Loud pop

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She'd been sitting in the garage for a few days without being started and when I started her up today I revved it kinda hard to help it start up and I heard a loud pop from under the engine bay. I don't know much about engine internals but if I had to guess I'd say it was piston/rod/cylinder or fuel combustion related but it sounded metallic and I was able to replicate the sound again when revving it past 3,000 rpm's from a cold start. Someone suggested a dry carburetor, Idk jack about carbs, this is my first car with a carburetor. The engine is a rebuilt 351w with 1200 miles on it so it technically hasn't been broken in to my understanding, I always thought you should break it in for 5k miles before you start ragging on it

 

Bully Bob

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IMHO.., don't do that... [-X

Let it warm up on/with the choke a bit.  These aren't race trucks.., there's no need to hammer

the throttle even when warmed up. But especially on start-up.

My guess would be you had a "backfire" .... not uncommon with carbs. (BTW, what carb is that.?)

       -- You should update your info page so we can give correct, current answers --  :-B

Your timing may be sensitive or a tic high & a hard hit with the throttle/accelerator-pump floods the intake

& shoots fire back out the carb.  Not good for the carb either..., especially a Holley.  :( /emoticons/[email protected] 2x" width="20" height="20" />

 

Bully Bob

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Well.., they (holley) don't have to be babied. When properly tuned.., they're GREAT..!!

It will perform/function like any other brand. Supposedly with a bit more HP.

A backfire can knock out the power-valve.

 

Seabronc

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Pay attention to Bob's comment about timing.  That is usually the cause of back fires.

:)>-

 
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Rusty shackleford
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I have a basic elementary understanding of what most parts are and their function, I don't know much about carbs or internal components. But I'm gonna get it checked out this week, it's got all kinda of issues; death wobble, squeaky ball joints, needs timing belt, needs all gaskets replaced, the headers rattle, the doors don't lock, steering wheel is crooked, and it might kinda run hot, engine temp got to around 230 today

And that's just the stuff I know about. It starts up nice and shifts well and has a lot of power and sounds healthy, plus the body, frame, and interior is pretty nice, it just needs some tlc

Should I avoid driving it until I get new suspension, I only drive it locally under 45mph

 

Seabronc

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Steering and suspension would be priority, if the engine runs fairly well then hold other stuff till it is a safe handling vehicle.

:)>-

 
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Rusty shackleford
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Also, I noticed some smoke coming from this area, I don't know if it was the fluid leaking onto the hot header or if it was coming from that wire

 
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Rusty shackleford
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Is there supposed to be that much room on the bolt where this connection is, not sure what part that is, lol is that the tie rod? Sorry I'm still learning

IMG_8170.PNG

 
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Rusty shackleford
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I should also mention that I taught myself how to drive a manual with this rig and the loud carb backfire noise happened during shifting when I'd let off the clutch too soon and give gas too late when shifting from second to third

 

Seabronc

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Backfiring is a timing issue as Bob stated in his first post.  It is caused by a cylinder firing before the intake valve is fully closed and igniting the fuel in the intake manifold.

Pressure in the float chamber, NO.  Even if it did have pressure, the result would be bogging from too much fuel in the intake.

Not possible to tell what you have under the hood except a very pretty engine with a Holly carb.

Smoke most likely from that oil leaking down onto the manifold, as evident from the picture.

:)>-

 

Bully Bob

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"I can hear the carburetor backfire when I shift sometimes, is that user error or mechanical"

Not user.., likely the timing or carb adjustment.  

--- There's no pressure in the carb. Only slight press. when the accelerator pump is activated via the gas pedal.

Eng. looks pretty much stock except for the carb, intake manifold, headers, radiator, & electronic ignition.

That bolted on item is a "pitman arm".  Yes it is on correctly.

The wobble is likely in the steering linkage. If it's worn out.., don't fix it.

Replace with the earlier style "T" design. That "Y" design was OK with a stock suspension but not

with lifts & other mods.

Also, the ball joints come into play, as well as the power steering box.

Bad timing could cause hi temps.

Some headers make a "ticking"  sound.., that's normal. Don't see how they could "rattle".

 
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Rusty shackleford
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"I can hear the carburetor backfire when I shift sometimes, is that user error or mechanical"

Not user.., likely the timing or carb adjustment.  

--- There's no pressure in the carb. Only slight press. when the accelerator pump is activated via the gas pedal.

Eng. looks pretty much stock except for the carb, intake manifold, headers, radiator, & electronic ignition.

That bolted on item is a "pitman arm".  Yes it is on correctly.

The wobble is likely in the steering linkage. If it's worn out.., don't fix it.

Replace with the earlier style "T" design. That "Y" design was OK with a stock suspension but not

with lifts & other mods.

Some headers make a "ticking"  sound.., that's normal. Don't see how they could "rattle".
I just assumed it was the headers, there's some sort of rattle coming off the engine only when it's warming up, I'll def be replacing that y design steering linkage with the T design and get the timing fixed.

 

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