Removing exhaust manifold bolts?

Dave,
If the socket head hex's are accessible from the top and not blind (a section of the casting close to the top of the bolt) then you may want to try one of these:


.hex socket head extractors - bottom of page 2814

If not then you may be able to get a vise grip on it. If that doesn't work then a Dremel tool with a cut-off blade to cut the heads off is another option.

Do use some penetrating oil like Kroil or PB Blaster (not WD40 - worthless s***) and some heat.

BTW, on tough to break loose socket heads, never use a worn allen wrench or one of the "ball-point" hex keys.

Another idea might be to put new hex bolts back in the places where the others came out. Snug 'em up and that will take pressure off of the others.

And maybe use a cold punch smaller than the hex head and a sharp blow for an attitude adjustment. I haven't seen what Pete posted until now, but I'd use that or an easy out after the 'adjustment'.

86BFN wrote: You could also drill the head off. once you remove the manifold it will be easer to get the rest of the bolt out. PB blaster works great!

Steve,
A socket head cap screw has a higher tensile strength than a grade 8 bolt consequently they aren't the easiest to drill even with a carbide bit. They are hard - min. Rockwell C39!!! Have you even tried drilling one?

They do make stainless ones and with some anti seeze you'll never have any trouble again

I tried drilling the heads off and Pete is right...it's nearly impossible even with a carbide bit. I am going to try using my Dremmel to cut them off but was wondering which particular Dremmel wheel I should use. I also plan to heat the them with a torch and wack them with a punch to set up vibration so I can get the penetrating oil to suck down into the threads as it cools. I like the idea of putting the new bolts in and tightening them to help relieve the stuck bolts.

I have never had such a hard time removing the manifolds on other(hot rod)projects. Maybe it's just a Ford thing, lol!!
Thanks for all the great imput!

Dave,

I just removed my manifolds. I broke off one of my bolt heads. Luckly it was just the head and there was enough of the bolt sticking out that i could get a pair of vice grips on it. I was told to take something like an ice pick or finer and pick around where the bolt goes into the engine. I was able to get some of the rust out of the threads. I also used the PB blaster. I kept working it for about 4 days and when i tried the vice grips it came right out. good luck

Definately taking my time...I have been trying to drill the heads off without much progress. It's time to try some new tricks. I have a torch, chisels, dremmel, cold case of beer, etc to spend the weekend on this project. I have been very cautious not to screw up the manifold flanges.

With enough work and patience, I WILL get them off. I have all new bolts and bunch of other new goodies coming from Skidim...and spring is on it's way! I can't wait to get back out on the water for some fun in the sun. Now, if we could just get out of this severe Texas drought we are in to fill up the lake...

use this if you are using your dremel tool

cut an x in the head and then use your cold chisel to pop them off the rest of the way if you cannot get to it to cut it off perpendicular to the thread body.

79,
I forgot the X-cut trick. Removed a lot of chassis rivets like that. Cut a X then use a rivet gun with a chisel. Oh wear ear plugs!

Dave, I use High temp disk brake caliper paint on my manifolds. It will still burn off down low by the exhaust ports but otherwise it holds up very well and has a nice gloss to it.

I agree. I plan to dip these parts and will inspect for any damage. This boat has spent it's life running two lakes in our area that are full of hard calcium water so I do see a lot of white build up on the inside of the risers. I might try soaking them in CLR before dipping them just to see how much of the hard deposits I can remove.

I had one of the stock manifold drain plugs that was stuck like chuck so I drilled it out. I found some nice brass 3/4" plugs with outer square bolt heads at Lowes to replace the stock recessed type of plug. This will make removal of these things MUCH easier. I can't wait to get these things restored and back on the boat.

Next up, I plan to pull the prop and get it to the Nettle's Prop Shop for a re-do. While I have it off, I want to replace the strut bearing and check my alignment. After that, I should be good to go for the summer.

Dave D. wrote: I found some nice brass 3/4" plugs with outer square bolt heads at Lowes to replace the stock recessed type of plug. This will make removal of these things MUCH easier.

You're saying you replaced the square socket plug


with a square head plug?


I like the top one better. The bottom variety seems much easier to strip. Don't overtighten and you won't have any problems with either.

What kind of tool(s) were you using? All you need is a 1/2" drive socket wrench. I do agree that you will have an easier time removing a stripped square head over a square socket plug.

You were not able to get a 1/2" drive socket wrench in the old plug? I've never had a problem with mine.

79nautique wrote: use this if you are using your dremel tool cut an x in the head and then use your cold chisel to pop them off the rest of the way if you cannot get to it to cut it off perpendicular to the thread body.

Hey All,
Can anyone show me what this tool is? The link does not work. I am running into the same situation. I need to get a couple manifold bolts off.
Tom