tech pointed out everything in his post. Just start at the beginning, and as asked are you sure you have the crank and cam gears lined up?

You may have to take some of it apart to check things but it's better than just cranking away and wiping your cam lobes off. A fresh engine needs to fire pronto to get the juices flowing and break in that cam.

BBCMudbogger 05-21-2010 06:50 AM

Don't stick anything in the spark plug hole.....#1 TDC is no good unless it is on the compression stroke. Put your finger over the spark plug hole tight. When the compression pushes your finger out you are good.Then go through your cold timing process. If all is good there your valves are too tight. If you have been messing with this thing cranking and cranking you probably do not have any assembly lube left on the cam.Not to mention cylinder wwalls washed clean with all of the gas being pumped into it.

V8 Super Beetle 05-21-2010 12:13 PM

I used the same DVD to help me with my rebuild and have had great success between this board and the DVD.

Did the bearing clearances check out OK when you were rebuilding it?

Did the rotating assembly / short block (pistons installed in bore, on crankshaft, with rings) turn over easily? It should've taken around 20 ft lbs. of torque to turn it over.

Is the starter new?

How well did the battery turn over the engine before it got drained some having starting issues?

With the back firing issue, like the guys have mentioned, double check that you setup the wiring and timing correctly. Do it over if you have to. Watch that portion of the DVD again and again. I must have watched the DVD 20 times before I started my rebuild and it fired up right away.

You'll get it. Hang in there.

oldbogie 05-21-2010 01:58 PM

Quote:

Originally Posted by 1974blackz28
I just rebuilt my 350 and dropped it in and everything is ready to go except it wont start, getting spark I poured fuel down the top I can even see the carb spraying it as I manually prime it.

I have a High Torque starter and for some reason it isnt turning the engine over very fast but I see sometimes it backfires out of the carb so I dont think its a problem.

The battery is low and I was doing it through jumper cables and it made no difference it went the same speed.

What am I missing any suggestions?

Chevy has a little surprise. When you put it together with the timing marks on the cam and crank gears facing each other, the engine is set with number 6 in the firing position. If you leave it there and drop the distributor in timed to number 1 firing, it's 180 degrees out.

There plenty of other reasons but let's start with whether that is a situation or not for your set up.

Bogie

T-bucket23 05-21-2010 02:45 PM

You can test to see if the slow crank is due to ignition timing by eliminating power to the distributor. As mentioned above you need to get this fired as cranking will hurt the cam eventually.
My guess is you are out of time, many people have issues with this.

1974blackz28 05-21-2010 08:28 PM

Ok guys it was started up but, I think im having heat soak problems I hear a click from the starter when its hot, If so I already bought a ford solenoid but before I install it does this sound like heat soak?

Also I only let it run for 30 because it was in my garage ( I want to tow it out to a parking lot) because its too loud.

A local mechanic said I can let the car Idle for 5 minutes while I adjust the timing then do the cam break in is this true?

Also on my friends project car he rebuilt the engine and its popping through the car as he accelerates im telling him its a flat cam lobe because he decided not to break it in, can anyone verify that for me.


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