Exhaust Manifolds | Warped

[ffeschjeff]

Just noticed my shield was off passenger manifold, yup 2 broken on that side from what i can see. Drivers side is still see them all in place and shield tight but who knows.
You guys replacing the heat shields also?
My 2016 has 47k miles.

My Driver side shield was tight on all 4 corners until i started to loosen the bolts the front top one was broken and i guess there was enough thread that it held the shield tight while still being broken at the head. just FYI

 

[loopless]

At 108K miles my 2013 5.7 developed the “tick”. It was of course broken exhaust manifold bolts and it was recommended to just get new manifolds rather than trying to resurface the old ones. The shop has seen hidden cracks in old manifolds that come back and bite you. I had one bolt broken off inside the cylinder head. The shop did a very clever thing by welding an extension onto the bolt while it was inside the head and then using that to unscrew the bolt. Thank goodness I did not have to remove the cylinder head.
They gave me the bolt as a souvenir, they had actually welded a nut onto the bolt as well for the removal but that’s missing in this photo.

 

[Hagar1]

Honestly man, i have never seen or heard of a warped exhaust manifold. I have repaired broken manifold bolts a lot of times and never had that issue of warpage. Thats new to me. Usually after removing the manifold and extracting the broken studs, the manifold mounting surfaces gets cleaned and a new gasket with hardware gets installed. Also, a heads up, sometimes the studs will not extract in the vehicle so the head will have to be removed. Then if studs wont come out after trying to extract them in bench, the head will need to be replaced. I have heard from techs at other dealers that they send them to a machine shop to get extracted and repaired. But in the dealers i have worked at, they never recommended doing that. Not sure how well that would work. Hope any of that helps.

Never pulled a head yet for a broken bolt, just weld a nut to the broken bolt and turn it out. No drilling, therefore no risk of destroying a cylinder head.
The MIG welder is your friend.

 

[Jacob Smith]

The cutoff i believe is the 5th gen 18+. I have a 2017 and mine snapped bolts. I replaced with BD Diesel manifolds.

Just picked up a set of these. Not installed yet. Any issues with yours?

 

[PA Ram]

Just picked up a set of these. Not installed yet. Any issues with yours?

No, never any issue with the exception of sealing the ball of the mainifold with the exhaust pipe socket connection. Had leaks on both sides at first. Tried red rtv and still leaked. Finally used some permatex exhaust repair and sealant. Most people have had good luck with the red sealant which is also permatex. Could have been a combination of the sealant and torquing the bolts more evenly. But no leaks after last attempt. The manifold itself never leaked. I honestly can't remember if I used the manifold gaskets it came with or bought my own. I think I may have bought reflex gaskets. One gasket in my set was damaged from shipping and they sent 2 of the same side and they aren't interchangeable. I decided to run mine without heat shields although there is mounting hardware to mount factory shields,but they have their own hardware and aren't using same bolt that holds the manifolds down. My shields were shot and didn't feel like buying a new set. The bolts that held the heat shields on the factory .manifolds are the ones that usually fail. The gaskets do have a deflective shield on the top. I've been running mine like this for 2 years and had zero issues and tow with my truck. The bolts on these manifolds have sleeves in between the head and the manifold which is supposed to allow expansion without snapping bolts like previous manifolds. Manifolds are also beefier so I doubt they'll warp.

 

[Jacob Maguire]

Ordered BD Diesel manifold kit and awaiting arrival. Currently have broken bolts on both driver and passenger sides. Amazed she made it to 199K with OEM hardware in place.

 

[Govtman]

Had my back bolts on passenger side of my '19 classic at about 80K and dealership fixed it, now same tick from both sides till it warms up. So they lasted about 80K each time so far.

 

[Rustypipes12]

Guys if you plan on doing this yourselves and the studs broke off flush it's definitely easier to do the " welded nut trick" to remove them. If not drilling should definitely be done with the block template to help prevent hitting the very close by water jacket!!! .

 

[PA Ram]

Guys if you plan on doing this yourselves and the studs broke off flush it's definitely easier to do the " welded nut trick" to remove them. If not drilling should definitely be done with the block template to help prevent hitting the very close by water jacket!!! .

100% accurate!

 

[Jacob Maguire]

One of the visible broken studded bolts broke off right at the manifold. Should be 'grab-able' once stock manifold is removed from the equation. The others remain a mystery until then... fingers crossed. If needed, definitely welding a nut for removal.

 

[Sherman Bird]

Honestly man, i have never seen or heard of a warped exhaust manifold. I have repaired broken manifold bolts a lot of times and never had that issue of warpage. Thats new to me. Usually after removing the manifold and extracting the broken studs, the manifold mounting surfaces gets cleaned and a new gasket with hardware gets installed. Also, a heads up, sometimes the studs will not extract in the vehicle so the head will have to be removed. Then if studs wont come out after trying to extract them in bench, the head will need to be replaced. I have heard from techs at other dealers that they send them to a machine shop to get extracted and repaired. But in the dealers i have worked at, they never recommended doing that. Not sure how well that would work. Hope any of that helps.

I do not know your years in the field, nor do I know the breadth of your experiences.
Cast iron manifolds WARP. That's just physics. By how much can generally only be determined by a machine shop surface grinding the manifolds, and, as per my own experiences with Chrysler 383/440 engines and GM's HT4100 engines back "when".

