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New Panhead Advice Needed

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Old Mar 19, 2014 | 02:19 PM
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Default New Panhead Advice Needed

I just completed my 51 pan, and cranked it up for the first time today.

The motor is new, carb is a S and S super B and the rest is stock. Exhaust is an orginal National cycle shotgun set up from the 60's.

Anyway, had a heck of a time getting it to run.

Ended up taking the carb off and the intake to check for leaks, recheck the timing, and make sure the pushrods are set correctly.

Still couldn't get her to run.

Finally I poured a little gas into the carb and she LEPT to life with a mighty roar and running at god knows how many thousands RPM. Tried to turn down the idle and set the mixture screw. Turned off the enrichener and advanced the timing all the way, and she started to settle down, but was spitting through the carb and still running very fast.

Pipes got red hot and I shut her down.

So, it's running hot, fast, and spitting through carb. Any suggestions?

 
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Old Mar 19, 2014 | 02:24 PM
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Check your jets, hopefully that will be it, an easy fix.
 
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Old Mar 19, 2014 | 02:30 PM
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Great looking bike! A lot of my old iron builds fire up kinda similar, and I always end up going back to ensure the timing is right, NO intake leaks (i built a tester for this where I use air pressure and some soapy water), and finally the air/fuel mixture is right. Spitting out the carb is usually from a lean condition, and the fact that she fired up when you added gas supports that as well. Might also want to check that your throttle cable isn't hanging up somewhere causing an open-throttle condition as you're trying to start her.

To be truthful, I usually run a modern CV carb on my Pans and Shovels for reliability and ease-of-starting. Most purists hate me for it, but then again none of my old bikes are restorations.

Good Luck!
 
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Old Mar 19, 2014 | 03:11 PM
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looking at the pic. looks like a bendix carb. has the accel pump. I thought a s&s B didn't have an accel. pump? make sure the accel. pump is squirting when twisting the throttle.ok looking at the pic. that isn't a bendix carb!I would still check for pump squirt!with it running as low as it will, turn in the mix. screw and see if it will die, or at least drop in rpm. is the idle screw still touching the throttle lever at the lowest idle. too hot of pipes usually means lean or maybe timing
 
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Old Mar 19, 2014 | 06:38 PM
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I set the timing according to the book, with the timing line for number 1 on the right side of the hole. I read where I should probably set the full advance timing with the line the center?

Yes, the carb is an S an S super B with a Super bowl. I have run this set up on many many motorcycles, and am totally hooked on it. It is jetted with a 72 main and 32 mid. 72 may be a little big, but not by much. Seems to me a 70 would be ideal. But it shouldn't have caused it to run away like it did.

I have another carb and will try that tomorrow or the next day. One without the super bowl.

I'm leaning towards timing being totally out of whack, but can't figure out for the life of me what I did wrong. First the memory then the legs.
 
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Old Mar 19, 2014 | 07:29 PM
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you have a major intake leak - the brass intake cone seals are not what they once were peek seals is all we use today - jz
 
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Old Mar 19, 2014 | 07:34 PM
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I set auto advance timer with the line at the far right side and the point cam fully advanced and points just bringing the test light on. then double and triple check @ .22 gap. glad I don't use plumbing intake!
 
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Old Mar 20, 2014 | 05:52 PM
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Originally Posted by johnjzjz
you have a major intake leak - the brass intake cone seals are not what they once were peek seals is all we use today - jz
I have weld in nipples with O rings. I am using the heavy duty clamps. That is what I took apart and rechecked to make sure I had not pinched an O ring. Been there...done that.

I have an S and S intake with a 1 inch spacer. Both are sealed with O rings. And I coated them with silicon as an added precaution.

I'm really stumped on this one. I was going to try another Super B that I have. Unfortunately I'm a little behind now as I noticed the oil pump cover is leaking around the return line nipple. Gonna heli coil that, set up the S and S and try again.

I'll keep you all posted.
All advice, recommendations, suggestions appreciated.

I'm going to retime it also, and try moving the line a little further to the right.
 
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Old Mar 20, 2014 | 09:10 PM
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From: la la land jerzey
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its a big little issue - something was over looked - you did not supply a lot of info making guess on many things a typing thing --

if it has points you dident say - condenser is bad

the choke enrichner i have seen the seat out of wack - two different metals the stainless valve and an alloy seat that is drilled with a casted carb body ?? - and that causes all kinds of tuning issues

make sure the distributor body has a good ground use a test light on the body when running if it lights ( blinks when popping ) the ground is not happening add one to the motor under the bike

the ignition switch has high resistance its coroded ( the cross pin ) and its weak in volts passing through it

its going to be this sort of thing an odd ball when you hit it it will respond normal

edit - super B float has to be almost at flood to pick up the fuel correctly
 

Last edited by johnjzjz; Mar 20, 2014 at 09:13 PM.
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Old Mar 20, 2014 | 10:00 PM
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hey John, does that go for the super E also? i had mine adjusted properly and had some too rich problems, so i readjusted the float a tad lower. seems to be ok but I'm always efin with stuff. always lookin for a little bit more, better. hell it never stops!
 
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