360 Magnum valve train noise

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Abodysrule

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My 360 magnum is awesome. It made 375 hp/425 lb-ft of torque on the dyno. It has excellent oil pressure and runs smooth as a watch. No oil leaks, runs cool. I'm running FiTech TBI four barrel, it starts instantly, good response and runs great. I absolutely LOVE driving my A-body. My '67 dart has never had a better powerplant.

But, it has valve train/lifter chatter at idle. It doesn't when I accelerate, only at idle. I've read a ton of forum posts on this, apparently the 360 magnum is known to have this issue. One post said "just run 20W-50 and it'll quiet down...". I'm curious why this issue even exists. Anyone else have this issue? I'm not worried so much as annoyed. I've had Ford, Chevy and even other Chrysler small blocks with hydraulic lifters, never had this issue.

What gives?

Brian
 
the inherent design of the lifter causes this to some degree.

but, it may be something else entirely. you didn't give us any other specs, so i'll paint with a broad brush:

wrong oil viscosity. worn lifters-- mileage/age, push rods too short for cam, thick head gaskets, detonation, valves sunk into heads... or, an exhaust leak.
 
OK, maybe I'll try that on the next oil change, thank you.

The engine is a new build, so shouldn't be any of the things you outlined. Not an exhaust leak, but sounds similar.
 
I've had one magnum that randomly got lifter noise it idle while hot. Did an oil change and it went away and never came back. 50k miles later I've Never figured out why
 
Abodysrule said:
My 360 magnum is awesome. It made 375 hp/425 lb-ft of torque on the dyno. It has excellent oil pressure and runs smooth as a watch. No oil leaks, runs cool. I'm running FiTech TBI four barrel, it starts instantly, good response and runs great. I absolutely LOVE driving my A-body. My '67 dart has never had a better powerplant.

But, it has valve train/lifter chatter at idle. It doesn't when I accelerate, only at idle. I've read a ton of forum posts on this, apparently the 360 magnum is known to have this issue. One post said "just run 20W-50 and it'll quiet down...". I'm curious why this issue even exists. Anyone else have this issue? I'm not worried so much as annoyed. I've had Ford, Chevy and even other Chrysler small blocks with hydraulic lifters, never had this issue.

What gives?

Brian
Click to expand...
I run a Magnum based motor with aftermarket adjustable rockers. It's not noisy. Does the motor you have also have adjustable rockers in it? I forget if the stock lifters are adjustable or not.

Either way, are you able to determine how much your lifter's plungers are preloaded or how far down it's compressed from full extension?

I've used a wire gauge to measure my hydraulic lifter plunger's depth from the retaining clip before, but the intake had to be removed for that.
 
This is just a thought. Running headers ? Sometimes you will hear at idle what sounds like a faint lifter tick.
I have found this on budget headers such as Jegs or Summit that are made from thinner gauge steel.
Again just thinking out loud.
 
jbc426 said:
I run a Magnum based motor with aftermarket adjustable rockers. It's not noisy. Does the motor you have also have adjustable rockers in it? I forget if the stock lifters are adjustable or not.
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stockers are stamped steel and non-adjustable.

i'm *guessing* that if a different weight oil, or an oil change has been tried, then it's some type of preload issue. which could be *gestures broadly* any of these [choose your own adventure].
 
You've left out so much info that it's virtually impossible to pinpoint. It's GREAT that you have FI Tech though...... Anyway, cam specs, lifters used(new or used), pushrod spec, and rockers used is a great place to start. Otherwise it could just be a frickin muffler bearing.
I'm going out on a limb and guess whoever put it together either didn't get correct pushrod measurements, or, the lifters are dirty. As in, internally dirty. Either didn't get the used ones clean enough or didn't bother to open up the new ones to check for debris.
 
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Running 20w50 would make it tick louder, thinner oil will lube up the top end faster.

I would run 5w30 Conventional.

One thing you have to remember stock magnums had a **** load of preload Hughes recommends .090/.120 preload.
 
Abodysrule said:
OK, maybe I'll try that on the next oil change, thank you.

The engine is a new build, so shouldn't be any of the things you outlined. Not an exhaust leak, but sounds similar.
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If this doesn't work, you can always grab a set of adjustable pushrods. Manton or Smith Bros will ship you a length testing pushrod. It's a pretty straight forward process to put it in, set the length that gives you the correct lifter preload, verify that this length is different than what you have, and send it in for a new set of the correct length ones.
 
If the 'ticking' is from lifters bleeding down, thinner oil will make the noise worse, not better [ post #10 ]. You hear the noise at idle because there is more time for the lifters to bleed down, whatever the cause of the internal leakage is [ wear, dirt, low oil pressure ].
 
junkyardhero said:
the inherent design of the lifter causes this to some degree.

but, it may be something else entirely. you didn't give us any other specs, so i'll paint with a broad brush:

wrong oil viscosity. worn lifters-- mileage/age, push rods too short for cam, thick head gaskets, detonation, valves sunk into heads... or, an exhaust leak.
Click to expand...
Also add **** in the check valves of the lifters to your list. 95% of the time when a hydraulic makes noise AND is adjusted correctly (proper preload) the check valve has trash in it. Steve Brule told me once “hydraulic lifters are like tiny little oil filters, they catch everything “.
 
Since it does this when running, this is probably not it, but there is a right and wrong way to install Magnum lifters.
 
TT5.9mag said:
Which is? :poke:
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The oil supply hole in the side should face the center of the engine. If installed facing the outside, they can drain oil out of the lifters when the engine sits and get ticking on startup. But since his is doing this while running, I'm sure that's not the case.

To the OP: Brian, when this was built, was proper pushrod length checked for? Nearly all aftermarket rollers are ground on a reduced base circle, so longer pushrods may have been needed. Just a thought.
 
RustyRatRod said:
The oil supply hole in the side should face the center of the engine. If installed facing the outside, they can drain oil out of the lifters when the engine sits and get ticking on startup. But since his is doing this while running, I'm sure that's not the case.

To the OP: Brian, when this was built, was proper pushrod length checked for? Nearly all aftermarket rollers are ground on a reduced base circle, so longer pushrods may have been needed. Just a thought.
Click to expand...
Yup. Post 12
 
RustyRatRod said:
The oil supply hole in the side should face the center of the engine. If installed facing the outside, they can drain oil out of the lifters when the engine sits and get ticking on startup. But since his is doing this while running, I'm sure that's not the case.

To the OP: Brian, when this was built, was proper pushrod length checked for? Nearly all aftermarket rollers are ground on a reduced base circle, so longer pushrods may have been needed. Just a thought.
Click to expand...
I knew you knew.
 
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