Many was the time I'd replace the broken bolts and the subsequently leaky gaskets, only to see repeat failures.
Then, on a 7 ton motor home with a 440 Chrysler engine, I got tired of repeating the repairs to the exhaust. (This was way back at about year 9 of my career).

An older seasoned mechanic instructed me to have the manifolds surface ground, and to be honest, the machine shop said the warpage was only in the .003-4 range, but he surfaced them anyway, per the older seasoned mechanic.

Then as instructed by afore mentioned seasoned mechanic, the cylinder heads were meticulously cleaned off.
Thence, the manifold to cylinder head gaskets were shelved (omitted), and a can of high temp engine enamel was sprayed onto the freshly ground surface of the manifolds and, while tacky, they were installed using HIGH TENSILE strength bolts/ studs. Then, the engine was fired up and allowed to idle for about 1-2 minutes, and shut off, to allow heat to accelerate curing. Left for about 3-4 hours.

It sounded counter intuitive, but I was frustrated and willing to try it. It not only worked then (more than 40 years ago), it continues to work even now.

I've cured many engines of the problem by doing this. The problem today, is finding a machine shop willing to grind the manifolds. I recently installed new Dorman manifolds on a 2002 4.7L engine during engine replacement, emphasizing that I DID go purchase very high tensile strength bolts at my neighborhood fastener shop. They were NOT cheap, either. For all the bolts and special hardened washers, I spent north of 30 dollars.

 

[EdGs]

The problem today, is finding a machine shop willing to grind the manifolds. I recently installed new Dorman manifolds on a 2002 4.7L engine during engine replacement, emphasizing that I DID go purchase very high tensile strength bolts at my neighborhood fastener shop. They were NOT cheap, either. For all the bolts and special hardened washer, I spent north of 30 dollars.

Good ole belt sander does wonders getting them flat. Takes a little time, but very effective.

Once they've been heat-stressed, warped, and then sanded or ground flat, usually they are good-to-go.

The newer Ram manifolds have bars installed on them, and it seems those manifolds like to crack.

 

[Sherman Bird]

Good ole belt sander does wonders getting them flat. Takes a little time, but very effective.

Once they've been heat-stressed, warped, and then sanded or ground flat, usually they are good-to-go.

The newer Ram manifolds have bars installed on them, amd it seems those manifolds like to crack.

Older SB Chevy's did too. The trick was/is to hacksaw through the bars at the center between ports. This stress relieves said iron, and doesn't attempt to outrun physics!

 

[EdGs]

Older SB Chevy's did too. The trick was/is to hacksaw through the bars at the center between ports. This stress relieves said iron, and doesn't attempt to outrun physics!

I've always wondered if they weren't stress relieved after casting.

Like, after heat-treating some steel. It gets treated a 1725° for X time, then after it cools, it gets brought back up to 500° to normalize it.

Don't know much about how cast iron gets treated, though. Our exhaust manifolds like to warp like a banana....

On mine, they warped at least .060, and twisted a bit, too.

 

[Sherman Bird]

I've always wondered if they weren't stress relieved after casting.

Like, after heat-treating some steel. It gets treated a 1725° for X time, then after it cools, it gets brought back up to 500° to normalize it.

Dob't know much about how cast iron gets treated, though. Our exhaust manifolds like to warp like a banana....

On mine, they warped at least .060, and twisted a bit, too.

The lowered carbon (graphite) in cast iron these days is a problem. This is why I throw the budget away on brake rotors and spend the bigger bucks on high carbon rotors (graphite). (G3000 min. specs)

 

[Hagar1]

I've always wondered if they weren't stress relieved after casting.

Like, after heat-treating some steel. It gets treated a 1725° for X time, then after it cools, it gets brought back up to 500° to normalize it.

Dob't know much about how cast iron gets treated, though. Our exhaust manifolds like to warp like a banana....

On mine, they warped at least .060, and twisted a bit, too.

Nothing is stress relieved now a days. I betting that the manifolds are barely cool before the hit the machine shop.
In the manufacturing arena, the freshly cast component is referred to as being "green" cast. Manufacturers look at the cost of replacing some versus the cost of putting them through a thermal cycle to stress relieve. Guess which process won?
Remember the "old days" of building a high output engine? Always started with a high miler. Look at the old "Direct Connection" catalogue. The offered "stress relieved" engine blocks.

 

[Jacob Maguire]

Just followed up with BD Diesel as nothing but an order confirmation has been received since order placed 2 days back. Apparently, to their surprise, they've located the parts in a PA warehouse. Hopeful they will arrive by this weekend. Fingers crossed...

 

[Nick@GotExhaust]

For anyone looking for BD Diesel manifolds we have plenty of them in stock. Message me for a quote.

 

[Sherman Bird]

Nothing is stress relieved now a days. I betting that the manifolds are barely cool before the hit the machine shop.
In the manufacturing arena, the freshly cast component is referred to as being "green" cast. Manufacturers look at the cost of replacing some versus the cost of putting them through a thermal cycle to stress relieve. Guess which process won?
Remember the "old days" of building a high output engine? Always started with a high miler. Look at the old "Direct Connection" catalogue. The offered "stress relieved" engine blocks.

And all this time, I thought stress relief was in the form of an adult beverage and a couple of pills!

 

[TomT]

And all this time, I thought stress relief was in the form of an adult beverage and a couple of pills!

That’s just what the guys on the assembly line have for lunch.