[jasonwthompson]

Rail rockers with positive stop studs are non-adjustable, they are a bolt down and go type of thing. How can you adjust the preload on them?

 

[jdub]

Change your spark plugs. Could it be that simple? YES.

 

[dylan81]

Rail rockers with positive stop studs are non-adjustable, they are a bolt down and go type of thing. How can you adjust the preload on them?

My understanding was that hydraulic lifters require some amount of preload but there is no real "adjustment".

 

[dylan81]

Change your spark plugs. Could it be that simple? YES.

Would such a lightly modified engine reaction that differently to the same plugs that were used as stock with electronic ignition?

 

[jdub]

Here's what I know. After a successful initial startup on my new engine it wouldn't even start again. I messed with timing, I changed carbs, I did insanity stuff like checking firing order 100 times, on an engine that ran flawlessly for 30 minutes. I finally changed the sparkplugs and it fired right up. I guess I fouled the plugs on that initial run time. Residual oil from assembly? Blowby from not fully seated rings? Carb too rich? Timing wrong? Could be any if those. But new plugs curred months of insanity. Such a simple thing.

I'm letting you know just incase.

 

[dylan81]

Here's what I know. After a successful initial startup on my new engine it wouldn't even start again. I messed with timing, I changed carbs, I did insanity stuff like checking firing order 100 times, on an engine that ran flawlessly for 30 minutes. I finally changed the sparkplugs and it fired right up. I guess I fouled the plugs on that initial run time. Residual oil from assembly? Blowby from not fully seated rings? Carb too rich? Timing wrong? Could be any if those. But new plugs curred months of insanity. I'm letting you know just incase.

Oh I understand what you're saying. I did replace my plugs from the ones that were used during initial startup. Those were somewhat fouled due to an old carburetor I initially had on the motor.

 

[Woodchuck]

Rail rockers with positive stop studs are non-adjustable, they are a bolt down and go type of thing. How can you adjust the preload on them?

Pre '69 are not positive stop.

 

[Roboto65]

Did you degree your cam on install it would not be the first time I have heard of a cam with the wrong grind making it through the loop.

 

[mike657894]

What do your plugs look like? All your symptoms sound like a lean condition to me. You may need to rejet.

 

[dylan81]

What do your plugs look like? All your symptoms sound like a lean condition to me. You may need to rejet.

This is the last picture of the plug I have on my phone. They were all pretty consistent with this one.

 

[dylan81]

Did you degree your cam on install it would not be the first time I have heard of a cam with the wrong grind making it through the loop.

I did degree the cam to 4* advanced.

 

[mike657894]

I would say that is too clean but would take that cam back to 0 degree before worrying about jetting.

 

[cheapbastard]

I agree sounds too lean in the idle circuit which could be caused by vacuum leak or misadjusted carb. Do you have another carb to try?
You could also start it and spray wd40 at various places on the engine to see if the idle changes.

 

[Woodchuck]

This is the last picture of the plug I have on my phone. They were all pretty consistent with this one.
View attachment 862466

Not enough miles on that plug to tell much of anything...

 

[DIHLON]

I did degree the cam to 4* advanced.

You may want to verify the cam doesn't already have a 4 degree advance ground into it; mine does. So in my case, lining up the dots gives me a 4 degree advance.

 

[dylan81]

I agree sounds too lean in the idle circuit which could be caused by vacuum leak or misadjusted carb. Do you have another carb to try?
You could also start it and spray wd40 at various places on the engine to see if the idle changes.

I have an old 4160 Holley in the garage, it would need a rebuild but I can try it. I've tried spraying WD-40, carb cleaner, and propane gas to search for vacuum leaks.

 

[dylan81]

Not enough miles on that plug to tell much of anything...

I haven't driven it much due to the stalling issue.

 

[dylan81]

You may want to verify the cam doesn't already have a 4 degree advance ground into it; mine does. So in my case, lining up the dots gives me a 4 degree advance.

That's correct, I believe it had 4 degrees advance on that grind, so it's set to crank gear zero.