Plaineman

I am having a hell of a time getting the exhuast manifolds off my 2000 7.4... Corrosion is really bad and I already broke a couple of bolts... is there any special penetrating fluid or even something that might just disolve the heads of the bolts? I dont even care what happens to the monifold as I have to change them out anyway.

Any suggestions would be greatly appreciated.

MOBILEMERCMAN

get a selection of under size 6 point sockets like 13mm, 12mm, and maybe 11mm. Hammer them on.

Plaineman

Yeah... I only had those in inch sizes... I almost got a 3/8 on there but it wouldnt grab.

Bryan Rose

PB Blaster available@ napa

Plaineman

What is PB blaster???

Bryan Rose

the best penetrating lube there is $5 a can spay it on wait about 2 hours or so and go to work on it , this shi!! Really works

offthefront

iTrader: (1)

PB Blaster wont help rusted head bolts ....The heads are just rusted up and fall apart when you try to break em loose .... when you get the bolts out you will see the threads are fine ... We just did one this week and used an air die grinder with a carbide steel bit and ground the heads off ...the manifolds will come right off and then the bolts will turn out by hand ... one note ..... try to cover and catch the metal fillings ....If you can position a shop vac as you grind will help .... The Fillings will rust .....m

MOBILEMERCMAN

Try the sockets first, grind at last resort.

mcollinstn

Kroil, in my opinion, is better than PB blast. Shoot wha you can with Kroil, then add head (torch or heat gun), and then put an air wrench on it on LOW and let it sit there and hammer on it. The hammering works the Kroil into the cavities, and the heat helps too. Then add a new shot of Kroil and come back the next day. Sometimes it helps to come back on the next day and if they aren't willing to come out, add more Kroil and use the air wrench set to TIGHTEN. This works the lube into the opposite side of the threads.

If that fails, then go ahead and muscle the heads of the bolts off. Once you get your manifolds off, shoot more Kroil in and keep trying.

If you get close to the block, then you can use the failsafe method of removing the remains of the bolt.

1) grind the bolt flush with the block
2) add kroil
3) find a washer with a hole just a TOUCH smaller than the bolt diameter and drop it onto the bolt
4) Tig weld the washer to the bolt, directing the heat mostly into the broken bolt.
5) weld a NUT to the washer.
6) hammer on it a few times
7) throw an air wrench on it set to medium and zap it out.

The Kroil, the HEAT from the welding, the expansion of the bolt due to the heat, the hammer impact, the shrinking from cooling off, all of that breaks the HOLD on the bolt. It should zap right out with the air wrench.

This works on ANYTHING that is broken off in cast iron.

Mc

Plaineman

Thanks guys... I did realize that I could just grind off the heads of the bolt but I am trying to avoid. The engine is still in the boat and it's a little tough to get in there but I will get em off. Thanks again and happy boating to all of you.

B