Am I screwed? Loud knocking

[super-bee_ski]

Yup, exhaust leak,,

 

[Michael_]

Sounds like an exhaust leak

I agree. It does definitely not sound like a knock to me.

I had the same problem and used a smoke machine like used in nightclubs to diagnose the problem.
Just shoot the fog into your exhaust tips on the back of the car and see where it comes out on the way to the engine.

You can use something like this: Z-3000II Fog Machine - Antari Lighting And Effects (Or also the cheaper Z-1500II)
This generates a lot of smoke so you will be easily able to tell where it comes out.

 

[icetech]

Best war movie ever made.. By miles.

Great vid of the sound. My pop used a long screw driver to his ear for internal diagnostics. Also, would partially block the exhaust tip with a rag to increase the source of the leak upstream.

View attachment 1393855

 

[Daniel Toro]

If not an exhaust leak check that nothing is hitting your torque converter cover, like a torque converter bolt. But doesn’t sound quite metallic enough for that so exhaust leak is most likely. If you have exhaust manifold gaskets I’ve seen entire pieces of them break loose and get blown out a few times.

Thank you. No cover in there, tried to put one but the bolts were hitting it straight away, not a chance.

I agree. It does definitely not sound like a knock to me.

I had the same problem and used a smoke machine like used in nightclubs to diagnose the problem.
Just shoot the fog into your exhaust tips on the back of the car and see where it comes out on the way to the engine.

You can use something like this: Z-3000II Fog Machine - Antari Lighting And Effects (Or also the cheaper Z-1500II)
This generates a lot of smoke so you will be easily able to tell where it comes out.

That is a bloody good and simple idea.

 

[metaldad]

Best war movie ever made.. By miles.

whats the movie?

 

[Fran Blacker]

If your under the car get a picture of your torque convertor bolts. They shouldn't hit inspection plate, you may have the wrong type head to thick.

 

[Hollis P. Wood]

whats the movie?

Das Boot: I’d call it the best one of the sub flics.

 

[dspur]

Back in the early mid 70's I had an A12 Super Bee. Had hooker headers on it then, but they developed leaks all the time, those things were spot welded many times. Sounded exactly like your video. Scared the crap out of me the first time, then it became almost routine. Those 440 six pack engines are pretty darn tough, very unlikely to be an internal issue.

 

[icetech]

whats the movie?

Das Boot as stated above.. it's in german and 1/4 way in you won't even need the dialog.. it's done so well you can smell the inside of that boat, even sat through the 5+ hour directors cut.. was amazing (it was first made as a mini-series then re-cut into a long movie)... ok.. back to exhaust leaks now

 

[Speedbird]

I've got the director's cut. It was done with no CGI.
Cool how they used a miniature and had to get the wave action correct on screen.
Darned smart, those Germans.
Unfortunately, a video always sounds "tinny" as opposed to the real sound.
But, yes on here it does sound like a click and not a knock.
Woody and Tinny Words

 

[66Satellite47]

I'm surprised as heck. My initial reaction was it's an exhaust leak. I'm shocked that so many of our contributors had the same reaction.

 

[cosgig]

Change those flange gaskets between the manifold and pipe while you’re down there. They seem to blow out far too often, and I always have a couple sets on hand for that very reason.

 

[QuickBpBp]

Had leaks with headers years ago.. How I stopped it was soaking the white paper like gaskets in water. Then install the headers warm the engine up and tighten the bolts again.. When you needed to remove the header typically it tore the gasket in 1/2 leaving it stuck to the head and the other on the header.. No leaks..

 

[Mick56]

A way that I have found exhaust leaks is to squirt some diesel into an engine at fast idle. It will make a ton of smoke, and should show where any leaks are.

 

[Rob Jett]

On the pessimist side of the equation, my '68 RT is sitting in the garage sans engine and it was making almost the exact same noise.
With a stethoscope I could tell it was something internal vs. what I had really hoped was going to be an exhaust leak. I pulled off the oil filter, cut it open and found a bunch of brass looking glitter all throughout. Thrown rod bearing.

 

[Fran Blacker]

Are you running a bronze dist drive gear? Dist bushing. Ya doesn't look good but........

 

[Archie Duiker]

Sounds like an exhaust manifold leak to me. Have had a few of those over the years. Are you manifolds bolted on tight? Exhaust pipe bolts tight?

 

[64BEL]

A way that I have found exhaust leaks is to squirt some diesel into an engine at fast idle. It will make a ton of smoke, and should show where any leaks are.

ATF produces the same result, too.

 

[chtampa]

I agree. It does definitely not sound like a knock to me.

I had the same problem and used a smoke machine like used in nightclubs to diagnose the problem.
Just shoot the fog into your exhaust tips on the back of the car and see where it comes out on the way to the engine.

You can use something like this: Z-3000II Fog Machine - Antari Lighting And Effects (Or also the cheaper Z-1500II)
This generates a lot of smoke so you will be easily able to tell where it comes out.

Simpler is a smoke bomb from a fireworks supplier. We used them to find leaks in sewer vents in walls inside of houses.

 

[BlooDSMeaR]

Check your tq converter. My car made the exact same noise. So we went to pull the motor, and all 4 tq cover bolts were loose. Tightened them up, started it up noise was gone. I still pulled the motor and built a 512 for her.