Exhaust manifold removal

[runaway!]

I have an 86 F250, she smells stinky when I push ******* the go pedal. Checked under the hood and confirmed a leak somewhere underneath the manifold down to the first flange.

How hard is it to remove the pass side exhaust manifold after almost 25 years? Is this going to be a week long experiment with some Kroil and plenty of foul language?

 

[flareside_thun]

Most likely.....you might as well expect to break a few bolts during that task also. Soak her done real good for awhile then suck it up, pray to the IDI gods (Gary and Mel) and see if you can't get it done without issue.

 

[icanfixall]

What I would do is warm it up. then spray it down well with arekroil. Kinda make the kroil cool it down. Do this and let it sit overnite. Do it again the next day too. Then warm it up and try to loosen each bolt one at a time and either remove and coat the threads with antisiez and reinstal or just remove them. But doing one at a time till you know that they all are free is a good thing. These are a special interferiance thread bolt. Ford still sells them too. Look for any black soot. thats a crack or a gasket leak.

 

[runaway!]

Thanks for the info, I'm guessing when you say heat it up you mean run it? Is this something I want to do with a torch?

 

[GenLightening]

I didn't have any issues with either the 7.3 or the 6.9, all came off easy. Unlike the 400 that I broke almost every bolt...... That was a long night.... Thank god for my 90* drill!

 

[Dieselcrawler]

I to never had an issue. But I loosen them after driving the truck and with it still running.

 

[icanfixall]

No torch needed. Just the runing of the engine till warmed up will work. Useing Aerokroil is the best thing you can use. Find them on the net and read the warranty... You buy 2 cans and if it does not work or your not happy send back the full can and keep the partical can plus a full money refund.... Thats a super deal... They are listed under the heading... Kano Labs..

 

[runaway!]

I know kroil very well, it has been a life saver at my job. Haven't used the aerokroil though, just the standard tin can kroil.

Thanks for the advise!

 

[lindstromjd]

When I just did the heads on my brother's 84, the manifolds had never been touched as far as I know. Every bolt came off clean and easy with a box wrench and a breaker bar. And this was with a cold engine, too.

 

[FordGuy100]

Mine came out no problem either.

 

[redtop_travis]

Mine came right out. The bolt heads were rusted almost gone. They will strip before braking for sure. Easy project just remove the inner wheel well to make it really easy.

 

[Danielle]

I love when someone asks my question for me hee hee

 

[whiteboyslo]

Not that you need one more 'me too' here, but when I did the exhaust manifold on my 351W, everyone and their brother told me I was in for a world of hurt with broken bolts and studs. So, every day after work right when I got home, I sprayed the bolts down with PB Blaster (didn't know about Kroil at the time). I did this for two weeks. Probably overkill, but when it came time to do the job, they all came out with zero issues.

Mike

 

[GOOSE]

As you have seen, the success rate for this job is pretty high. I have had to remove manifolds on 3 different engines and had no issues. Every one was on a stand and no spray was necessary.

I too had nightmareish memories of taking the manifolds off of my 390 and breaking numerous bolts. What is it about diesels that allows them to defy the odds compared to the gas engines when it comes to this?