New Small Block Stroker Engine Noise

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If I put each lobe on its base circle and push on the rocker they don't move. The lifters are pumping up. At this point I don't think its a lifter problem. The roller tips on the rockers are no where near rolling off the valve stem so I know its not that. I am going to take another look at the torque converter bolts next. A friend of mine is going to lend me a mechanics stethoscope so hopefully that will help find the noise. It does sound like its in the torque converter area, passenger's side, around the oil filter. If you listen to the video you can hear its loudest in that area.
 
Have you listened to it with a timing light on it? If it goes in time with the light its at 1/2 engine speed which means its in the top end. If it goes at 2x the light, its at engine speed and its in the bottom end.

Just trying to throw out some diagnostic help..... We all are at wits end until we can ALL stand next to your car and figure it out! I hope this gets figured out soon!
 
redfastback said:
Have you listened to it with a timing light on it? If it goes in time with the light its at 1/2 engine speed which means its in the top end. If it goes at 2x the light, its at engine speed and its in the bottom end.

Just trying to throw out some diagnostic help..... We all are at wits end until we can ALL stand next to your car and figure it out! I hope this gets figured out soon!
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Thats a good suggestion to use the timing light. I feel frustrated at times; that is when I walk away from the car and let it sit. The noise will be found; I'll keep looking until I find the source, even if it means pulling the engine back out.
 
red, you know I've never heard fo that... cool idea.
340, I cant see the video on this PC. I'll have to check back tonight.
 
340sFastback said:
If I put each lobe on its base circle and push on the rocker they don't move. The lifters are pumping up. At this point I don't think its a lifter problem. The roller tips on the rockers are no where near rolling off the valve stem so I know its not that. I am going to take another look at the torque converter bolts next. A friend of mine is going to lend me a mechanics stethoscope so hopefully that will help find the noise. It does sound like its in the torque converter area, passenger's side, around the oil filter. If you listen to the video you can hear its loudest in that area.
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Oh ok.. I thought you ruled out the torque converter, etc... because you ran it before.. yeah... that might be what it is for sure now that you mention it. It did get real loud when you went underneath the car.

Excellent suggestion Steve!
 
I just ran it for about 30 minutes listening with a Mechanics Stethoscope for noise. The fuel pump is very quiet, alternator just whirls around, the distributor makes no noise, some noise inside timing chain cover, intake manifold between runners completely quiet both sides, there is noise coming out of the valve covers but it sounds completely consistent no matter where you put the end of the stethoscope; no area is louder then another. Both sides sound the same. On driver's side I can even put the stethoscope probe right through the breather hole on the baffle; no different sound then the outside of the valve cover.

Loose hood hinges are NOT making noise (hood is not on). Transmission lines are not rattling. Headers have lots of clearance around everything.

Probed all around the oil pan, including where the crank scraper is. There is noise in the oil pan but it all sounds completely consistent front to back, side to side, except around the oil pump pick up, you can hear the oil getting sucked in.

There is definitely a racket on the torque converter dust cover and the lower bell housing. There shouldn't be. I could get the probe on one area of the upper bell housing from the top and no noise there.

With the front of the car high on jack stands running it is clearly louder under the car then on the top no doubt about it.

I let me 15 year old son take a shot at listening all around with the stethoscope to get second opinion. He sees it the same way I do. And he didn't get burned by the headers or stick his hand in the fan so thats good.

I'll be pulling the torque converter cover tomorrow night.
 
I remember years ago,a friend installed his engine and when he started it made all kinds of noise underneath.It was the pump in the tranny.He wasn,t happy.I,m not saying this is your problem,just something you could check off your list of things that could go wrong.Hope ya figure it out before Santa shows up with his helpful elves.No pun intended,just a haha!!
 
Make sure the convertor bolts are not hitting the block too...

It sounds to me like a valve train noise stilll... But follow the stethascope...
 
moper said:
Make sure the convertor bolts are not hitting the block too...

It sounds to me like a valve train noise stilll... But follow the stethascope...
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Moper thanks for looking at the video.

