Engine stalls when accelerator is pressed.
Postmaster
Joined: Mar 2011
Posts: 2,698
Likes: 7
From: Taxachusetts
Holley carbs - if you can turn the mixture screw(s) all the way in and she still runs, the power valve is history. That's straight from the horse's.....mouth = Holley. A blown power valve would cause your plugs to look like they do, a very rich (unburned hydrocarbons) smell and difficult starting - somewhat of a flooded condition.
Your carb takes a 6.5 power valve.
Your carb takes a 6.5 power valve.
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Tuned
Joined: Feb 2016
Posts: 299
Likes: 0
Holley carbs - if you can turn the mixture screw(s) all the way in and she still runs, the power valve is history. That's straight from the horse's.....mouth = Holley. A blown power valve would cause your plugs to look like they do, a very rich (unburned hydrocarbons) smell and difficult starting - somewhat of a flooded condition.
Your carb takes a 6.5 power valve.
Your carb takes a 6.5 power valve.
Postmaster
Joined: Mar 2011
Posts: 2,698
Likes: 7
From: Taxachusetts
A little history on Holley carbs: Back in '92 or '96 Holley decided to use a "blowout protection" valve in their carbs. It's just a little bb sized ball and a spring located in the base of the carb, below the power valve. It's supposed to stop the P/V diaphragm from rupturing when a back fire through the carb happens.
I've found it doesn't always work. I had a little fart through the carb once and the power valve s**t the bed. I drilled it out and never used one again. No problems.
Now to address your question: If the carb sat for awhile the P/V diaphragm could get brittle and crack rendering it useless. A back fire would do it, too...my experience in both cases. The mounting gasket could become gas soaked and leak, could be old and brittle, too.
You might luck out and still be able to re-use the blue bowl gasket on the metering block when changing the P/V.
I've found it doesn't always work. I had a little fart through the carb once and the power valve s**t the bed. I drilled it out and never used one again. No problems.
Now to address your question: If the carb sat for awhile the P/V diaphragm could get brittle and crack rendering it useless. A back fire would do it, too...my experience in both cases. The mounting gasket could become gas soaked and leak, could be old and brittle, too.
You might luck out and still be able to re-use the blue bowl gasket on the metering block when changing the P/V.
Thread Starter
|
Tuned
Joined: Feb 2016
Posts: 299
Likes: 0
A little history on Holley carbs: Back in '92 or '96 Holley decided to use a "blowout protection" valve in their carbs. It's just a little bb sized ball and a spring located in the base of the carb, below the power valve. It's supposed to stop the P/V diaphragm from rupturing when a back fire through the carb happens.
I've found it doesn't always work. I had a little fart through the carb once and the power valve s**t the bed. I drilled it out and never used one again. No problems.
Now to address your question: If the carb sat for awhile the P/V diaphragm could get brittle and crack rendering it useless. A back fire would do it, too...my experience in both cases. The mounting gasket could become gas soaked and leak, could be old and brittle, too.
You might luck out and still be able to re-use the blue bowl gasket on the metering block when changing the P/V.
I've found it doesn't always work. I had a little fart through the carb once and the power valve s**t the bed. I drilled it out and never used one again. No problems.
Now to address your question: If the carb sat for awhile the P/V diaphragm could get brittle and crack rendering it useless. A back fire would do it, too...my experience in both cases. The mounting gasket could become gas soaked and leak, could be old and brittle, too.
You might luck out and still be able to re-use the blue bowl gasket on the metering block when changing the P/V.
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Tuned
Joined: Feb 2016
Posts: 299
Likes: 0
I thought maybe be worn vacuum line. I check tomorrow. Thanks for reply.
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