Top end popping noise

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Dustert73

Dustert73

Stripping bolts since ‘10
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Hey guys, the 360 magnum in the duster has been running pretty strong the last few months. But this Saturday I was cruising along and the engine started to tap/rattle/light knock, like a valvetrain type noise more than rod knock. It was running super rough and was surging while I was trying to limp it home. I got home and pulled off the valve covers and ran it, I didn't notice anything abnormal going on and it was getting plenty of oil. I never had a loss in oil pressure, always stayed above 15-20 psi at idle and at least 40-50 while driving.

I have the front torn off the engine and the intake off. While I was turning the engine over with a ratchet there's a popping noise coming from the lifter valley/valvespring area. It sounds like a hot exhaust popping/pinging after you turn the car off. The car hasn't ran since yesterday so the exhaust or engine is cold. I tried loosening up the rockers in pairs to try to isolate the noise, but it seems like it keeps moving around. I have a video of the noise if it would help.

What's going on here? Is there a valve spring broke, or a few of the lifters bad? I can't see any obvious damage to any valve springs
 
Could be needle bearings breaking up in the lifter rollers kind of like a driveline makes popping sounds when the needles break up in pieces.
Could that be the sound and why it seems to move around?
Only way to check is pull them and inspect for loose rollers.

Also inspect the rockers and make sure a rod or two isn't trying to go through them. (If you have stamped rockers)
 
Holy **** a valvespring broke! I'm pretty sure the cam is too much for the springs. They are stock eq head springs and the cam is a pretty much comp xe 268 copy regrind. Should I be worried about the others? I'm definitely suspect of them even though the rest look fine. Rockers look fine, the lifters roll just fine, the spark plugs are a few months old tops.

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Good work! Broken springs can show up with a variety of symptoms. I've heard one that did not ever pop or ping; the cylinder was just weakish.

If my thinking is right, the EQ head lift limit as shipped is .525" (Someone please stop me if I am wrong!) An XE268HR cam is .535" lift with just the 1.5 rockers, but I am not sure from the vague cam description what actual lift you have. If that is correct, then yeah, you are pushing things. Even a non-roller XE268 type profile pushes around .500" of lift.

Springs can break individually..... so it could just be a random weak part. But the fact that there is no damper can be setting up some harmonic vibrations inside those single springs and that will certainly stress the springs a LOT.
 
Thanks for the help guys, It is a huge relief finding the problem! I found the cam card, intake is .492 exhaust is .501 with a 1.5 rocker. So if my math is correct intake is .524 exhaust is .534 with a 1.6 rocker. From memory I remember seeing the eq head springs being good for .510 . It's dumb I thought I could get away with it for the summer, and I didn't.

I went to pick n pull today and pulled a stock magnum truck cam with the 50% off sale. It's unfortunate but I'm thinking about swapping in the stock cam to take the stress off the valvetrain. I can't afford Hughes springs which I think would be the fix to this.
 
Dustert73 said:
Holy **** a valvespring broke! I'm pretty sure the cam is too much for the springs. They are stock eq head springs and the cam is a pretty much comp xe 268 copy regrind. Should I be worried about the others? I'm definitely suspect of them even though the rest look fine. Rockers look fine, the lifters roll just fine, the spark plugs are a few months old tops.

View attachment 1715052280
Click to expand...

A whole new set of springs costs less than a dropped valve - replace all springs with new ones...
 
Dustert73 said:
Thanks for the help guys, It is a huge relief finding the problem! I found the cam card, intake is .492 exhaust is .501 with a 1.5 rocker. So if my math is correct intake is .524 exhaust is .534 with a 1.6 rocker. From memory I remember seeing the eq head springs being good for .510 . It's dumb I thought I could get away with it for the summer, and I didn't.

I went to pick n pull today and pulled a stock magnum truck cam with the 50% off sale. It's unfortunate but I'm thinking about swapping in the stock cam to take the stress off the valvetrain. I can't afford Hughes springs which I think would be the fix to this.
Click to expand...

Have your head guy verify that there is clearance to run that much lift and so you won't bind the springs at that lift......
 
If you did get to coil bind, then you had better be checking rockers, fulcrums, fulcrum bolts, keepers, and retainers on all cylinders. Of course, you can just turn it over and watch for a valve to open to the max and see how much coil clearance is left..... My first guess is just too much energy into the stock spring.

Comp 994-16's (single spring + damper) are dead ringers to Hughes 1100's and cost a bit over $100 for a set from many sources. They would give you almost .100" coil bind clearance. I am not sure if they would work with your retainers though, and if the damper would clear the seal. The dimensions are here in this chart:
COMP Cams® - Valve Springs By Design

2 questions:
- Where is that pick n' pull near you?
- Why does the spring next to the broken one in the pix look different?
 
