Exhaust manifold broken bolt replacement....... 2012 Dodge Ram

[brino]

I'm over here yapping and brinos out driving around, no leaks no oder. All kidding aside, I hope all went well. Charlie.

Charlie,

Not quite......yet!
Still working on it.

I did not get to spend my whole day on it today with some errands and running to the local tool place for a couple more sets of import 1-2-3 blocks to use while trying to figure out how to bolt this thing down for fly cutting.

I spent some time on the surface plate figuring out support points and mapping the heights.

Pictures coming up.......
Brian

 

[brino]

I finally got the pictures off my cell phone; the USB connection was previously flaky... connected......not connected...connected....not...
I just spent a few minutes fishing pocket lint out of the USB-C prt and now it connects reliably.

I have some great tweezers and dental picks, but do NOT dare use them for this task...... I figure the phone must provide power out this port for USB memory sticks and I do NOT want to cause any issues.... even if they have some fancy resetable fuses.

My previous phone (Samsung Note 3) I could pull off the back with just my finger nails and remove the battery.
My "new" (used) phone is a Samsung Note 10, so I lost that great feature.

Instead I whittle down a wooden tooth pick as the initial size is too thick. I avoid using compressed air for blowing out those ports as I have felt the wind blow-by my fingers while holding the side of the phone while trying it. I figure that's just gonna fill the phone with dust bunnies. This phone is rated IP68 for underwater 1.5 meters for 30 minutes, but obviously those seals can't take much pressure.......

stay tuned.....

 

[Bone Head]

For gaskets these are my go-to guys. I use their MLS gaskets on the Harleys I work on, and following their supplied instructions I have never had a failure. Customer service is good too.
https://www.cometic.com/applications/automotive

 

[brino]

Yesterday I finally got the manifold off:


but was still faced with this, two bolts broken at the head surface:


The bolt to the upper left is rusty and obviously been broken for a while, the one on the bottom right was freshly broken.

I attacked the bottom-right first and got it!
for the top left, I got some photos along the way......first step is to weld on a washer.....


The washer provides two things:
i) a mask so future welds are limited to the window withing the washer ID; I cannot accidentally damage too much of the aluminum head, and
ii) a base for welding on a nut

Note the sharpie marker ring around the washer. I centre the washer on the broken stud, hold it tight and draw around it. That way I can easily tell with the welding helmet on if the washer shifted while I picked up the MIG gun.

then weld on a nut:


give it a turn......................................... and the nut and washer pop right off ...... dang!


okay lets try again...... this time lets try to build up the broken bolt above the surface first.... a little tack:


add the washer and a little more build up:


then add a new nut:


Got it!


to be continued.....


Brian

 

[brino]

Here is the old hardware:


Note that most of the top-left bolt is still in the heat shield. (the original broken bolt)
Middle right is the bolt I managed to break.

Towards the centre are the two broken bolts and the nuts from failed attempts at removal.

To the left of that is the one bolt with the rounded head that I welded a larger nut to as a new head.

Here's the new hardware:


...still more to come.
Brian

 

[brino]

I put the manifold sealing face down on the surface plate:


and see a large gap at the right-most port:


The other port faces were touching the surface plate, but NOT all the way around... there is significant warp!

Using 1-2-3 blocks under the mounting ears, I went looking for a way to hold this for milling while removing the least amount of material.

With a height gauge and dial indicator I mapped the height around each port.
Then moved over to the mill table:



....and started fly cutting the faces:


Yes I only have the manifold supported by the two end flanges....... I likely should put some machinist jacks under there, but I did kept my depth of cut very low......

I will need to take tomorrow off work to finish machining in the morning and get it re-assemble in the afternoon.

Brian

 

[ErichKeane]

Neat! Dorman bolts! So you're planning on doing this job again next year

It looks like you're making good progress. I will say: it doesn't really matter how good a job you do fly cutting those, they just need to be reasonably co-planar. It looks like it is awfully out of wack from years of being heat cycled, so whatever you do will be 'better'. I DO know it is reasonably common to just use a piece of sandpaper and a a benchtop to 'surface' exhausts on older trucks, so I can't imagine the tolerances after a good gasket will be much of a big deal.

 

[Bone Head]

Thanks for taking the time to post your progress; especially taking pictures. Looks like you're going to have a good repair.

 

[deakin]

there are dedicated machines for surfacing manifolds. i have one. that could be done in 10 minutes or less however these days there are not many automotive machine shops around

 

[Charles scozzari]

I put the manifold sealing face down on the surface plate:
View attachment 434679

and see a large gap at the right-most port:
View attachment 434680

The other port faces were touching the surface plate, but NOT all the way around... there is significant warp!

Using 1-2-3 blocks under the mounting ears, I went looking for a way to hold this for milling while removing the least amount of material.

With a height gauge and dial indicator I mapped the height around each port.
Then moved over to the mill table:

View attachment 434677

....and started fly cutting the faces:
View attachment 434678

Yes I only have the manifold supported by the two end flanges....... I likely should put some machinist jacks under there, but I did kept my depth of cut very low......

I will need to take tomorrow off work to finish machining in the morning and get it re-assemble in the afternoon.

Brian

I don't know how you were able to get in there to weld the nuts on but nice work. Glad you were successful. Wow, that manifold bent like a pretzel. A little tricky to jig up for the cut, but I know you'll make it fit right. Thanks for posting.