Engine noise and broken exhaust bolt (updated with pics)

[super_camper]

My Jayco class c is on a 2006 E450 with 60,000 miles. On the last two trips I noticed a new noise. It's really just louder engine noise and is linked with the engine RPM. Funny thing is it only occurs under load and only for the first few times a load is added after starting. After this time it's gone until the next start.

I pulled the doghouse to look at the exhaust and found that one bolt on the passengers side (2nd from the back) is missing, seems to have broken off. I've read about this problem with older Fords but not such much with the 2006 or later.

Now for my questions:
Would one missing bolt cause this type of noise?
Whats involved with repairing this? (It will go to a garage for the repair)

[dawsty]

Give it a shot of "liquid wrench" and let it soak in for several hours.

eric1514 wrote:
If the bolt is broken off evenly with the outer edge of the manifold, you may not have to remove the manifold. Very careful drilling and an EZ-Out should remove the remaining portion of the bolt. The bolt is under no stress right now and should spin easily.

Experience doing this is helpful, but if what you describe is true, it's not a tough job.

Many Good Lucks,
Eric

[super_camper]

My neighbor came over and took at look, he is a retired mechanic. In addition to the broken stud the rear stud is cracked. He has every tool they make and tried to see if the studs would move but no way, so its going into the shop today.

The shop runs two shifts and the light trucks are serviced in the late shift, the machinist is also not available on Mondays so I should know what's involved to get this fixed by tomorrow.

[tboss]

remove the carpet around the doghouse on that side ,,cut out a portion of the floor big enought to give you access to the stud ,,after the stud is removed have the floor welded back in place and a little bondo and paint will fix he rite up..or pay some one a 1000 bucks to remove the head to repair it

[Harvard]

j-d wrote:
....
This is to get the manifold out of the way without breaking any more of he studs. Then work carefully toward removal without the manifold in the way.
...

In my experience with the studs that did break in the removal process, it was like all I had to do was breath on them and they broke. In other words, about the ones that broke, they were just held in place with a surface "rust bond".

[j-d]

I'm trying to think of a way to get the rest of the nuts off in the event the manifold has to be removed. Heat each nut with oxy-acetelyne torch? Split each nut? If so, Dremel Tool? Torch? Plasma Cutter? Mechanical Nut Splitter?
This is to get the manifold out of the way without breaking any more of he studs. Then work carefully toward removal without the manifold in the way.
By the way, I beliece it's possible to "abuse" our exhaust manifolds. Run down the interstate at full cruise speed, duck into a rest area, nose into a slot, turn the key off and run inside. All that metal has to transition from Hot as they Get to Sudden Cool Down. Can't be good. If it's a quick stop, leave somebody aboard and let it idle. For a long stop, let it idle into a cooldown then shut it off.

[ron_dittmer]

Adding: In the picture, it looks as though you might be able to use a very fine needle-nose pliers to get it out. I mean "Very-Fine" needle nose pliers. If you can't find one, sacrifce a standard one by grinding it to a fine point.

[bsinmich]

When I had a broken stud in my '89 E450 my mechanic called in a portable EDM guy and actually got the bolt out that way. That was a long time ago but I think the added cost was around $60. at that time.

[ron_dittmer]

Odds are that stud is in there loose. Try a very short pencil with an eraser. Push the eraser against it hard and unscrew it. It might come out.

If not, "lightly" tap on the stud with a punch & hammer and then retry.

If no luck, try a good adhesive like JB Weld. Glue an allen wrench on it. After the glue has cured well, spray some PB Blaster (a penetrating oil) then carefully unscrew it. Any movement is good. Just work it left/right/left/right.

If all is hopeless, find someone skilled in detailed welding. He/she might be able to tack weld a bolt to that left-over piece. Then you have something to put a wrench on.

[ol__yeller]

Sorry double post.

[ol__yeller]

The problem is that the gasket is now compromised and the manifold is also probably warped. To do this job right, the manifold has to be removed and then resurfaced and new gaskets installed. In that process several more studs will likely break. The problem is that the cast iron manifold is so long that it moves quite a lot during heat cycles (expand and contract) and the cheap studs Ford installed can't take the movement so they break. That is also why many go to headers instead if the cast iron manifolds. You can achieve some measure of longevity to your repair job by installing stainless steel studs and nuts and using a good antisieze compound. It is not a quick job and it can get expensive to have a mechanic (or machinist) do the work.

Sorry for the bad news from someone who has been there.

[rode2nowhere]

the f150 I had was like that, I traded it off but ford make replacement studs made of stainless.

[GrumpyandGrandm]

A friend repaired his in a class "A" while camping at Disney World. Used the procedure similar to what eric1514 described. He actually drilled them out and re-tapped the head then used new (larger) bolts.

[rode2nowhere]

can you get better access underneath ?? And maybe pull the tire off??

[eric1514]

Take it to a machine shop, not a mechanic.

Eric