Just a little advice. If you start gettting backfires through the carb, please make sure you have the throttle blades open. If you get enought fuel down in there and it backfires with the plates shut, you can literally blow the carb right off the top of the engine. Have you had someone crank while you watch with a timing light? Get it to about 12-14 btdc. If you're right at tdc you're probably still going to have a hard time. This sounds like 100% timing to me.

 

backfires through the carb usually mean off 180 degrees, remember the rotor turns clockwise if you turn the distributor a little towards the drivers side you are advancing the timimg, towards the passenger side and you are retarding it, did you set the valves cold? if so it should fire up.

 

I've seen them installed two teeth off and not fire.

I noticed that it would catch a little better with the cap turned to one side. So, I moved the shaft one tooth over. This time it would fire up if I had the distributor turned to the same side. Then, I moved the shaft over one more tooth. Bingo, fired right up.

 

It sounds like the wiring to the coil might be breaking down. You should have about 8 to 9 volts at the + side of the coil while cranking.

 

There's a lot of postings about this problem. If I have time tomorrow maybe I can get some references to them. Lars has a good article on finding TDC. Also, there's a nice graphic on getting the spark plug wires correctly connected. And of course, Lars has some good writeups about getting your distributor correctly positioned.

If you have a starting problem, I would not try to pour gasoline down the carb, or squirt gasoline from the accelerator bowls. (Well maybe I might do a little squirt from the accelerator bowl.) Use an aersol can of starting fluid. This is available at auto parts stores. I think the main buyers are diesel truck drivers. Its just magic to start lawn mowers after a long winter.

Anyhow starting fluid is ether. If the spark timing on your engine is anywhere close, it will fire on ether. If the spark is occuring and the timing is pretty close, if you spray ether in the carb, the engine will run. If your engine will not run with ether being sprayed into the carb, it most likely has a spark or serious spark timing problem. Pouring gasoline in a carb is not all that prudent. Too much and you flood the engine. A flooded engine is reluctant to start. Also if you pour some gasoline in, and the engine backfires, you get a flamming spray of raw gasoline shooting out of the carb. NOT GOOD.

The ether is pretty safe. It burns more like alcohol than gasoline - i.e a light vaporous flame. Just hold it at arm's length as you spray it in the carb. If the engine does backfire, you don't want to get burnt by the flame cloud. It'd be good to have a fire extinguisher handy.

 

Success!!!!

I just woke up the whole neighborhood and my kids (its almost 11:00 pm) but who cares! It started.

Turns out I had the valve settings all wrong. When I put the engine together, I used a new assembly manual (one that I saw recommended in Vette mag) and I noticed that its procedure was different than I had done on previous engines. But I followed the instructions and know I checked it a second time, so I thought I was right. But since I had tried everything else, I went back to an old book and did it their way, and it fired right up. What a great sound.

Thanks to everyone who helped out with suggestions. This forum is such a great place for info. Now I'm going to bed.

 

Congratulations. Always great to hear a success story.

 

Persistance pays off.

 

this very thing happened to a friend of mine yrs ago gets his engine back from a rebuilder puts it in new intake and brand new carb sounds great so far right? he in the drive way which is on a sight incline and he cranking and crusind for like half an hour making ajustments on a carb thats never been run mean while gas is runing down one of the cyinders in back of the engine because of the incline on the driveway. When it finally fired he had a knocking sound coming from the back of the motor. he called the guy that rebuilt the motor and said he had a piston slap. he said he would fix it for free but only if my friend yank the motor,he chose to live with it. morrow of the story? use the old carb that you know that works to brake in the motor