318 funky response and noise

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74 dart sport

Kameron
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Recently, my father and I got our 318 running and the car driving. We got it back from the exhaust shop yesterday. We then took it out to test out the kick down cable and how it was shifting. But then, the engine started making two funny noises. One is a clicking sound ( likely a stuck lifter , since the sound speeds up as the rpm increases). The second noise is what worries us. The second noise is a very low pitched banging/ clicking noise. When the car starts up, it sounds like this: ( let . Represent 1 of these noises) .. . ... .. ... . ... . And so on. When we turn the ignition off, it goes like ... And then the noise stops. Here are some other things we noticed:
The engine seems to get hotter than it should

When driving , the transmission seems to grab the gears very lazily. There is a shift kit in the tranny, but it sure doesn't feel like it (tranny fluid is full). It seems to be slipping gears almost, although it did get better with adjusting the kickdown ( we might just need to find the sweet spot for the kick down

The deep pitched noise is accompanied with a vibration

The exhaust sounds funky to my dad, while I think it is just the cam noise

When cruising at ~20 mph, the response is lazy when tapping ( depressing 80% for a second or two) the accelerator.

The 4 barrel on the car now is pretty old , probably going to be replaced since it seems to be working poorly.

We are hoping the noise isn't a bent rod ... Any thoughts on any of these problems ? Thanks , Kameron
 
As far as the kickdown linkage that does need to be just right. I know when I had to made a bracket for my wife 66 Barracuda when we put a 4 Barrel on it it was just one little turn of the thread that made the difference between bang gears and slipping gears.
 
Could be a bent pushrod and/or stuck valve. You can check them by removing the valve covers and rotating them by hand (you'll have the rotate the engine by hand a little at a time to be able to spin all of the pushrods). It will be obvious if one's bent. If none are bent, then you'll need to dig deeper, and if one is bent, there's a good chance it has a stuck lifter, so you'll still need to dig deeper.
 
I would get a mechanics stethoscope and pinpoint the noise. If you have a lift, that would help. Don't panic because some noises like loose torque converter bolts sound like knocking rod bearings, but can be tightened easily with minimal disassembly. Knocking rod bearing would do it at idle and can be isolated by pulling spark plug wires (this lowers combustion pressure because of no explosion in the cylinder). A ticking lifter will eventually get quiet after all the air is bled unless it is defective. Did you have the engine or trans out?
 
74 dart sport said:
How about the deep sounding noise ? Not the clicking one?
Click to expand...

Hard to tell without hearing it. If it's a bent pushrod, and it's bent enough, it could be hitting the sides of the pushrod tunnel, and would make a different sound than the ticking, but should be in unison with the ticking
 
I just re-read your post, and if there's a banging, it could be a bolt is slightly backed out of the torque converter or flexplate and is hitting some thing. Hard to tell, could be lots of things, but I'm all about checking the easy stuff first before needlessly tearing something apart.
 
Yes they have headers. We originally had the engine and the tranny out , they are both not stock. We have a mechanics stethoscope and it is likely the pushrod making the clicking (I guess there is an oil additive to unstick the lifter / rod. And I really hope it is the plate making the noise. It would make sense if it was, since we only put two bolts (not even the right length) on it so we could quickly get it on the street. Thanks so much and sorry for the late reply, I am running at my high school track meet right now
 
It is not uncommon for the exhaust to bang around and hit the body. Since you have a new exhaust, that is certainly a possibility. If there are hard hangers (no rubber insulation) then the banging will be really bad. I'd start there.

Can you take a video and post it with the noise?
 
When I started it up. There was no banging this time . I think it is the exhaust , since if a rod was bent , it would always make that noise. The exhaust is hung by metal. With a piece of rubber at the top where it contacts the body. I think the exhaust was moving around when driving, and that's why it made the noise
 
I've had my exhaust touching my body and it made a rattling noise like from taking it off and putting it back on not just quite right.
I edited my first post on post #2 you DO have to set the kick down correct it IS very sensitive
 
74 dart sport said:
Yes they have headers. We originally had the engine and the tranny out , they are both not stock. We have a mechanics stethoscope and it is likely the pushrod making the clicking (I guess there is an oil additive to unstick the lifter / rod. And I really hope it is the plate making the noise. It would make sense if it was, since we only put two bolts (not even the right length) on it so we could quickly get it on the street. Thanks so much and sorry for the late reply, I am running at my high school track meet right now
Click to expand...

Ok. The reason I asked about the headers is because after I thought about it for a while, I remembered having a similar noise with my 318 after I put headers on (Doug's). It turned out to be the exhaust (seems like the collector flange) was just close enough to cross member to tap against it when it was running. It was a sound similar to what you're describing, and had me worried too. I can't remember what I did to remedy it; I might have left it like that until I put in the stroker.
 
74 dart sport said:
When I started it up. There was no banging this time . I think it is the exhaust , since if a rod was bent , it would always make that noise. The exhaust is hung by metal. With a piece of rubber at the top where it contacts the body. I think the exhaust was moving around when driving, and that's why it made the noise
Click to expand...
There you go. If the rubber at the top is a small square block in a thin steel wrap that is bolted to the body, they seem to be getting popular but suck for isolation of engine movement and vibration from the body. My son and I are taking them out and putting in old fashioned rubber hanging straps to get rid of all the noise from the exhaust system that is banging/moving the body panels.

Car sounds good!
 
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