chrisjpr
Owosso
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My Tioga Ford / 460 class C needs the drivers side exhaust manifold gasket replaced. After examining the manifold and all the bolts I have come to the conclusion that I am not about to attempt this repair. I called my highly reputable local Ford garage and spoke with the mechanic. He has been there for almost 30 years and has litterally replaced hundreds of these manifold gaskets. He explained that he will have the manifold belt sanded for trueness. Then he said they will "oval" out the bolt holes to allow expansion and contraction. Lastly he will reinstall the manifold with a new gasket and new bolts. He wouldn't quote the job over the phone though. He didn't seem concerned about bolts breaking off in the head and having to remove the head either. Any idea or input on what this should cost? My local "jo blow" muffler shop wanted $500.00 per side and was convinced that he would have to pull the head. I'd rather have someone who has experience with this particular issue that seems to be so common. Any input would be appreciated.
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omatty
nashville, tn
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Joined: 04/04/2012
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seems to me hes taking your money by belt sanding and drilling the bolt holes. If expansion and contraction wasn't an issue before it wouldn't be just from replacing the gasket. I've changed MANY manifolds and have NEVER had an issue with either one of those things.
The only reason that i know of to remove the head would be if clearance was an issue.
just my 2 cents
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hilldude
Red house WV
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I replaced the exaust manifold bolts on a 460.Did it myself, took it two local garages would not quote a price. Had to remove heads and take to machine shop to get bolts out.installed hedman headers from summit racing.I think it was 87 E350,some bolts were broken and some broke getting them out.The motor home had 75,000mi and no wear on cylinders.
* This post was
edited 04/23/12 09:14am by hilldude *
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Normk
Canada's Wet Coast
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Your Ford mechanic gave good advise.
A leaking manifold gasket is the result of either poor manifold to cylinder head fit or aging of the gasket. Unless the surfaces are in very good condition, the time required to remove the manifold and resurface (which is what he will mean by "sanding") is a good investment. He will not want to simply move the manifold out enough to slip in a new gasket as this is likely to come back on him later if the gasket fails.
Manifolds often warp due to the extreme heat and so increasing the size of the holes is a common practice in order to save time in reinstalling. The time required to run a drill through the holes is not going to add significantly to your bill and avoids fighting with fitting.
A dealership will almost certainly replace the bolts which is good practice also, given that they will be heat damaged. He will almost certainly use an anti-seize compound on the new bolts which will save grief later. I like to replace the bolts every year or two (depends on how hard you work the engine. They are easy enough to replace, one at a time with manifold in place and this can save a broken one later. Use anti-seize!
Shops should warn you regarding the possibility of a badly seized bolt/or broken bolt which cannot be accessed for drilling with manifold in place. This will require more labor and so cost more, not rocket science and the mechanic didn't make the rig, doesn't own it, and doesn't drive it so the owner owes the bill.
In some locations (passenger side is my favorite) it is simpler and less costly to remove the cylinder head in order to extract a bad one. Although this seems excessive, the broken section needs be drilled out with almost perfect alignment and this can be nearly impossible in place. Drilling off center or out the side of the broken section into the head locks it into place and really raises the difficult level.
Good luck with it, put the job into the hands of someone experienced and competent, then trust that they have done the best thing.
This is not the ideal first project for removing a broken fastener.
HIH
Norm
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chrisjpr
Owosso
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Normk wrote:Your Ford mechanic gave good advise.
A leaking manifold gasket is the result of either poor manifold to cylinder head fit or aging of the gasket. Unless the surfaces are in very good condition, the time required to remove the manifold and resurface (which is what he will mean by "sanding") is a good investment. He will not want to simply move the manifold out enough to slip in a new gasket as this is likely to come back on him later if the gasket fails.
Manifolds often warp due to the extreme heat and so increasing the size of the holes is a common practice in order to save time in reinstalling. The time required to run a drill through the holes is not going to add significantly to your bill and avoids fighting with fitting.
A dealership will almost certainly replace the bolts which is good practice also, given that they will be heat damaged. He will almost certainly use an anti-seize compound on the new bolts which will save grief later. I like to replace the bolts every year or two (depends on how hard you work the engine. They are easy enough to replace, one at a time with manifold in place and this can save a broken one later. Use anti-seize!
Shops should warn you regarding the possibility of a badly seized bolt/or broken bolt which cannot be accessed for drilling with manifold in place. This will require more labor and so cost more, not rocket science and the mechanic didn't make the rig, doesn't own it, and doesn't drive it so the owner owes the bill.
In some locations (passenger side is my favorite) it is simpler and less costly to remove the cylinder head in order to extract a bad one. Although this seems excessive, the broken section needs be drilled out with almost perfect alignment and this can be nearly impossible in place. Drilling off center or out the side of the broken section into the head locks it into place and really raises the difficult level.
