A bad cam/dizzy gear could cause the bearing to go, which could cause the rotor to break. It has to be something like that given the rotor breaking.

 

Just an idea...

 

Thanks for all the great ideas. I am planning on digging into the timing and distr. this coming sunday with my dad. Gonna check all that and pull the spark plugs and give them a good bath in carb cleaner and a wire brush. Heck they were just $1.50 autolites so I might as well just get all new spark plugs. Either way the timing will be checked and distributor will be pulled and set to factory specs, I just found my chiltons manual today. I will update you all on Sunday night on what the results are. Thanks again for everyone's help and advice!!

 

One last question...are you from a Chevrolet backgound? I only ask because of a problem we had years ago with too many hands on an engine. Or only GM fan was tasked with changing the plug wires. The car ran horribly afterwards (69 Mach 1, 390 4spd)...none of us could figure it out. Called my father to take a look...he sees it for maybe a minute, looks at our friend and says "you wired it like a Chevy", danged if he didn't. GM's cross count the cylinders (one bank is 1,3,5,7 other one is 2,4,6,8) where Ford calls them down the side (1,2,3,4 and 5,6,7,8).

Make sure you put the wires on counter-clockwise.

Kenny

 

Ok so here is what I have found after doing much fiddling with the timing. I went out and got me a fairly inexpensive timing light but not the cheapest. First thing I did was check the timing at idle and I did make sure the engine got warmed up and idled smooth, around 650-700 rpm at idle. The initial timing I found was at 6 degrees ATC. That is right I said ATC, no mistake there. Right away I readjusted that to 8 degrees BTC like my manual says. I went off of Chiltons and also the Factory Service Manual. And I did double check the firing order and it is definitely 1,3,7,2,6,5,4,8 (NOT 1,5,4,2,6,3,7,8)

Now I went to check the advance timing, I hit the throttle up to around 3k RPM maybe more and it does advance which at that RPM was just beyond the 30 degree mark on the damper where the factory timing marks are. I thought well that must be ok because the service manual makes no mention of what the advance timing should be or maybe I missed reading it in there, so I took it out and the same "no power" issue is still there. So I went back and double check my timing at idle and advance and the second check of the advance timing I notice something weird.

Even if I just hit the throttle to maybe 1k RPM the advance jumps to that 30 degrees or more. I pulled off the vacuum tube to the distributor and with that off the timing stays at 8 degrees right where I set it no matter how much throttle I give it. So I dug into the distributor to check the springs and weights, because even with no vac the timing should advance somewhat with the weights right?

I did pull the distributor apart to look at the weights and they look ok, nothing out of the ordinary it seems like. The distributor was never actually removed from the engine though. I am at the conclusion that the exaggerated advance is what is killing my acceleration power. What should I look for with those weights or with the vac advance? Or should I just bite the bullet and buy a new distributor and call it a day?

 

You say it was running good before, that you didn't change the dizzy and that now that you've re-timed it you have no power...

Like Anafiel said, is TDC #1 really TDC #1???
Are you sure the damper hasn't slipped?

Can you advance the rotor forward and back with your hand?
Does it wobble side to side at all, in any direction?
Maybe the little chunk of rotor contact got wedged in/under the advance plate.
I don't understand how you could disassemble the dizzy without removing it.

30* total doesn't sound exaggerated, it doesn't sound like enough...to me at least.
Would depend on the cam and the advance curve.

Vacuum advance should drop as the throttle is opened, not increase.
It makes sense for it to go full (vacuum) advance right off idle if you're using ported vacuum as a source.
And now you've proved the vacuum advance is -indeed- working.

Lose the Cat and see if you get your power back.
What kind of two barrel carb, and is it clean?
With ethanol in the gas it can only take a week to gunk things up.

 

I am about 99 percent sure I got to TDC on #1, I pulled the number one spark plug and did the thumb trick. If the damper did slip which is possible I think, are there alignment marks for when they are replaced to ensure that the timing marks are in the proper alignment?

The distributor is the original Motorcraft as is the carb, model 2150 on the carb. And no it is not clean at all. I was able to get to the weights of the distributor by way of taking the stator out, two screws under the cap hold the stator down and the weights are right underneath. I have a heck of a time removing the reluctor as I noticed some rust had it stuck in place pretty good. there does not seem to be any side to side wobble in shaft, very solid.

I know my power issue lies somewhere in the distributor. It just has to at this point. I did also notice that when it does advance timing up to 30 or more it stays there. I hold the throttle steady at say 2k RPM the advance does not move at all from 30 degrees. As you said it should come back down as throttle remains steady right? To me it sounds like something is not right with the advance, either in the vac or weights.

Last night I did a vac leak check using the propane trick and did not find any leaks. If I did have to replace the Distributor what brand should I go with? OE, Proform, Cardone, MSD, or Mallory? which one should I stay away from too?

 

No, that's not the way vacuum advance works. If you are using ported vacuum you won't have vacuum, nor advance, at idle. As you crack the throttle open the port will be exposed to vacuum so the advance will come in. And, since the engine will continue to produce loads of vacuum when not under a load the advance will stay. But, if you put they engine under load the vacuum and the advance will drop.

My advance gives 22 degrees of advance at full vacuum, which is about what you are saying you have: 8 degrees of initial advance plus 22 degrees of vacuum advance equals 30 degrees total - not including the mechanical advance you should also have.

 

Gary,
I said"right off idle"
With ported vacuum there should be no advance at idle, but the most advance just as the throttle butterfly passes the port and tapering off from there as the throttle opens under load.

I don't know why, but it seems that NOCO has no mechanical advance at all.
...Or it is full against the stops at idle.

I'm still trying to understand how the timing got retarded to after TDC if he didn't touch the dizzy.
Cam chain skip a tooth or two???

 

Oh, got it. Yes, maybe it skipped a tooth. Or, maybe we have a cam/dizzy gear problem? We still haven't accounted for the rotor being broken, and something caused that shaft to move.

 

The mechanical advance should be where the weights come into play right? I am really leaning towards just getting a reman Distributor to throw in there.

If it did jump a tooth or something like that I should be able to pull it and see some sort of wear on the drive gear right? There is no abnormal sounds coming from the engine and the new rotor has not broken like the last one.

Im really stuck at which way I should go....

Continue digging at the OEM distributor?

or

Pick up a reman for 65 bucks and go from there?

 

I hate throwing parts at my truck hoping to fix it.

Do you have any service history?

I would definitely say that if your timing set is thirty two years old it's past time for a new one. (and this would give you an opportunity to have a look at everything else)

 

You know, there is some very good wisdom there.

With all the questions floating around about this issue, I'd say pull the timing gear cover and have a look-see. Heck, go ahead and buy a new timing set, and replace the three decades old set. Timing chains stretch/wear, and can cause an erratic ignition event. It'll also give you a chance to do a good inspection.

If you go this route, let us know if the old gear marks lined up? Be interesting to know if you jumped a tooth or not.

 

Im gonna go ahead and do the new distributor, and timing chain. I have no service history on it and I doubt I could find any. The guy I got it from was an old farmer in eastern CO. Probably did all his own work on it in a barn. Which is no biggy for an oldy like this truck. I will tear her down and get to the guts of the timing chain and cam gear for the "dizzy". Might as well through in a new alternator, from the looks of it, that appears OEM too.

I will definitely post the results for everyone, might take a few weeks but I will not leave ya'll in suspense on this. Thanks again for all the great advice, I really learned a lot from everyone.

 

Hey, I resemble that statement! What's wrong with working on 'em in a barn??

(just kidding...)