Carburetor Noise

-
J

Joe1020

Member
Joined
Oct 2, 2016
Messages
10
Reaction score
3
Location
Los Angeles
Thanks for your input. This issue started recently and it finally today hit the wall. It is a 1965 Dodge Dart with a 273 LA/4Bbl Carter afb. The car has no low end torque and shakes from a start, it does still move with that constant sound. Water temp is solid, oil pressure is good.

If you could please take a look at the video and tell me whats going on, what the fix is?

Thank you.
 
Either the spark plug wires are not in the correct order, or there is a valve/cam issue.

That my take on how well you can tell from a video on the internet anyway.
 
Could be a lot of things, broke valve spring, rocker backed off, exhaust push rod fell off, jumped time, cap rotor plugs points, check the dist, compression test, then pull valve covers,?
 
Last edited:
Definitely sounds carb related, for a half second it sounded like a rattle/grind but as 340demon suggested a good place to start.

Jake
 
Almost sounds like the accelerator pump isn't working.


Here is a free warning......all the accelerator pumps on these AFB's are not the same. I had one that the pump was going bad in a few days. Turns out it is a different accelerated pump.


Go to carburetor-parts.com and get the number off your carb and find the correct parts.
 
Valve train problem! GM 305's and 350's sounded like that back in the day when the cams went flat!
 
I'm with TB,
crossed wires, or bad wires.
or a bad plug,Or a plug insulator with a wee-tiny almost-can't-see-it crack.

But; If you have been turning up the idle, to keep it running, then i might guess a faulty intake or a maybe, a flatted cam, but I lean more to a valve adjustment or a bad intake valve, or two
 
Last edited:
Ive seen that before when one side of the carb was plugged. As in left or right side, not front to back.
Is that a dual plane manifold?
If it is it would be two inside cylinders on one bank and two outside cylinders on the other bank that are fueled by half of the carburetor.
You could probably tell if this is the problem by pulling spark plug wires off to see which cylinders are not firing.
 
Last edited:
Mopower71 said:
Ive seen that before when one side of the carb was plugged. As in left or right side, not front to back.
Is that a dual plane manifold?
If it is it would be two inside cylinders on one bank and two outside cylinders on the other bank that are fueled by half of the carburetor.
You could probably tell if this is the problem by pulling spark plug wires off to see which cylinders are not firing.
Click to expand...
Can't be with a stock Hp273 intake. It's a open plenum intake.
 
toolmanmike said:
Can't be with a stock Hp273 intake. It's a open plenum intake.
Click to expand...
That's what I thought, Toolman, but learned otherwise. I had a needle hang open against the jet on one side on a stock open plenum manifold. The right side plugs were all fouled, the left bank's were dry. AJ and the forum helped me thru that one.
 
toolmanmike said:
Valve train problem! GM 305's and 350's sounded like that back in the day when the cams went flat!
Click to expand...
bought a 350 chevy acted just like that after boys dad put plugs wires cap an buttun on it,...5 and 7 plug wires were crossed,...swapped them then carryed the boys car back to him,..he keept the money anyway...lest i was straight with him...

had a 86 monteSS with 305 thay were werst for bad cams,...went to poping threw carb when it started going bad....
 
The car ran great for a couple hundred miles after I replaced the motor heads. There was a ticking sound from the motor, gradually got worse. Replaced the exhaust header gaskets, checked for leaks, loosened and re-tightened the exhaust coupler.

Checked the rockers, engine running with valve covers off, no knocking. My lash settings are definitely off. Took it to a carb shop, older knowledgeable owner said it doesn't sound like the carb. More like a small vacuum leak.

Took it to the exhaust shop, they checked patched a small leak near the back of the exhaust. They tightened the coupler.

On the drive home it just bogged down, horribly. My thought was FINALLY! Now I get to see what it was. I am taking it into a shop. My thoughts are bent push rods, carburetor or ignition. This one is a little above my knowledge...

Edit: I never changed the order of the plugs, or even moved them.

Thank you for your replies.
 
It's got a dead cyl for sure, maybe 2 popping back through the intake and very ruff and shaking when accelerating, It has a major valve train issue. Serious misfire. valve train for sure, check the rockers, push rods, springs.
 
That engine has a wiped exhaust lobe on the camshaft. Sorry, but that's what it is.
 
Fixed an old 307 sb chevy quite a while back that did the same thing. Sounded like a machine gun outta the carb when the throttle was opened. AsRusty & yellow rose said Iit had a wiped out exhaust cam lobe. $20 says you have the same issue man. New cam & lifters and that 307 ran great! For a sb chevy that is!
 
You must log in or register to reply here.
-

Back
Top