I agree it does sound like valves still. I would think if it were valves there would be a difference in noise across the valve covers? There is noise, clacking, coming from the valve covers that you can hear with the stethoscope. But it does not vary, its the same every where you put the probe, even on the baffle through the breather hole, it always sounds the same. Both sides, front to back, always sounds the same. I would think there would be a difference in the sound if it were the valves? And its definitely louder under the car with it jacked up, no doubt about that.

What worries me is I REALLY paid attention to those torque converter bolts because when the old 340 was rebuilt in 1981 the torque converter bolts hit the dust cover and made a big racket. I vividly remember the grief looking for that noise so I was real careful with those torque converter bolts. I know they are tight and I know the torque converter was fully seated when the engine/trans were bolted together. The engine/trans mated together easily, did not need to tighten bolts to draw them together. And torque converter turned easily once all bolts were tight. I did pull the converter out and replace the font seal and had trouble getting converter to seat. But I never forced it in. I moved the gear selector around and thunk it seated all the way in, 1/2" farther in then the face of the bell housing. So if a noise is there why?? And all those parts were just running quietly on the old 340, so how could they be making this much noise (assuming that is the problem) on this engine??
 
look on backside of dust cover to make sure nothing is rubbing on cover itself, or try running it without cover at all
 
mod38-1 said:
look on backside of dust cover to make sure nothing is rubbing on cover itself, or try running it without cover at all
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I did take the cover off after the engine was first run because of the noise. I saw no signs of it hitting the bolts and it still made the noise with the cover off. I did watch the converter spin with engine running and didn't notice anything strange. But I did not look the bolts over closely, just looked at the dust cover, saw it wasn't hitting the cover, so I moved on. I had to bend it very slightly to get it off because headers were in the way. Then when I found header leaks I thought the problem was found so I straightened the dust cover and put it back on when the headers were off. And like I said, the bends were very minor on the out side edge, the cover is not all mangled up or anything like that.

Since then I did pull one spark plug boot off at a time with engine running and noise did not change so that says the header leaks are now fixed.
 
It does not sound good what ever it is. With a piston to wall clearance of .0045" I would not think pistons would be slapping around.
 
We've been over allot so forgive me if I say something that has allready been discussed but since you said it's loud down below in the oil pan area also could it be the crank making contact with the windage tray (assuming your running one)? Or maybe the crank making contact with the oil pump pickup? When you assembled the engine did you make sure everything on the rotating assy. cleared everything real good? The oil pickup wouldn't be too close to the oil pan floor would it? I've seen them rattle if they are.
 
fishy68 said:
We've been over allot so forgive me if I say something that has allready been discussed but since you said it's loud down below in the oil pan area also could it be the crank making contact with the windage tray (assuming your running one)? Or maybe the crank making contact with the oil pump pickup? When you assembled the engine did you make sure everything on the rotating assy. cleared everything real good? The oil pickup wouldn't be too close to the oil pan floor would it? I've seen them rattle if they are.
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Fishy, all good suggestions.

Oil pick up is around 1/8"-1/4" away from bottom of the pan. I mocked it up with no pistons or crank installed and reached down through the cylinder bore and felt how far away from the pan it was. The oil pick up tube is fastened to the #3 main stud with a nut. I cleaned the nut and stud with break parts cleaner and fresh paper towels then put a good amount of loc tight on that nut and its on there tight. That oil pick up is not moving. When moving the stethoscope around the oil pan you hear noise but no area is louder then another. I could actually hear the oil getting sucked into the pick up that is how good the stethoscope works. No windage tray is installed. Kevko oil pan has a build in crank scraper but when I put Stethoscope on the pan right where the scraper is no noise at all.

The Scat I-beam rods are at least 1/4" away from the oil pick up tube. Rods were something like 1/8" away from hitting block, tons of clearance. Piston skirts were not close to hitting crank throws at the bottom of their stroke either.

I need to look inside that torque converter area and see if I see signed of contact on any of the bolts.
 
That's a great idea of how to make sure the oil pickup is positioned right. I'll have to remember that one.

Sounds like you got a good stethoscope too. What brand is it? I need to get one and if you can here it sucking oil up over the sound of the engine it must be a good one.
 