That's one thing I checked during during assembly of this engine is the clearance between coils and retainer to guide clearance. Can't remember how much i had seen with the feeler gauge for the springs but they weren't touching.

Those comp springs might work. Only difference I can see is the installed height, the Hughes 1110 springs are 1.66 and the comps are 1.55, could that cause problems? Pretty sure I'd be changing retainers with those springs like the Hughes 1110's. For whatever reason I thought the Hughes springs were more than what they are, the retainers are kinda spendy, which I might go to the junkyard and pick up some 2.2 retainers which I seen on here would work. I'm probably going to end up keeping the cam in the engine and getting all new springs.

That pick in pull is in Columbus Ohio. The springs are all the same, they look all the same in person. They've got some overspray on them.
 
I am not sure where you're getting the 1.55 installed height for the 994-16 springs. They list a 'Seat Load' of 102 lbs at 1.700" installed height and installing at 1.650" (standard SBM installed height) would give a seated valve load of 120 lbs, which is right there with the Hughes 1100's. Again, I don't know if your retainers, seals, and springs seats will work with either spring.

Yes, you 're gonna have to solve the spring thing sooner or later. I can't recall if Summit or Jegs is close enough to you, but getting a single 994 spring might be a good way to check it out. Summit lists them for $6. Clever on the 2.2 retainers... I did not know that.

Hmmm, I used to go to a good pick 'n pull down near the Olentangy River south of OSU in Columbus. I wonder is that is the same place.
 
nm9stheham said:
I am not sure where you're getting the 1.55 installed height for the 994-16 springs. They list a 'Seat Load' of 102 lbs at 1.700" installed height and installing at 1.650" (standard SBM installed height) would give a seated valve load of 120 lbs, which is right there with the Hughes 1100's. Again, I don't know if your retainers, seals, and springs seats will work with either spring.

Yes, you 're gonna have to solve the spring thing sooner or later. I can't recall if Summit or Jegs is close enough to you, but getting a single 994 spring might be a good way to check it out. Summit lists them for $6. Clever on the 2.2 retainers... I did not know that.

Hmmm, I used to go to a good pick 'n pull down near the Olentangy River south of OSU in Columbus. I wonder is that is the same place.
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Yep, the 2.2 retainers give more retainer to guide clearance and is what Hughes sells for the EQ and Magnum heads for using a 1.6 rocker and is good to close to .600 lift.
I am running them with the Hughes 1110 springs with dampers at about .520 with the 1.6 rockers.
Installed height and bind clearance wasn't a problem with the 1110 springs (110 or so on the seat) IIRC.
 
I got that measurement from jegs. Jegs is closer than summit to me, and Yeah that's the same pick n pull, I normally at least look what's in the yard during the 50% off sales. I got a pair of older looking bucket seats out of a 80's dodge van in that yard during this sale for 35 bucks. Then all this happens during the first drive with them in lol.

The 2.2 retainers are the same as the 2.5 retainers right? The part numbers are the same on rock auto. There's only one car in pick n pull with a 2.2 which would leave me 8 retainers short. but there's another car with a 2.5

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OK, well you CAN install them at 1.550" and get the Jegs listed 153 lb seat pressures, but Comp shows them at 1.700" installed height at 102 lbs. (I don't ever take a Jegs or Summit listing as gospel for data; I always go back to the mfr data sheets. As an example, Jegs shows the coil bind height as 1.02" so that is different than Comp; I would go with the Comp data sheet number of 1.065".)

So you can put them anywhere in that 1.65-1.7" range. If the 2.2 retainers end up at 1.650" installed spring height with no shims, then you are set. If they end up higher, then you can shim under the springs to get to 1.650", or leave them a bit higher if they're not too much higher.

If a lower installed height results with the 2.2 retainers, then you're gonna have to start looking at coil bind again. Example: 1.630" height - .530" lift = 1.100" and that is only .035" from a coil bind height of 1.065". Not enough...

One other thing you can do to help figure all of this out is to borrow a dial indicator and measure the real valve lift. You're going to lose .005"-.010" of lift from the calculated numbers due to geometry variations at that lift level. So that is going to help coil bind margin. Make sure you measure it on a valve whose lifter is hard and solid when the valve is closed (has a good check valve), not one that is soft (weak, leaky check valve).
 
nm9stheham said:
Yes great idea. What would one do with stock stamped rockers though? Grind down a push rod for exact length for testing? Or use an adjustable p-rod?
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I don't know? Everything I build gets adjustable rockers. Or at least anything built for hi performance use. If stock, I don't worry about it.
 
Just ordered Hughes 1110 springs and I scored 16 nos mopar 2.2 retainers off ebay for 20 bucks shipped. Thanks for the help everyone
 
Is that rust on that other spring in you picture? You can't allow a valve spring to rust. Rust creates stress riser and the spring will break. Always keep them oiled.
 
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