I have a 351C that I put a new dizzy in.I then used a vacuum gauge to set the timing,had 15 in of steady vacuum.It was running fine,started fine, turned over easily.Beautiful,so just for kicks I use a timing light just to see how much advance I had,over 50degrees of advance at idle.All kinds of nasty thinks should be happening with that much advance,right?
I have started over ,took out and reinstalled the dizzy at least a half dozen times with the same results.The only thing I can think of is that the outer ring on the damper spun.what could be some other reasons for showing that much advance.

 

What is your inital at idle? don't think this is to far out. Kinda common with openchambered heads. If your fuel don't ping should be good. Just did a truck with about 45 degree's and 15" vacume. inital was around 18 degrees if I remember correctly. its kinda scary but the thing is make sure it don't ping the fuel or detonate engine.

 

50degrees at 795 rpms inital.No ping

 

I have 2 questions........

1) Are you checking timing with the vacuum advance hooked up ?

2) Have you verified that when #1 piston is at tdc the pointer lines up on zero on the balancer ?

Is it possible your timing chain jumped time ? I've run across that before. If your chain jumped, a lot of times you have to crank it way advanced for it to start and run decently. Mags300

 

definetly need to look at dampner for sure. Is their any vibration in engine. Or does dampner wobble while running. Might be some timeing chain wear also? machineing back in the day wasn't so good and might be a keyway alignment to dampner issue. interesting but as far as running if engine doesn't ping the fuel or detonate it'll run.

 

It shakes a little, but it does have a hotter cam so that could be the cause of some of the shaking.
The thing turns over so good,it does not act like its working against itself and it doesn't even make a complete revolution before it running.
New timing chain and gears. I guess I'll get a new damper.

 

What about the vacuum advance ?

What happens when you set the initial where it's supposed to be ? (12-16)

 

Vacuum advance is unhooked and plugged.It runs like crap and when I try to floor it it will spit back thru the carb and die

 

Let me know what you find with the damper.

 

If the dampner isn't wobbling. the rubber isn't being pushed out? Everything looks good as far as dampner, wouldn't change. Definelty need to inspect and make sure you keyway is good. If all OK I would just make your own timing mark on dampner. Use a tape measure to reference off of other marks and should be good to go. open chamber heads usually require more timing. need to make sure you have the proper dampner on engine. will look into part numbers and see what I can find for you. My ford book says their are 3 different types, 2v and 4v engine. make sure you get a tape measure and measure your diameter. Sometimes they might give you the wrong dampner like a 351 windsor or 351m. The M is similar to 351 cleveland because of the counter weight built into dampner. need a ford number off dampner to confirm correct dampner. good luck and lookin through books to get a number as we speak. hopefully have this number?

 

All 335 series dampners will work.There are timing marks on the outer faces of the dampner,see if they are still in alignment.And as Wyoming said,look for any physical damage to the rubber press fit areas.Look at the keyway area in the hub and on the crank snout.Dampner is nothing more than a balanced rotational shock absorber.Something is whacked with your overall timing though.That is way to much overall.

 

Is it possible for the outer ring to move about a 1/4 turn when running and to return to the right place when the motor is turned off?
The rubber is cracked and bulging.

 

If the rubber is bulging between the rings,it is time for replacement.I wouldn't think the rings would move back into position with the engine stopped.Once they slip it is all over.

 

Have you tried putting #1 piston at a perfect tdc and check where the timing marks on the damper are compared to the timing pointer to see if it is off ?

 

Not perfect tdc but close.close enough to pick it up in the dizzy.Ordered a new damper from Jegs.The old one is off and the rubber is in bad shape but the outer ring seems tight.