Just a thought. I had a cracked flex plate one time. Noise started out only when under stress/hard acceleration. Finally got to where it sounded like a rod/main bearing. By then, the entire center of the plate had separated.
 
340sFastback said:
No windage tray is being used. I also removed the torque converter dust cover to rule that out. Years ago my 340 had the torque converter bolts whacking the dust cover because the oil pan gasket was not in straight. And that noise made it sound like a rod was knocking, it was loud.

I do think the crank is smacking the oil dip stick because its bent and I know if was not bent prior to starting the engine. So I am going to run it with the dip stick out while diagnosing this noise.
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This was your response on the second page of this thread when I asked if a rod or the crank was hitting the windage tray. As stated, you're not running one, but i just noticed in your response to Fishy that the pan does have a built in scraper.

This in conjuction with the bent dipstick bothers me immensely. I'm willing to bet that there is some sort of oil pan interference.

BTW, great idea redfastback in regards to using the timing light to diagnose engine noise!
 
I am diagnosing the problem with the dip stick out. I put the stethoscope on the oil pan right where the crank scraper is and there is no noise so it is definitely not that.
 
fishy68 said:
Sounds like you got a good stethoscope too. What brand is it? I need to get one and if you can here it sucking oil up over the sound of the engine it must be a good one.
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A friend lent it to me and I don't know what brand it is. But he did give it to with the original plastic case which has some name on it. I'll post up what it is when I get home.
 
I'd be removing the intake and pass side valve cover at this point. It sounds like a lifter not even trying to pump up. You can also try pulling the cover alone, and manually working each rocker individually. If I had to guess, I'd say either #4 or #6 is the issue.
 
moper said:
I'd be removing the intake and pass side valve cover at this point. It sounds like a lifter not even trying to pump up. You can also try pulling the cover alone, and manually working each rocker individually. If I had to guess, I'd say either #4 or #6 is the issue.
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That's what I said in post #100... 340s answer:

"If I put each lobe on its base circle and push on the rocker they don't move. The lifters are pumping up. At this point I don't think its a lifter problem. The roller tips on the rockers are no where near rolling off the valve stem so I know its not that. I am going to take another look at the torque converter bolts next. A friend of mine is going to lend me a mechanics stethoscope so hopefully that will help find the noise. It does sound like its in the torque converter area, passenger's side, around the oil filter. If you listen to the video you can hear its loudest in that area."

Not trying to mock you or anything 340 but it seems now it could be both or one of the two. I would run that sucker with the valve covers off and at idle take a piece of wood and press on the rockers as they move. When the noise goes away (if it does) then you have found the offending rocker.
 
Took torque converter cover off, bolts do not look like they hit anything. I took all spark plugs out, put tape on the converter bolt heads, and turned by hand. Tape did not get scraped. Had my son hold a putty knife between block and crank and those bolts did not hit or move the putty knife so those are not hitting. Flex plate to converter bolts look like they are 1/8" away from the block. Put starter back on and ran engine with tape still on the converter bolts (dust cover off). Shut engine down and bumped it around and tape was still in tact on the converter bolts and not scraped. Noise still sounds like its in the torque converter area or its bouncing down that passenger's side header? Exhaust valve smacking piston and echoing down the header maybe or exhaust valve smacking shut and noise bouncing down the header? Is the trans pump making the noise? Torque converter does not look like it wobbles and its not leaking. Summit has chrome valve cover for SB mopar for $21, get some and cut the tops off and run like that?? Stop working on cars and find another hobby? I am trying to upload a video but you tube is slow.
 
moper said:
I'd be removing the intake and pass side valve cover at this point. It sounds like a lifter not even trying to pump up. You can also try pulling the cover alone, and manually working each rocker individually. If I had to guess, I'd say either #4 or #6 is the issue.
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Moper, I am going to do what you suggest. Do I need to run the engine first and check them before they bleed down? Its tough to tell the cadence with a timing light but if I had to guess I'd say its with the timing light, not twice as fast. Could an exhaust valve be smacking shut and the noise is bouncing down the header tube and that is why the noise is under the car? Or maybe the lifter plunger gets collapsed and then sends the shock up the push rod, transmits it to the rocker, then to the valve, and then the noise travels down the header tube?
 
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