Hey everyone, I’m pretty sure I know the answer to this, but I’m relatively new to working on cars and just trying to learn everything that I can. I am working on a 460 in my 1970 F250 camper special. Obviously not the original motor. As I’m trying to get this thing timed and the carb adjusted, in addition to chasing some sort of a vacuum leak in my carb, when I put the timing light on it it shows like 35° BTDC. I’m thinking that the distributor is set in a tooth off, and I need to pull it out and re-stab it one tooth counterclockwise? Am I thinking about that right? One tooth off changing the timing mark on the balancer by around 30°? Thanks everyone for your help.

 

Did you verify TDC and check zero on the balancer? Are you using a adjustable timing light?

 

hey, yes, I verified TDC on the compression stroke, as far as my balancer is accurate. I just bought a piston stop so I can verify the accuracy of the balancer. And yes I’m using a quality timing light that is adjustable, but I’m only using the initial timing function currently. Haven’t been able to get past this to start working on my mechanical advance and total timing.

 

So if you verified 0TDC and the timing light is set to zero then your assumption about being off a tooth is correct.

 

I know there’s some debate about whether being a tooth off actually causes any kind of issue. For me, I think it just limits the amount of rotation I can get on my distributor, and makes the timing marks inaccurate on the balancer. Does it actually cause issues with running rough? Or could you theoretically just correct that with advancing the timing if there was no limit to how far you could rotate the distributor.

 

It makes no difference and doesn't do anything to the marks on the damper. It just limits your ability to rotate the distributor enough to set timing. With it 35 degrees off it can be fixed as simple as moving the plugs on the cap counterclockwise by one space. This should get you in the range to time the engine and have enough distributor movement.

 

Are you timing it with the vacuum hooked up and is it ported or manifold?

 

I had a vacuum gauge hooked up to manifold

 

ok nice. I’ll give that a try.

 

No, was the carb vacuum hooked up to the distributor?

 

Oh, I see what you’re saying. No, I’ve got a mallory distributor on it right now, no vacuum advance. I plan on changing over to a duraspark soon.

 

Back in the day we ran the Mallory Uni-lite but had to had them set-up for each motor. Now yours sounds like it's set-up for a flat out run and has no ability to advance the curve with RPM gain.
On second thought the plate could be stuck.

 

I’ve pulled the top off, it has a couple springs in there, I assumed I could modify it when I go to recurve it. But, I’m actually trying to get a duraspark with a vacuum advance, so I haven’t messed with it yet.

 

Why not just get a Pertronics distributor and coil and be done.
pertroncs 460 ford | eBay

 

There is spark, so have you tried turning the distributor to adjust it yet? Sorry if I misunderstood your concern about the initial timing, but I didn't see where you actually turned the distributor to change the timing.
With your light you can see if the mechanical advance is still working by watching the marks as you rev the engine above idle to higher rpm. If the timing advances, note how much and at what rpm.

An old damper ring may have spun on the hub when the elastomer deteriorates over time and conditions. A distributor can come out of adjustment. You could be using the wrong spark plug for your testing. Lots of things still to verify possibly.
To the spark plug, are you using the Ford version of #1 cylinder, which is the passenger side front? GM or Dodge folks, or those of other vehicles you may have chosen the wrong plug wire to clamp to. GM's #1 is driver's side front.

As said, a tooth off on the distributor isn't an issue unless you don't have the range of adjustment on your particular setup. But it happens a lot because someone isn't familiar with how to install the distributor by turning the oil pump driveshaft to match the gear tooth location so that the distributor drops in.

Lots of little things to learn as you start your auto mechanic life! Hopefully this is something simple.
If the engine is hot and you can still crank the engine with the starter easily, it might not even be at 35° initial. At some point engines become hard to start and crank very slowly when the spark advance is too high. Not sure where the 460 has it's limits, but if you detect some reluctance of the starter to crank the engine, the timing might be too far advanced.

Good luck!

Paul