Timing not changing w/ rpms

[RustyBuckets]

Im back again to ask for help. I appreciate ya'll.
I had to relocate my temp sensor because it was in the way of the vacuum thing on the dist.
So i loosened the dizzy and turned it. Relocated the temp sensor and turned the dizzy back to where it was and read the timing on the engine and it seemed way off.
I took the dizzy cap and rotor off then made sure the expanding weights were moving easily and they were.
Now the engine fires up well and revs well but the timing reading is way off.
At first it read on the damper where there arent even timing marks. Now at idle i can turn the dizzy and change timing but rpm doesnt move the timing at all.

 

[1987 GMC Jimmy]

Im back again to ask for help. I appreciate ya'll.
I had to relocate my temp sensor because it was in the way of the vacuum thing on the dist.
So i loosened the dizzy and turned it. Relocated the temp sensor and turned the dizzy back to where it was and read the timing on the engine and it seemed way off.
I took the dizzy cap and rotor off then made sure the expanding weights were moving easily and they were.
Now the engine fires up well and revs well but the timing reading is way off.
At first it read on the damper where there arent even timing marks. Now at idle i can turn the dizzy and change timing but rpm doesnt move the timing at all.

Marginal adjustments make a difference in setting the timing. Are you saying that once you broke out the timing light, you were able to get the base timing set properly? And are you also saying that you can't make the timing advance with an increase in RPM's while the vacuum advance is connected? If I understood correctly, it sounds like you might need to check out the vacuum advance canister. The diaphragm may have failed, and it's just leaking vacuum and not doing anything.

 

[RustyBuckets]

yes ive tried with the vacuum adv connected and with the vacuum plugged. Turning the dizzy changes timing but increasing rpm does nothing. How does one inspect the diaphragm?

 

[HotRodPC]

If the timing isn't changing at all, then you've got 2 failures. 1 the Vac advance isn't advancing timing, and #2 the centrifical weights are not advancing the timing. I have a feeling the plate in the bottom of the dizzy is seized and not turning.

 

[74 Shortbed]

Sounds like the plate isn't moving..

 

[Honky Kong jr]

Set it where it runs the best, starts well and lock it down. I don't use any advancement methods. Weights are gone the plates are drilled and tapped to keep them in place and vacuum advance not hooked up. Watch for detonation though higher octane fixes that though.

 

[HotRodPC]

Set it where it runs the best, starts well and lock it down. I don't use any advancement methods. Weights are gone the plates are drilled and tapped to keep them in place and vacuum advance not hooked up. Watch for detonation though higher octane fixes that though.

You're kidding right???

You're cheating yourself out of performance and mpg bigtime. That's just not good advice IMO, but to each their own.

In this case if it were me, I'd either be taking the dizzy out and rebuilding it or buying one of the cheap Skip White China dizzies off of eBay cuz if he's getting no advance at all, as said, there's at least 2 functions not happening. No mechanical advance and no vac advance. Something is hung, rusted, stuck or just flat wore out in this dizzy and it needs to be taken apart and thoroughly checked out, cleaned and lubed. If you're going to do all that, may as well put new bushings etc in it, so cheap out on the time and labor, and just get the new one for $50.

oops, looks like they've gone up in price. Used to be $49.99 FREE Shipping. Now they're $47.95 + $10. Still not bad considering they come with everything, module, cap and rotor. Cheap but effective. http://www.ebay.com/itm/SBC-BBC-CHE...1-R-/332040852906?vxp=mtr&hash=item4d4f2d55aa

 

[74 Shortbed]

Locked out is for racing not the street..

 

[HotRodPC]

Right, set it at 32 degrees full advance or even more in somce cases and lock it down, but that's not advisable at all for a street rig. A race rig is usually idling at 1500rpm or more too, not 600-800.

 

[Honky Kong jr]

Sorry I usually don't daily what I build and my latest build runs on 106 or better still contemplating E85....which likes timing. Also I do believe I said what I do not what OP should do.

 

[HotRodPC]

You must have lotso cash cuz running 106 is high doller gas and it can't be getting but about 5 or 6 mpg if it needs 106. E85 isn't expensive but the mpg is even lower yet but very doable to make a daily driver street/strip ride. Probably a better idea there. Quick Fuel makes some affordable E-85 ready carbs, then it's all about the plumbing from the tank and fuel pump being E-85 compliant.

 

[Honky Kong jr]

You must have lotso cash cuz running 106 is high doller gas and it can't be getting but about 5 or 6 mpg if it needs 106. E85 isn't expensive but the mpg is even lower yet but very doable to make a daily driver street/strip ride. Probably a better idea there. Quick Fuel makes some affordable E-85 ready carbs, then it's all about the plumbing from the tank and fuel pump being E-85 compliant.

I wish I did. I was mixing 50/50 with 93. I know all about the mileage whoas of E85. My company truck is flexfuel and where I usually get 11-13mpg on weasel piss I was getting around 8 on E85. Nice thing is every 3 months I will run a tank full of corn juice threw to do a fuel system cleaning. They clean what the others leave behind.

 

[Honky Kong jr]

Sorry for the typo I "don't" usually daily my toys.

 

[RustyBuckets]

I turned the dizzy to as close as i could remember it being originally. Started it and drove it around the block. Drove better than before i changed anything. No detonation or weird running problems. I rebuilt the dizzy about a year ago. Replaced cap, wires, and rotor. Not sure which plate ya'll are talking about.

 

[1987 GMC Jimmy]

There's gotta be a way to test this. Shouldn't you be able to suck on the hose and see if the plate moves? If it doesn't, and you can feel air being sucked through, then the diaphragm in the canister probably broke, and it needs to be replaced. It sounds logical, but I don't deal much with vacuum advance.