I would rotate dist. by hand and see if you can get it to run good.Sounds like a late timing issue.If you can get it to run good timing by hand or ear then you need to find true tdc.Sounds like your dampener might have slipped.To find TDC you'll have to buy or build a bump tool.

 

The cam part number is SUM-1102. I guess it's a possibility that the damper slipped since it is the original one. I have tried to verify TDC but it is difficult with the motor in the car. Going to try again today to see if the timing mark is correct.

When the car was running the other day, I did try to turn the dist. to make it run better. I could get it to rev up a bit farther by advancing it quite a ways, but I still got the popping and spitting.

 

Get a piston stop from summit or jegs to find TDC on #1. It worked for me.

 

It will take you some time to get the bump tool.... if you agree that the harmonic dampener could have slipped then forget about the timing light. Turn the distributor until it runs ok... your timing mark might indicate 45 degrees advanced or whatever but that's not important....

If that solves the problem order a new dampener

 

Timing is dead on. Damper is o.k. Got it running again and it idels fine and will rev up a bit but still the same problem. I am starting to suspect something other than the timing. I can advance it and retard it both ways about a quarter of a turn and I still get the same symptom. Now, I am assuming it is the original cat converter on this beast. What are the chances that it is somewhat clogged? I was able to start the car just now and run it for a while. It seems when the car gets hot it seems to run a bit better. Even pulled it into the garage under it's own power. Once it cools, I am going to take the cat out and see if it's clogged.

It does seem to be running rich still though too. black gook all over the rear bumper...exhaust makes you want to cry. I have ordered another rebuilt Quad and will get it tomorrow. Someone just shoot me now? Or shoot this car! LOL

 

VERY good ! ... fresh motor & questionable exhaust? who'dve guessed? If you can get away without cat in your locale ... remove or gut the cat.

 

o.k. Took the cat out last night and it was full of crap!!! I mean FULL! Ran it open pipe to back it out of the garage and it ran a little better but still opped and crackled thru the carb. Fired it up today and let it run for a little bit, it will rev up pretty good now that the exhaust is uncorked but I am still getting the opping and crackling and the spitting of fuel up out of the carb. I went today and picked up another rebuilt Quad and am going to swap it out tonight and see if it helps. Other than that, I am truly stumped now.

I would think that if I wiped out a lobe on the cam, the lifter or rocker would be making some noise and the valve train is as quiet as can be.

What about an electrical problem? This car sat for quite some time and I am not clear as to why it stopped running in the first place. I have double checked my connections to the alternator and I have verified that the alt is putting out and the battery is charging but the GEN ligt is on in the dash. Not that that may be related but doesn't this car have a rev limiter built in? The tach is not working and is stuck at about 6 G on the tach. I guess I'm just grasping at flies here but I am at a loss at this point. Anyone have any other ideas?

 

Alright, I went and did it. I tore the motor down and pulled the cam. Cam lobes are all o.k. Even the lifters show no obvious wear. Just a bit of swirling where they were rotating nicely in the lifter bores. Guess that blows that idea out of the water. So now what?!?!?! I am going to reassemble it tomorrow morning and see what happens. I still haven't seen anyone post any other ideas.

Oh, I do want to ask this. On the harmonic balancer...the keyway inside the bore where it mounts to the end of the crank snout. On mine, the key way and the timing mark on the outside almost line up. Is this correct? I tried to find a new stock balancer and compare but no one has one in stock. Maybe someone on here can look at theirs and tell me where in relation the keyway is with the timing mark on the outside? If it is similar to mine, then the outside ring has not moved. If it is different well then.... Thank you for taking the time to look at what you have and respond.

 

I had this problem once, and after tearing down my engine with no results... it was that my HEI was'nt getting a full 12 volts. And although the engine would crank up and run fine, it would'nt rev well at all. You could run a 12 gauge wire to your HEI straight from your battery and see if it runs any better.

 

You could have watched the rockers to see if lobes were wore bad enough to cause a problem.
Did you keep the lifters in order,matched to the same lobe they came from ?
What year is this car,motor,intake does it have an EGR valve?
How long has the fuel (or water and fuel)in the tank been sitting ?

 

I tested the lead to the distrib and it is getting a steady 12 volts. Also tested the wire lead from the cap to the inside of the distrib and it was a steady 12 volts as well.

