Author Topic: Hesitation when taking off  (Read 7204 times)

Offline Kavesh

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Re: Hesitation when taking off
« Reply #45 on: March 29, 2021, 12:35:34 AM »
The voltage at the battery while idling at 13.9v, confirming a good charge from the alternator.

I have bypassed the resistor wire when I installed the HEI a few years ago.

I am assuming you mean with the engine running to get the same voltage at the BAT terminal as recorded across the battery?

I need to figure out a safe way to do this test.

I am hoping to borrow a fuel pressure regulator to test whether my fuel pressure is good enough for the quadrajet. If I recall between 5-7psi would be ok.

I will report back soon.

Offline tayto

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Re: Hesitation when taking off
« Reply #46 on: March 29, 2021, 12:07:12 PM »
you want to see battery voltage @ the red 12v plug at the distributor. ideally the same as what you are reading at the BAT terminal. ie: 13.8Vdc,not 13.5 or 12.9,etc. if readings are identical this means there is no voltage drop which is what you want. if readings are not the same this means you could have a bad connection, undersized wire, resistor wire, bad distribution, etc

Offline Kavesh

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Re: Hesitation when taking off
« Reply #47 on: April 01, 2021, 01:52:25 AM »
Hey guys, just an update

I found a possible issue on the intake. When the motor was apart for overhaul, I decided it was a good time to relocate the carb return spring to the rear of the intake. Mine originally was located at the front of the intake. During the drilling and tapping I made a hole through the intake. When I assembled the motor I used thread tape on the bolt into the hole to seal.
I removed the bolt and noticed the area slightly oily, perhaps a small vacuum leak here. I put thread tape again and the erratic idle seemed to have gone away.
I have now used RTV on the bolt threads to try make a better seal after removing the thread tape.
I still have both carbs and will test over the weekend to see whether there is a marked improvement.

Any better suggestions for a better seal on the bolt hole?

Offline Cliff Ruggles

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Re: Hesitation when taking off
« Reply #48 on: April 13, 2021, 04:40:22 AM »
Use a stud instead of a bolt and coat it with Marine Tex or a very high grade epoxy......

Offline Kavesh

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Re: Hesitation when taking off
« Reply #49 on: April 14, 2021, 10:10:40 AM »
Thanks Cliff, thats a brilliant idea :)

Offline Kavesh

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Re: Hesitation when taking off
« Reply #50 on: April 27, 2021, 07:11:06 AM »
Just to close this off now, I have used a bolt as Cliff suggested with some high grade epoxy.

So far so good 8)

Thank you to everyone that contributed to this thread. I would not have been able to do it without the advise given here.