Over the winter I put in a new cam(comp XE262),timing chain, lifters, starter, headers, ignition wires, and ported the 416 heads on my LG4. Finally got everything back together and now the car won't start. It cranks but never starts. There's an occasional puff of smoke and a pop out of the carb or the headers(where the smoke comes from depends on the position of the dist.). I checked the wires for spark, all checked out fine. I'm going to replace the plugs tomorrow, but I don't think it's that because they only have ~100 miles on them.

From searching the boards all I could find is that the dist could be 180 off. I don't think so since when I put it in I watched the valves on the #1 cyl with the valve covers off, they were both closed all the way until I got the timing pointer lined up. And I had already double checked TDC on the balancer with a piston stop. I put the distributor in with the rotor pointing at where the #1 terminal should be, clamped it, put the cap on, connected the wiring.

I've double checked the wire routing/firing order and that's all ok. Still not starting.

Only other info I can tell you is that when the starter is turning the engine over, the tach is reading about 250. The battery voltage was reading a little low too, so I put it back on the charger.

Any other ideas I can try when I start the car again?

-Matt

 

not sure how to check TDC on the balancer with a piston stop, but anyway try moving the distributor a little and it wouldn't hurt to have someone else check the timing since it's easy to repete your own mistakes and not catch them. you do have spark right? you have the valves adjusted right? not too tight?

 

Thanks for the reply.

Well, as far as checking TDC with a piston stop, I just made sure the valves on #1 were closed until the piston hit the stop, and the timing mark was at 0 on the pointer. Probably not the best way, but was all i could come up with.

I did move the distributor around and like I said, all it really changed is where the smoke would come from, exhaust or intake.

I'll go recheck the valves again and make sure they are not too tight.

 

Well, I adjusted the valves and it started up. Thanks ede.

But it won't idle. I'm guessing it's a carb adjustment problem. Idle speed screw?

Thanks a lot.

-Matt

 

I just had the exact same problem with my 69 chevy truck.

I installed an edelbrock intake and carb.Along with a comp cams 270h cam,lifters and timing set.


it did exactly what you are talking about.I could get it to run.Only way advanced though.

I know you don't want to hear this.I had my cam 180 degree's out.


I had to tear it back down and redo it all.Fired right up and runs alot harder than it used to.

 

How can a cam be 180 off? The crank should be in the exact same position for every 1/2 rotation of the cam, right? Maybe I'm just not seeing it...anyone want to elaborate on this?

 

The dist is 180° off.

Use #1 compression, and then the next #1 TDC immediately floowing it, as your indication of where the engine is turned to; I'd bet you have the spark going to #6 when #1 is at TDC right after it has been having compression.

 

But it actually runs, sounds pretty good too, until it dies. I just have to stay on the gas or it sputters and dies. It also dies if I put it in gear and let the clutch grab to try and move it.

I'll recheck the distributor but I had already made sure the rotor was pointing to the #1 terminal at the top of the #1 compression stroke(watched the rockers with the valve covers off until piston came all the way up, they were both closed)

Another thing is that the idle will fluctuate between 700-1000 then the car starts shaking, idle drops to ~500 and engine dies.

-Matt

 

pull the dizzy and turn the rotor 180...you are out....TDC occurs twice on #1....for #1 firing and #6 firing

 

That is exactly what my truck was doing.


I am not sure exactly how.(I am just a stupid 17 year old kid)My truck had the exact same symptons.


It would run and idle.But as soon as you put it under a load.(trying to move the car)It would die.If you tried to give it gas it would spit and sputter like crazy.

I am thinking it has something to do with the difference between ignition timing and valve timing.If you don't have them right.it isn't going to run.

 

I flipped the dist 180, wouldn't even start. Rotated it both directions...wouldn't start. It would pop smoke out the carb here and there. So I put it back the other way and it starts but doesn't idle for very long unless i stay on the gas, but even then it eventually dies.

I dripped water on the headers and all of the primaries burn the water off except 1 and 4, they get warm but not hot like the other 6, so looks like i'm only running on 6 cylinders. I'll readjust the valves on those cylinders and recheck that spark is getting to them, but it just started raining so it'll have to wait.

Aside from valve adjustment and ignition, is there anything else that would cause a cylinder not to fire when others are firing?

-Matt

 

if you have any question about the valve adjustment you just made run a quick compression test on the cylinder after you adjust the valves...if they are adjusted wrong it will show on the guage...of course you need to do all the cylinders to get a baseline....

 

I think I figured out how you can install a cam 180 out.


The cam opens and closes the valves right.The cam also has the gear on the end that turns the distrubitor.The gear on the end of the cam is made to the way that the lobes are placed on the cam.Meaning that if you take the cam and install it 180.It will be opening the valves or closing them whenever they need to be closed.Because of the plug firing,compression,etc,etc.

Does this make any since?