The motor is the original 350 in a 77 vette. HEI ignition, original iron intake, an EGR valve (which is new), and the tank was drained cleaned and filled with fresh gas. I thought about the possibility of hooking the wrong vacuum port to the EGR so I just plugged evert port off and I still get the same problem. I put the lifters back in their original configuration. I haven't gotten it back together yet but will this morning.

I did look at the rockers when it was together the first time and they all moved fine, but if just the top of a lobe was wiped , the rocker would still move and would come off the ramp early and close the valve too soon, possibly causing the problem I am having. But since that is not the case at this point, I am really at a loss.

I will reassemble this morning and run a straight wire from the battery to the distrib just for the shiznit. I gotta tell ya, I've built more small blocks than I can count on my fingers and toes and I have never run into a problem like this before...not even to make myself doubt my engine building skills enough to tear it down and inspect internal parts. I'll have to add a new chapter in my book on this one. Thanks everyone for you input! Keep'em coming!!

 

O.k. Reassembled and ran a direct lead from the battery to the distrib. Still no joy. Actually, now I can't get the car to start. I did notice though, I pulled number 2 spark plug and grounded it against the head. Had my father-in-law crank the car and the spark is inconsistent!!! It is not sparking like it should. Bad ignition module? I have a brand new distrib in this thing too!! AUGH!!!

 

It does happen. Also ... NEVER permit the Bat+ terminal at cap to short across to the Tach terminal ... it'll fry a module/pickup coil ... easy to do when connecting as B & T terminals in such close proximity.

 

Jackson,

Yeah, I learned that the hard way years ago. Never cross those 2 plugs. I am going to advance (auto parts) right now. They say they have a tool to test the ignition module.

 

Ignition module tested out fine, but check this out!!

O.k. this makes no sense. I am out in the garage right now trying to trouble shoot. I took number 1 plug out and grounded it against the exhaust manifold. Crank it and no spark. While I was reaching to crank it again, I pulled the plug off of the manifold and cranked the car...Sparked like a demon!!! When I hold the plug away from manifold by about an inch, it will spark every time just like it should!! It will jump that 1 inch gap and spark perfectly. As soon as I touch it back to the manifold, it stops sparking. Tried to ground it to different things on the car and would not spark, but hold it away and it will jump the gap!!! So, something is grounding out in the car, but what?!?!?!

 

Regardless if new ... maybe the plugs have internal closed short. If so, those sorts of problems tend to exist across a whole production lot / run. Try a new set, different brand, nothing fancy.

 

If you were running rich you may have carbon tracks across the insulator from the plug tip to the threads. This would cause it to ground out.
Are you sure the float in the carb is ok? These carbs were notorious for absorbing fuel and then flooding the bowl. That caused sputtering and fuel spitting out.

 

I pulled all the plugs late last night and tested them all.. They were all bad!!!! And these were brand spankin new ones!! I had an old set lying around and tested those..they were all good, and put them in.. Too late to fire it up with an open exhaust. I think my neighbor would have been a little upset. I'll give it another wack tonight.

The carb is brand new...well reman new, and I took it aprat to make sure everything was tight and that all the parts were in the right place. So, going to hope and pray that tonight proves fruitfull.

 

Patiently waiting to hear your status... did you figure it out yet?

 

O.k. Got it running last night!!! WOOOOOOO!!!!

Now, how? Good question. I tore down the distrib (reman one) and checked evertything, cleaned everything, made sure all the wires were good, routed properly. Reset static timing. Took a coil off my buds car and put that in. (Thanks to my friend for taking the chance that I wouldn't fry his coil and he not get home!!!) I also crawled up under the dash and checked every wire. It looked like someone had totally bubba'd and cobbed the wiring up under this thing!! Also, water had been leaking down thru the dash for some time and wetting everything including the fuse block. I took every wire and rerouted them in a more organized fashion and cleaned the fuse block as best I could. I didn't want to take it apart or mess with it too much for fear that it would disintegrate!! I'll be making a call to Painless soon to replace. So, with that..it fired right up!!! Revved up like a champ!! But now, I'm not sure what the solid fix was!!! So until I find it..I will agonize over it!

Oh, after I got it running, I put my old (new) coil back in and it ran like a champ still, so not the coil. I still have that pesky GEN light on, but the alt is putting out and the battery is charging!!

Thank you everyone for your input..I'll post a solid fix hopefully before I am 60!