Bouncing Tach

[ZOSO]

Im not sure on points so maybe someone can answer but do you have a ballast resistor? Is it the correct resistance? You maybe getting too much voltage to the coil. Cause them to prematurely fail.

[airbur]

Nope, no ballast resistor.

[hockeydad4-22]

Or because it was trying to overcome the "bronco lean"...

[airbur]

Oh man....I should have known the sh!t was coming;)

I just installed the new condenser....will fire it up when my boy wakes up from his nap.

[Entourage]

Since Airbur's Bronco is sporting pimped-out paint, he now has 'Gansta Lean'.

[airbur]

Yea yea....I was thinking of installing hydraulics...but only on the rear corner so I could droop it and bounce it.

[airbur]

It didn't help:( Still stumbles badly and tach is all over the place. I'm at a loss.

[Viperwolf1]

Try unplugging the tach. Maybe it's bad and it's affecting your ignition.

[airbur]

Just tried that. Doesn't seem to have affected it. Still stumbling. Checking timing again.

[Viperwolf1]

Just tried that. Doesn't seem to have affected it.

The bouncing probably stopped.

[airbur]

ha......ha.......ha

[airbur]

Oh nice new picture I have! Too bad it's not an animated GIF

[airbur]

THAT is EXACTLY what it looks like!! Nice work Master Admin Man:)

[airbur]

Feel free to leave it there.....will be a constant reminder of what I need to fix:)

[airbur]

Yeah, I agree. So you don't think the tach issue is related to the performance problems I'm having?

[airbur]

It does it anytime....even when parked revving. I'm a novice with a multimeter.....club project!

[cobshane]

I haven't all the way through this post, but with a timing light does the light up seem steady or does fluctuate all weird ? Look closely. Your making sure your adjust your dwell before adjusting timing,right.

[airbur]

I did have some dead plug wires a while ago but got that fixed. That was causing issues with the timing light. I do notice that TDC fluctuates a bit when setting the timing. Seems to jump back and forth then pegs for a while then jumps around again. I don't have a dwell meter but have thought about getting one.

[airbur]

Not sure if related but I'm getting quite a lot of black sooty water out the tail pipes.

[cobshane]

Tail pipe water is normal, but dwell meter isn't needed as long as you set point gap right.
Make sure your tdc when you set point gap i think or when fully open point gap then set. And then set timing.
How old is the distributor? Does the shaft have side play? That will mess things up! Points setup can't have any side play!
Dwell meter! I'm too young to even say that word.

[airbur]

Dizzy is brand new dual point Mallory. I checked the points and they are dead on....I think the measurement is .027. No side play in the shaft.

[cobshane]

Dizzy is brand new dual point Mallory. I checked the points and they are dead on....I think the measurement is .027. No side play in the shaft.

Weird, Im sure cap rotor wires plugs are new as well. Is your coil getting full voltage? Charging voltage! Should be 13.5 volts or over, well under 15 volts as well. Check while running with voltage meter.

[airbur]

I'm an idiot with a meter....what are the connections to make at the coil?

Thanks.

[cobshane]

It's like checking a battery. One terminal is voltage and one ground. If you don't know which is what, it won't matter. It will show voltage negative if you hook up backwards.

[Booger]

Dead plug wires? Did you replace them all? How about looking at the cap and rotor to see if it has any carbon tracks between any terminals. Have you hooked up the timing light to each plug wire to see if the miss is related to one or all? Shine timing light on the fan to see it if is varying any. I still wouldn't rule out the distributor. Check the advance mechanism to make sure it's not hanging up. How old is the timing chain? Could it be that the chain is loose and causing a timing variation?

[airbur]

Wires are new. I will check each with timing light today.

The motor is all original other than plugs, wires, dizzy, coil, air cleaner, rear seal, oil pump, and fuel pump.

Anyone know of a 1996 351w for sale cheap?:)

[cobshane]

Fix it yet. Looks like you need to make it to a tech day.

[airbur]

Not yet. Don't think it is reliable enough to get me to a tech day right now:(

[Rox Crusher]

Fix it yet. Looks like you need to make it to a tech day.

love your new avatar

[airbur]

So today I got a brand new tach....hooked it up using different connection points (other than the coil line)....exact same behavior. Tried different grounds, connected the red directly to the battery and still the same bouncing tach.

I'm really at a loss now. Makes me think the RPMs really are fluctuating that much, but it sure doesn't sound like it. It is worst when accelerating. When it's at idle, it doesn't move much.

Plug wires are all good and I checked each one with the timing light.

Help! :)