I am getting parts ready to replace the exhaust manifolds on my 1995 f150 5.0 with long tube headers because one manifold is cracked. Looking at the bolts I have to take off to get the manifolds off,they are VERY rusty. I can't really take the time to pull the heads off if I break a bolt off. what can i do to get the bolts out without breaking them? I know to use PB blaster on them,but what can i do for the threads in the head? the PB blaster won't get into the thread when they are at such an odd angle will it? thanks for any ideas,want to get this done as painless as possible!!

 

I have found if the engine is still able to run, take the truck out for a run and get the engine to operating temp.
Shut off the engine and while it is still hot loosen the bolts with an impact.
I seam to have better luck this way than when the engine is cold.
It it is still no guarantee that you will not twist one off.
For the header bolts heat them with a torch and while they are still cherry red take them off with an impact.

 

Spray them for a week prior to doing this job. The PB Blaster or whatever you decide to use, will penetrate down the threads of the bolt into the head. Heat is also your friend while doing this. Be prepared that you may break one off. It's not the end of the world. Get yourself some new cobalt bits and start drilling.
Once you get them all out, run a tap through the threads in the head before you bolt up the new headers. You may even want to go with studs.

 

Use PB blaster for a week and then try.

If the head of the bolt is rueted try a metric socket and make sure it fits tight on the bolt.

If it strips get the sockets that sears sells. It looks like a swearl inside. They work well.

If this dosent work grind the bolt head off with a 4 " grinder remove the head pb blaster the threads hit the stud with a hammer a couple of times and take the stud out with vice grips.

If the bolt is broken off flush you will have to use an easy out or drill and re tap it.

My 95 5.8 plow truck was so bad I had to do all of the above and remove the heads so I could get to the stude broken off flush to drill and tap .

I suggest you pull the engine.

 

I'd spend a few minutes heating and trying to remove the bolts if, and only if there is enough head to try with a six point socket. Using lots of heat, takes a while to heat a bolt running through the manifold, its made to dissipate heat.

For the most part trying to turn them is just a waste of time at that point.

If the heads are mostly gone or crusty with no hope of ever turning them with anything I'd just torch off the heads of the bolts.
Then I'd pry the manifolds off over the bolts, now "studs", and then heat them one at a time and use vise grips to remove the remainder of the bolts, the bolt flange of the manifold will help ensure you leave enough bolt sticking out of the head even with the short bolts to get a good bite with vise grips once the manifold is out of the way. Just be sure to only knock of the heads, no more.

About zero chance of snapping one off even with the head that way, I'd get em all no problem that way. No need to remove the heads, or remove the motor, no drilling and or taping to do the job.

 

If Bolts break off flush with the heads or even worse, snap off slightly onside the head, take a nut and mig weld it to the remaining stud, let it cool spray with penetrating fluid then get whatever size wrench fits that poor welded nut and slowly work it back and forth. Trust me it works great, did it to four pieces on my 95 F150, be patient and get a good hot weld on there, this may take multiple trys as the nut may spin off due to lack of fusion from the stud to the nut. but it willl work!!! saved me from taking my heads off.

GOOD LUCK!!!

 

thanks for the ideas. Does anything work better than PB blaster?

 

Cjben,
I went thru the same scenario with my old 86' F350. There a lot of good suggestions that have been stated that all should work. Power blaster is very good stuff but, you must have patience. Give it at least 2 - 3 days of spraying the bolts to give it a chance set in and work. Also just in case here's a link to a very good article on the art of extracting broken studs ,bolts, etc...

The Art of Extraction

Good Luck!

 

You might want to read the Thread:
https://www.ford-trucks.com/forums/7...ting-oils.html
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