Hi everyone, i was just gonna put an exaust gasket on my 352 to stop a terrible exhaust leak, but 3 of the bolts broke off in the head, whats my best bet? should i take off the head & while i'm at it, do the valves (engine runs really strong but has either 109k or 209k) & of coarse head gasket to get them out or is there a way i can get them out of there withoght doing head surgery? its the top bolts on cylinders 2, 4, & 6. & i bet if i try the passenger side, they will break off also,
The only way to take the bolts out is to heat the area where the bolts go in the head. Heat the other side before you try to remove the bolts. The ones you have broke will come out after drilling, heating and an easy out. If you can't get to it, it's either pull the head or pull the engine.
^^ what he said. You'll have about as much chance of getting them out successfully with the engine and head still in the car as you would winning the power ball lottery. The only way to do this with any expectation of success is on a bench top.
I've had good luck with sitting a nut over top of the broken bolt, then MIG welding thru the center of the nut to the broken bolt. Kinda like putting a new head on it. The heat from welding helps too.
I have used the "weld a nut on the bolt" meathod COUNTLESS times without even looking towards my drill. Hell, I couldnt even tell you where my easy outs are anymore, havent used them in years.
Hit the nail on the head here, Talked a friend through this the same way on his 352 in a 61' starliner, might take a couple of tries of hot & cold cycle with the mig.
If you can get an angle drill and drill a small hole all the way through them it will make the easyer to heat them red hot. Let them cool and use an easy out. I have also drilled a hole and used a cutting torch. The steel bolt will cut and the cast iron won't. It will only work on the top ones that are not blind.
ok im gonna try the mig welding method & what if i told you that im replacing the driver side fender soon, so taking off the inner fender wont be too much of a problem, that way ill have good access to it and i wont have to take off the head or pull the engine, thanks guys wish me luck, i think ill start on it tomorro after school
Do you have a torch and a good welder? If so get your welder ready (you know if its a mig purge the line) then take your torch and heat up the end of the bolt weld a washer to the bolt then weld a nut to that (if you use a coupling nut it makes it easy ) then let it cool down repeat that proses tell you get it. I keep forgetting to try the wax candle.
haha funny you should mention that, before i tried this, i rant the engine till it was hot and melted tons of candle wax into the holes where the bolts go into
Here are some jigs that I made to drill out broken exhaust bolts. I'm sure they would work for other applications where the bolt is broken flush with the surface. Here's how I use them for broken manifold bolts: 1. Remove exhaust manifold 2. Tap a thread in the manifold hole to match jig thread 3. Re-install manifold 4. Screw jig into threaded hole 5. Drill through broken bolt 6. Repeat process with graduating hole sizes in your jig until most of the seized bolt is removed. 7. Chase the hole with tap. 8. Yo, problem solved <!-- / message --><!-- attachments --> <FIELDSET class=fieldset><LEGEND>Attached Thumbnails</LEGEND> </FIELDSET>
I used an angle drill and an easy-out on my broken exhaust manifold bolts on my 1966 352. Worked like a charm. Then I doubled-up my manifold gaskets, and they have been good for the past fifteen years or so ...
Very common to have the upper exhaust manifold bolts break, as they are on extended ears of the block, and air and moisture attacks both ends of the bolt. I generally heat the ears of the head cherry red before even attempting to remove these. The lower bolts usually will come out with no resistance. I also use the 'welded nut' trick to first try to remove the broken ones, before pulling the head off. ---John
I had a couple exhaust manifold bolts break off in the 352 engine in a F-250 I used to own. I ended up removing the heads so I could do the work on the bench; I was able to drill them out successfully. The big trick is starting the drill dead center on the broken bolt; if there' a stub sticking up above the hole, use a file to flatten it so you can more easily centerpunch it.
so i, took off the fender so i could have easy access that side of the engine, and i tried to weld a nut on over the bolt, but i was working with a mig weldor with gass-less wire & it did dent want to hold & kept breaking off, i diddent try an ark weldor, then i tried an EZ out, i was gonna get the reverse thread ones, but a couple friends at ace told me to use the straight one, after breaking off 2 of those inside the bolt after it sat overnight in penetrating oil and heating it, i could luckily get those out from the top. so then i decided to drill out to the threads, but my, drill bit was to big. so what i decided to do was "make" a stud, ill take like 2" of grade 8 7/16 fine thread and put it through both, the manifold and the head, & put a nut on both sides, i saw this done once, & i'm hoping it works good for me, if not, ill have to tap it out to something bigger
Thats an excellent trick. I would think it would eliminate the hardest part of getting a drill started straight in the center of the broken bolt.
hey guys, what i ended up doing because lack of supplies & tools was i just drilled out the threads compleatly and because all the ones that stripped were ears off the engine, i just put a long bolt through them and put a nut on this side & tightened it like a stud, but for some reason, i cant get the bottom right middle bolt in on the drives side, i spent an hour trying but it wont go in & thread, I'm gonna make the trip to town and get a tap to clean up the threads & get whatever crap out so the bolt can go in, it dosent leak but i bet it will soon if i dont fix that
Bolts that go right through a casting like these heads can be blown out with a fine tip on a torch, done it many times. The cast won't burn with the torch, a tap will clean up the threads and you're laughin'! Works on FE's, 446 IHC's, anything with the hole going right through. A good man with a torch can even get them out of blind holes, but I don't want to try that......And if the threads are damaged, there's always Helicoil.
so like an oxy acetiline torch would work? just dont hold it there too long? & you say not to use a tap?
I`d bet if you removed or at least loosened all the other exh. manifold bolts, and install the stubborn bolt in first, you would be OK. If you look at a FE exhaust manifold, one of the bolts near the middle is a bit smaller from the factory than all the others. That smaller hole positions the manifold more accurately, so if you start that bolt first, providing all the threaded holes in the head are undamaged, the other 7 bolts will go in easily.
ahh, good information Rory, do you by any chance know what size that other bolt is? ill try to google it meanwhile
Actually, all the bolts in the head for the exhaust manifolds are the same size (3/8 NC), it is a single bolt HOLE in the exh. manifold that is a bit smaller than the rest. The tighter tolarance locates the manifold correctly. If you take the manifold off and have a good look, it will be pretty obvious.
ok, i think ill loosen everything to try to get that one in, and i bet ill figure it out, just haven't had time to work on it, hopefully thats to day, thanks guys
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