5.7 Hemi -Tick coming from injector rails?

[Ronsant]

So my 2006 Magnum with 110,000 miles on it has a ticking sound. Having read the “dreaded Hemi Tick” articles and posts, I’m hoping it’s not a disintegrating valvetrain.
I got out the long screwdriver ( aka mechanics stethoscope) and both valve covers are quiet. Same for alternator, pvc valve, and exhaust manifolds.
the “clicking” is most definitely coming from the FI rails. Very audible on the left and right side. Nothing in the intake or water pump.
My question to all the mechanics on the forum is what can be causing a tick loud enough to hear in the cabin relative to the FI rails?

 

[GMBoy]

The evap purge solenoid will make clicking sounds, maybe unplug it and see.

 

[MattPersman]

Hemis are pretty noisy engines in general with the hood open. The injectors can be fairly noisy especially if you are worried about or listening for a tick. Seems to amplify when searching

 

[OVERKILL]

Well, this is a new one! Normally it's the exhaust manifolds. Is this a new development?

 

[hemioiler]

Judging by the year alone, high probability you don't have "lifter tick". That was not really a problem on pre 2009 hemis. Your hemi has dropped valve seat issues when they get too hot. 2009+ is when lifter tick started becoming a real problem.

And yes these hemis are not exactly quiet, even new my truck has been the noisiest engine I've owned especially when cold.

 

[Ronsant]

Thanks for the replies.
I already chanced some broken exhaust manifold bolts.
the noise is very loud with the screwdriver on the rail. Not so much anywhere else.

 

[OVERKILL]

Thanks for the replies.
I already chanced some broken exhaust manifold bolts.
the noise is very loud with the screwdriver on the rail. Not so much anywhere else.

If you can track it down to a particular injector you could unplug it momentarily and see if that has an impact on the noise.

 

[Gasbuggy]

The cam/lifter issues are really MDS engines only.

 

[OVERKILL]

The cam/lifter issues are really MDS engines only.

No, there have been reports of them happening on non-MDS engines (Hellcat) as well, as well as some of the non-MDS 6.4's, but there are so few of them out there that of course the majority that experience the issue are going to have MDS.

 

[Gasbuggy]

No, there have been reports of them happening on non-MDS engines (Hellcat) as well, as well as some of the non-MDS 6.4's, but there are so few of them out there that of course the majority that experience the issue are going to have MDS.

So you agree, it's mostly the mds engines... I guess what I'm thinking of is, he only knows about the ticking from it being such a common issue in the MDS engines. His 06 Hemi, failure rate was low enough it wouldn't become common knowledge.

 

[OVERKILL]

So you agree, it's mostly the mds engines...

You said MDS engines only:

The cam/lifter issues are really MDS engines only.

It also affects non-MDS engines, but since there are VERY few non-MDS engines, the majority that experience it are statistically, going to have MDS.

 

[Gasbuggy]

You said MDS engines only:

It also affects non-MDS engines, but since there are VERY few non-MDS engines, the majority that experience it are statistically, going to have MDS.

I said, "really only". Unless you're on the spectrum, that shouldn't be taken literally.

 

[Gasbuggy]

You said MDS engines only:

It also affects non-MDS engines, but since there are VERY few non-MDS engines, the majority that experience it are statistically, going to have MDS.

"Very Few" uh, they made well into the hundreds of thousands of them from 03 forward without MDS.

Kind of a joke there about taking things literally. I know they all have issues. Just seemed to really be a problem for MDS Hemis. I looked but can't find it. I thought that the camshaft manufacturer changed around the time they went to MDS and that was likely the real issue. "softer" cams.

 

[el Nuke]

The valve train issues you are concerned about are not really a thing for your engine. Those started with the updated version of the Hemi introduced in 2009.

Your issue, if you want to consider it one, is noisy fuel injector(s). It’s not a portent of doom, it’s just a fact of life with a fuel injected engine sometimes.

Listen for it to get worse, and if it does, take steps to mitigate. Until then I wouldn’t stay awake at night worrying about it or anything

 

[zrxkawboy]

The injectors can be fairly noisy especially if you are worried about or listening for a tick. Seems to amplify when searching

I wonder about this, too...if the OP is noticing normal injector operation. You are 100% correct: when searching for a noise, we tend to notice so much more.

 

[OVERKILL]

"Very Few" uh, they made well into the hundreds of thousands of them from 03 forward without MDS.

Yes, very few compared to the number they made WITH MDS, lol. Hence my use of the word "statistically" in the response. Think how many millions of MDS HEMI's were manufactured and out there, then, during the same timeframe, how many were made without MDS? it's very few in comparison.

Kind of a joke there about taking things literally.

Yeah, I suspect some folks with autism on here (of which I'm not one) won't be pleased with that comment, you might want to report it so the mods can delete it.

I know they all have issues. Just seemed to really be a problem for MDS Hemis.

The issue seemed to really come to be around 09+, when they introduced VVT. I suspect this is when they changed lifter suppliers (and camshafts), as before this, with or without MDS, lifter failure didn't seem to be much of "a thing", if at all.

