Engine reviving extremely high on ignition

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Sirsmiley9

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My engine is constantly revving extremely high on ignition. I think this may be a result of the fuel pressure being above 7 on my Holley street carb. This pump was supposed to stay below 7 psi but is not. If this sounds like the problem what parts could I find that would cause this so I can get the right parts and fix it
 
It can’t rev if it is not getting a lot of air, can it? Seems like the throttle plates would need to be opening.
 
An engine MUST have air to run. If you cannot throttle it down or kill it with the throttle, You have an air leak someplace. Leak/ cracked manifold, hose disconnected, carb body loose on the throttle plate, bad base gasket, the list goes on and on. You simply have to get busy and check

What brought this on? Is it a new fireup? Did it EVER run right? What changed, etc
 
It was running fine before drove my friend around because the engine swap was recently finished stepped on it at one point and it stayed revving high in neutral nothing purposeful was changed
 
1....First it is not fuel pressure. "Let's say" the throttle blades were perfect for idle speed as before. Increasing fuel pressure to the point that some fuel was forced past the needles/ seats and into the carb would cause loading up, smoking/ smelly idle, and idle speed normally goes DOWN if mixture is too rich

2....I would first try disconnecting throttle cable, take flashlight and look down into carb and see if you can tell for sure if throttles are seated / closed properly. Make certain auto / manual choke linkage is not sticking on "fast idle."

3....Inspect carefully any hoses. You have power brakes? It and PCV hose/ valve are no1 suspects. Try squeezing hose(s) shut with pliers/ vise grips

4....Try wiggling carb by hand see if you can detect any looseness
 
Stick a towel or a rag in the secondaries to block them & start it. See if it idles down. Use something substantial enough that it won’t get sucked in.
 
The problem was unrelated to anything with the carb or vacuum leaks but instead the fact that I have the bracket holding the throttle cable and return springs move backwards slowly which led to the springs not pulling it back enough to set its actual idle to the right spot
 
Return spring?, Carb not closing all the way? KISS principal.
 
Sirsmiley9 said:
The problem was unrelated to anything with the carb or vacuum leaks but instead the fact that I have the bracket holding the throttle cable and return springs move backwards slowly which led to the springs not pulling it back enough to set its actual idle to the right spot
Click to expand...

Refer to item "2", post 13 LOL
 
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