Rpms rapidly increase at startup

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Kllrbee

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Jul 3, 2018
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Location
Richmond IL
6 bbl holley.
Startup immediately at 1500 rpms then keeps climbing quickly. Finally cut it at 4k.
Tried to WOT to reset fast cam lever...nothing. Kept increasing.
Something binding?
All I did beforehand was remove/reinstall secondary springs to see which ones they were and manually forced linkage forward to check how dirty underside of outboard plates are.
What caused this rapid and continuous increase in rpms?

Any more info u need, let me know.
 
Which one is stuck wide open?or did one become disconnected from the linkage and vacuum pulling it open?
 
Throttle assembly and return spring/s on?
Off the top it sounds like throttle plates opening without user input or a HUGE vacuum leak.

Aint a lot of info there to go on.
 
Yeah, it does seem like throttle opening, but the secondaries arent stuck open. I disconnected the linkage and closed them manually....still happens.
Would have to be a pretty huge leak....what the heck is up here? Very strange.
 
It has to be a throttle valve, cuz in order to hit 4000, there has to be fuel in that air. If it was dry air it would either peak or slow or stall/run very rough.

Post #1 says 6bbl Holley; is that right?
 
I still had the vacuum hooked up to the secondaries...unplugged those and all good.
So the other day I checked to see what springs were in there. (Car is new to me). Plain springs.
I must have put them back in wrong cuz this wasnt happening before.
Theres only one way for them to go in, cant see how I could have messed that up...lol.
At 900 pm, when my car is screaming at 4k rpm in my garage and my neighbors start calling, I admit I felt some anxiety.
 
One time I had the weights in the distributor stick open, wide, and the car started and then gained rpm. new springs cured it up, just my thoughts, Good Luck
 
Could the Carb be leaning out do this men ?
 
I bet you have the secondaries vacuum line on the wrong nipple on the center carb. One goes to the vacuum advance on the distributor and the other one goes to the front and rear carbs.
 
They were wrong. Had dist right, but had pulloff on other one up top and secondaries on the base plate...not good. No wonder they opened at idle. That one should be where the pulloff goes right?
Still weird that they werent opening at idle before I checked the springs. Could they have been binding and when I checked them, it freed them?
 
They were wrong. Had dist right, but had pulloff on other one up top and secondaries on the base plate...not good. No wonder they opened at idle. That one should be where the pulloff goes right?
Still weird that they werent opening at idle before I checked the springs. Could they have been binding and when I checked them, it freed them?
 
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