Let's use some made up numbers here to explain why it appears that way. '09+, we are looking at the 6.1, 6.2HC and the 6.4 with a stick, plus however many non-MDS 5.7'S were produced for HD applications before the switch to the MDS 6.4L. Not a huge number. Let's say total production was around 200,000 for the sake of this exercise.

We'll say MDS HEMI's for the same period, which appeared in the Charger, Challenger, 300, Durango, Grand Cherokee, RAM 1500/2500/3500, Aspen and Commander and includes both the 5.7L and 6.4L mill is 8,000,000 (RAM production is ~6 million since 2009).

Let's say the rate of failure is 0.2%, so for every 1,000 sold, 2 of them will have lifter failure.
- For non-MDS engines that means 400
- For MDS engines that means 16,000

So, in the above example, there were 40x as many MDS engines made during that period than non-MDS, so you are of course far more likely to hear of or know of lifter failure with an MDS example than with a non-MDS example even if the rate of failure is identical.

I looked but can't find it. I thought that the camshaft manufacturer changed around the time they went to MDS and that was likely the real issue. "softer" cams.

According to a very informed FCA tech on here, @TeamZero, he has confirmed that it's a materials issue with the lifter roller and/or pin. The defective ones are improperly hardened and so the needles eventually start to wear a groove in the roller or the pin which stops them from rolling around with the roller and once the groove/ditch becomes deep enough, the needles pile-up, which stops the roller from rolling, at which point it wipes out the cam lobe.

There have been MANY revisions of the lifters at this time, supposedly the issue has now been fixed. The newer lifters have larger, fewer needles as one of the changes.

 

[350Rocket]

Yes, very few compared to the number they made WITH MDS, lol. Hence my use of the word "statistically" in the response. Think how many millions of MDS HEMI's were manufactured and out there, then, during the same timeframe, how many were made without MDS? it's very few in comparison.

Yeah, I suspect some folks with autism on here (of which I'm not one) won't be pleased with that comment, you might want to report it so the mods can delete it.

The issue seemed to really come to be around 09+, when they introduced VVT. I suspect this is when they changed lifter suppliers (and camshafts), as before this, with or without MDS, lifter failure didn't seem to be much of "a thing", if at all.

Let's use some made up numbers here to explain why it appears that way. '09+, we are looking at the 6.1, 6.2HC and the 6.4 with a stick, plus however many non-MDS 5.7'S were produced for HD applications before the switch to the MDS 6.4L. Not a huge number. Let's say total production was around 200,000 for the sake of this exercise.

We'll say MDS HEMI's for the same period, which appeared in the Charger, Challenger, 300, Durango, Grand Cherokee, RAM 1500/2500/3500, Aspen and Commander and includes both the 5.7L and 6.4L mill is 8,000,000 (RAM production is ~6 million since 2009).

Let's say the rate of failure is 0.2%, so for every 1,000 sold, 2 of them will have lifter failure.
- For non-MDS engines that means 400
- For MDS engines that means 16,000

So, in the above example, there were 40x as many MDS engines made during that period than non-MDS, so you are of course far more likely to hear of or know of lifter failure with an MDS example than with a non-MDS example even if the rate of failure is identical.

According to a very informed FCA tech on here, @TeamZero, he has confirmed that it's a materials issue with the lifter roller and/or pin. The defective ones are improperly hardened and so the needles eventually start to wear a groove in the roller or the pin which stops them from rolling around with the roller and once the groove/ditch becomes deep enough, the needles pile-up, which stops the roller from rolling, at which point it wipes out the cam lobe.

There have been MANY revisions of the lifters at this time, supposedly the issue has now been fixed. The newer lifters have larger, fewer needles as one of the changes.

Are the 2500 trucks non MDS? My coworkers son owns a 2014 that's been sitting with a bad lifter/cam for a couple years.

 

[350Rocket]

"Very Few" uh, they made well into the hundreds of thousands of them from 03 forward without MDS.

Kind of a joke there about taking things literally. I know they all have issues. Just seemed to really be a problem for MDS Hemis. I looked but can't find it. I thought that the camshaft manufacturer changed around the time they went to MDS and that was likely the real issue. "softer" cams.

It's a common myth that's just because of the MDS. You shouldn't get so upset about being corrected.

 

[D60]

Our '12 has an EM tick but at least in this case it's noticeably different than something like injectors.

For one, it improves with temp (as the EM expands). And it's more like a classic exhaust tick than the quick nail-tapping-a-chalkboard or tap-dancing click of an electrical component engaging.

I isolated the EM tick with rubber fuel hose in my ear, run along the EM/head joint. You'll get a puff puff puff. Very noticeable when you hit it

 

[OVERKILL]

Are the 2500 trucks non MDS? My coworkers son owns a 2014 that's been sitting with a bad lifter/cam for a couple years.

I'm not 100% on the details but if it's a 5.7L, it most likely doesn't have MDS. I believe the HD 6.4L has MDS across the board.