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hesitation on 302

  • Thread starter Thread starter rc4mike
  • Start date Start date Jun 14, 2009
R

rc4mike

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Oct 10, 2006
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Jun 14, 2009
#1
  • Jun 14, 2009
  • #1
I have a mild 302 in my 65. Eddlebrock 750 carb with mechanical fuel pump. Engine ran fine for 2 years and then noticed hesitation upon hard acceleration and when turning hard to the right...not to the left. Also notice it when driving slowly over speed bumps. Feels like fuel problem. Perhaps fuel sloshing around in the carb?

Mike
 
S

sparky

New Member
Jan 24, 2003
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Jun 15, 2009
#2
  • Jun 15, 2009
  • #2
If you have just a mild 302, then I would think the carb is too big. I run a mild 302 in my 70 & only run an Edelbrock 600 cfm barb, which is more than plenty. JMHO of course.
 
2

2+2GT

10 Year Member
Apr 25, 2009
3,333
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Southeastern Pennsylvania
Jun 15, 2009
#3
  • Jun 15, 2009
  • #3
I have to agree. Although the recent development is your immediate problem. You should see if the float is sticking on one side, or some other internal problem. Meanwhile, look into getting a 60o cfm. I used to drive a 289HP with a 3-2V intake, according to Holley it's 780 cfm, and even on the 289HP that was WAY too much. That 750 is enough to operate your 289 up about 10,500 rpm, assuming it doesn't explode long before it gets there.
 

woodsnake

15 Year Member
Jan 16, 2007
1,352
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Hicksville, NY
Jun 15, 2009
#4
  • Jun 15, 2009
  • #4
To me, it doesn't sound like fuel, it sounds like an ignition issue.
If your only mod is a mld cam, I would agree that the 750 might be a bit much. If you have after market heads, and a lot of other improvements, 750 might be perfect.
Does it run rich at all?
 
R

rc4mike

Member
Oct 10, 2006
142
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Jun 16, 2009
#5
  • Jun 16, 2009
  • #5
well i was wrong, its a 650 carb. Not sure if it runs rich. how can you tell? It used to run fine, so something has changed. I guess i could have a loose wire in ignition system somewhere or the float would make sense. I am running a stock ignition system.

Mike
 

jcode68

Active Member
Jul 15, 2003
892
1
29
Massachussetts
Jun 17, 2009
#6
  • Jun 17, 2009
  • #6
rc4mike said:
well i was wrong, its a 650 carb. Not sure if it runs rich. how can you tell? It used to run fine, so something has changed. I guess i could have a loose wire in ignition system somewhere or the float would make sense. I am running a stock ignition system.

Mike
Click to expand...

You can pull the plugs to see if it is running too rich - they will be black around the tips. Souds to me like an intermittent fuel delivery problem. Like if you had a partially clogged fuel filter. I would start there and check the simple stuff first. If the car sat for a while, you could have trash in the tank, might be a good idea to drain it and have a good look inside. Also make sure your choke is fully opening when reaching full temp as this could cause similar symptom (although not likely the speedbump symptom) If all that checks out, then it could be like 2+2GT said - a sticking float.
 
O

oh9mustang

Banned
Jul 27, 2008
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Jun 17, 2009
#7
  • Jun 17, 2009
  • #7
Mike sounds like it could be a couple things wrong.
You stated that "Engine ran fine for 2 years " This would indicate a Fuel filter problem. Take the fuel exit line off the pump and with something to catch the fuel, turn the key on, You should have a nice strong stream.

Then you said
"upon hard acceleration and when turning hard to the right...not to the left"

This would indicate something wrong with the Float in the carb. If it has been worked on, the float is set to high, If it has not been worked on the float is coming lose inside the carb, either way, take the bowl off and look at the float,
 
R

rc4mike

Member
Oct 10, 2006
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Jun 22, 2009
#8
  • Jun 22, 2009
  • #8
update...

cleaned fuel filter and carb. No more problem! Cool. thanks for the help

Mike
 

jcode68

Active Member
Jul 15, 2003
892
1
29
Massachussetts
Jun 23, 2009
#9
  • Jun 23, 2009
  • #9
Glad to hear it was something simple!
 
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