Good luck with it, put the job into the hands of someone experienced and competent, then trust that they have done the best thing.
This is not the ideal first project for removing a broken fastener.
HIH
Norm
Thanks Norm!! I was wondering though, why couldn't the mechanic remove the inner and outer fender to access the broken bolt? It would seem that this would be much easier than pulling the intake and head. The driver's side is the side that needs servicing on my unit.
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Normk
Canada's Wet Coast
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The driver's side is the "easy" one. Drilling the broken bolt segments is a really interesting excercise requiring that one can locate and control the drill quite accurately. One may not be able to see the area well enough to control the drill, may not be able to fit the drill into the area, etc.
Right angle drills are a great advantage but cannot solve all problems. I wonder about the use of a USB inspection camera as mine would seem to lend itself well to some locations however these are newer to the field than my contact.
In some cases the 460 breaks out around the boss of one exhaust bolt hole which requires either replacment of the cylinder head or welding repair of the area. If memory is correct, this usually affects an end hole.
Despite that some customers may asert that some mechanics may seek to break bolts in order to increase the labor time, my 50+ years of experience with the trade makes me discount this. Drilling broken bolts is less than fun and if something goes wrong such as one inadvertently drilling out of line, it would be difficult to make a case to excuse the error.
You seem to be handy mechanically as you comment indicated that you considered undertaking the work. If one is gray haired and not pennyless, having it done is seldom the worst decision, IMO. I do recommend that you consider buying a new set of bolts and a can of anti-seize. You can exchange the bolts one-by-one at convenience and avoid the problem in future.
I prefer black finish bolts rather than plated for this application as they seem to endure longer. I could not prove this. The consensus amoung the top mechanics/technicians I knew in the course of my tool business were agreed that one should use Grade 5 rather than lower or higher grades. Grade 2 or 3 are of weak material while Grade 8 achieves its higher strength by heat treatment which is normalized by exhaust heat.
Avoid stainless fasteners/bolts for exhaust applications!!!
One can support this assertion in two ways:
1) Heat stainless steel and see how hard and brittle it becomes. Now consider drilling that material!
2) Ask any heavy truck engine mechanic about drilling out stainless exhaust bolts & studs.
Good luck with the repair!
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Dakzuki
Carnation, Wa, USA
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Manifold bolts breaking and the resulting leak is a chronic issue with the 460. Ford has known about it for years and have been unable or unwilling to do anything about it. I have a broken one on mine. Let go 6 months after I bought it with about 45k on the engine. My leak seals itself as soon at the parts get warm.
2011 Itasca Navion 24J
95 Chinook Premier
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crasster
Dallas
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Just letting you know, they sell VERY long drill bits at harbor freight tools. Some are are 3 ft long.
4 whopping cylinders on Toyota RV's. Talk about great getting good MPG. Also I have a very light foot on the pedal. I followed some MPG advice on Livingpress.com and I now get 22 MPG! Not bad for a home on wheels.
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F1bNorm
Gardena, CA
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Joined: 11/10/2004
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Dakzuki wrote:Manifold bolts breaking and the resulting leak is a chronic issue with the 460. Ford has known about it for years and have been unable or unwilling to do anything about it. I have a broken one on mine. Let go 6 months after I bought it with about 45k on the engine. My leak seals itself as soon at the parts get warm.
Same here. Had a '77, '86, and a '96. All leaked and then stopped after they warmed up (at least I couldn't hear it). Did check on a fix and was referred to the local EDM shop. Can't remember the quote, but it was high enough for me to tell them I'd be back if it got worse.
- Norm
F1BNorm
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j-d
Sunny Florida USA
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I did this project on a 460 in our 83 E350. The ends of the manifolds were warped. I was fortunate to be able to remove all the bolts without breakage. I learned from hammering an undersize socket onto a wasted bolt (sorry Norm, capscrew...) on the passenger side head that beating on the heads loosened them more than the sprays I'd tried on the driver side. Then resurfaced by machine shop with "belt sander" which is actually a precision machine, nothing like a woodworker's sander.
Reinstalled with new capscrews and new "heat shield" gaskets. These are stamped steel, not the waffle stuff. Waffle won't hold up. NeverSeez on all surfaces as well as the capscrews. Torqued only till the gaskets crushed.
I believe two things I then did kept the problem from coming back. First, I upgraded the exhaust to 3" mandrel-bent with big block muffler from Flowmaster. Second, I stopped abusing the manifolds. Instead of a quick exit from the interstate, fast move into the fuel stop and immediate shutdown, I began to slow down early and let the engine idle a few minutes before shutdown. I believe that helps everything cool gradually and simultaneously.
God Bless, jd
2003 Jayco Escapade 31A on 2002 Ford E450 V10 4R100
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