460 Ford cylinder head -exh bolts broke off part of flanges

Date 03-13-2007 19:46

can anyone suggest a fix for a problem I just discovered. I bought a dynamite F-350 4x4 chassis cab with a 460 engine & known exhaust leak. I thought it was manifold gaskets...but being it was a snowstorm in january when I bought it...I missed the true issue causing the exhaust leak. The previous owner apparently wasnt much of a mechanic and instead of using some heat to help take exhaust manifold bolts out....he must have used a big breaker bar...because he broke pieces of the cylinder head bolt boss/exhaust flange off and THATS why it really trumpets the exhaust leak.

My Question: what would be the BEST method to restore the "meat" on the flange to provide a sealing surface for the gasket? I have been told that nirod will make the cast iron very hard and brittle and is the worst thing I could do...not having a furnace to preheat the whole heads....Im told to around 1100 degrees.

I have had success in the past bronze brazing broken cast iron brake calipers and the like....but their section width/mass doesnt compare to a cylinder head...that might be like a heat sink. I wonder if I could get enough heat on the remaining flange to build up with braze or possibly braze a pc of steel on it and grind/file to provide a gasket surface....the flange IS a protrusion from the head & not the head proper

other than minor pcs like the brake caliper...Im not experienced with cast iron....any help appreciated.
I thought about rebuilt cylinder heads & just replacing...but local shops are talkng $750 each & the internet prices appear about half that with shipping over $125......not a option for a plow truck that runs great...but is louder than heck in the cab (and melts plug wires for breakfast)

any experiences/suggestions appreciated

By Molten Metal (**)

Date 03-14-2007 00:26

I have had pretty good luck just pre-heating cast iron and Mig welding it with 75%25%,and some er70s-6 electrode.Then try to have it cool really slow.You can use a propane torch for the cool-down.Just clean/grind it as best you can first ofcourse.

By billvanderhoof (****)

Date 03-14-2007 03:27

If you build up the flanges you should at least check with a straightedge for possible warping. A junkyard head is a possibility combining the parts it comes with and the parts in your head possibly with a trip to your friendly local machine shop for a valve grind should result in a pretty fresh head.
Bill

By welder5354 (**)

Date 03-14-2007 04:03

Hi There; I've had good success with welding cast iron using Everdure 254 rod.
It is a soft bronze rod and used with the tig process. Apply most of the heat to the rod and not the base metal.
Try it on a piece of scrap metal to make sure it is what u need.
This rod is also excellent for welding galvinized sheet metal (no fumes and very fast).

By 2003440 (**)

Date 03-14-2007 04:36 Edited 03-14-2007 14:08

Hello just to drop in on the subject i went through the whole spill on exh leaks on my 1995 f450 460 i replace the r/h head due to the rear bolt broken in the head i was able to remove it but the lack of meat on the corner when i torq the manifold bolts it cracked on the corner so i replace the head and the ypipe assy to the manifolds because they collapse and ford has made them with a piece that goes in the manifold so they dont collapse i would not waste time just do it right you will be happy in the long run.

By chapman14219 (*)

Date 03-14-2007 06:39

thank you fellas....the last response sounds like something that my dear old dad would say...without a doubt Id be happiest replacing them...but then again....I guess Im (cheap) adventurous...Im gonna probably try fixin....take it as a challenge.....not gonna waste too much time though...the first flange will be make or break...I cant ruin it any more than it is...Its really a shame because the engine runs very well...I dont like the exhaust noise but...for the kind of money at stake... if it wasnt burning up plug wires...I might not be so inclined to fix it

Could that everdure 254 be used with a oxy/acetylene brazing torch?...and how is the everdure different from the common brazing rod I have????...what kind of flux is used?

anybody ever use cast iron rod with a brazing torch???

its gonna be a bit before I do this ....its a plow truck and the snow is almost all melted here now....but its gonna get cold at the end of the week...so why freeze trying to do this now?...Ill wait till it gets a bit warmer for good.....feel free to jump in with any more thoughts & Ill keep looking for replacement heads that are more affordable

By Bill M

Date 03-14-2007 18:25

I have used a product - SIFBronze mfg. cast iron filler rod / flux combination. We got it from a company in England. It was intended as an oxyfuel weld filler material used with a powder flux. The filler rod was a casting. To make the stick, it actually looked like they poured the molton iron metal into the vee of a flat piece of angle iron and let it freeze. The process worked pretty good, but the high preheat and req. post heat caused enough thermal distortion to require machining afterwards. (I don't work there anymore...or I'd send you a stick to try).

This "seasoned" welder in our shop told me that when he was a kid they used to weld cast iron together using a torch and some old cast iron piston rings as filler.