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[C2] Started running like crap

Old 07-14-2018, 10:44 AM
  #21  
CorvetteMikeB
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Originally Posted by prestige6 View Post
Went to Cruise night last night. Took the 67 427-435 ran great going there. Was about 25 miles away.. Coming home was running great . Came to a detour when I slowed down, would night idle. Had to keep playing with the gas to keep it running to make it home.. Any ideas where to start. Thanks


Could it be Vapor Lock???
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Old 07-14-2018, 01:16 PM
  #22  
prestige6
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Originally Posted by CorvetteMikeB View Post
Could it be Vapor Lock???
I'm going to put 1/4 inch plates between the carbs and manifold.
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Old 07-14-2018, 03:58 PM
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Originally Posted by prestige6 View Post
I'm going to put 1/4 inch plates between the carbs and manifold.

That is suppose to lower the fuel temperature in the carburetor reservoir I read somewhere.
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Old 07-16-2018, 08:15 PM
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Originally Posted by CorvetteMikeB View Post
That is suppose to lower the fuel temperature in the carburetor reservoir I read somewhere.
How can I tell if a power valve is bad??
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Old 08-10-2018, 05:19 PM
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I was talking with Phil at custom carbs . He told me to put the spacers in the carbs which I did. He also said it could be the fuel pump. When running at highway speeds the carb is working fine. As soon as you come to an idle the pump could be producing more than 7 lbs. causing it to load up. That's why I want to install a fuel pump gauge and regulator.
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Old 08-10-2018, 06:23 PM
  #26  
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You can measure the fuel pressure basically with a $13 vacuum gauge/fuel pump pressure tester and have your answer in 8-10 minutes -- no reason for a permanent gauge and re-plumbing your fuel lines... You prob have more pressure at cruise with the pump diaphragm cycling faster....

There is a ton of tri-power info at the bottom of this web page and it might be interesting to read through it:

http://www.thecarburetorshop.com/Troubleshooting.htm
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Old 08-10-2018, 08:40 PM
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There is such little fuel consumption at idle speed that is where a mechanical fuel pump will make it's highest pressure. Every turn of the camshaft resets the diaphragm high against the spring where max pressure would be and the diaphragm moves very little because of the low fuel demand.

The secondary carburetors have idle circuits and the gaskets where the metering plates screw to the main body can leak causing a rich condition if that's what you are questioning.
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