WESCH

Hi
I'm trying to remove the steel water fitting from my 68 big block alu intake.
It's the fitting for the heater hose which I don't need anymore.
I like to install a clean plug.
So, this ugly steel fitting is corroded and very tight. I'm afraight to break the alu intake.
Any ideas ?
Thanks Gunther

Smokehouse69

I hope somebody does have an easy solution for you or a trick for you to try and get it out. I would try cleaning as much rust as possible from the upper threads of the fitting and then apply penetrating oil to those threads, and hope it will soak down into the aluminum manifold.
Also a few light taps on each side of the fitting might help break the rust loose so the oil can get down into the manifold. After a couple of days of this treatment, try removing it again.

Tom454

I had the same problem with a GM SBC aluminum intake... and I cracked the intake. Had to weld the crack and then fill in the entire hole.

On occasion, due to bonding of the rusted fitting to the corroded aluminum, an aluminum thread will break off from the manifold and remain embedded in the thread groove of the fitting. Then, as you try to turn the fitting out, the aluminum threead peice is carried outward with the fitting... the added thickness of the aluminum chunk in the fitting thread groove causes the manifold to crack.

So... be careful & take your time. I was using a 1/2 breaker bar & a socket when I broke mine.

Tom

john's '81 mouse

Clean and soak for a few days using PB Blaster, this stuff really works!

Get a six cornered deep socket, and use extension as required to use air wrench to jar the fitting loose. Don't use the strongest setting on the air wrench at first, start with light setting and work to a higher one to avoid stripping out or cracking manifold.

jackson

You see what happened to TOM. That's likely to happen here too. I'd wait to do this until you're ready to remove the intake ... and can more easily have it welded shut when it cracks. Until then, cap it off with a piece of hose and a plug. Nobody'll know but you ... & everyone else that've read this thread;) G'Luck & Happy Holidays.

BSeery

I had similar problems twice when working with the bolts on the thermostat housing.

NOTE TO ALL: USE STAINLESS STEEL BOLTS ON THERMOSTAT HOUSINGS !!

I swear, every car I have bought with an aluminum intake had some dork install the housing with steel bolts. The bolts get bonded in, break, and then you break an "EZ OUT" (EZ OUT MY AZZ!!) trying to get the bolts out. Next thing you know, your pulling the entire intake and getting a new one at a swap meet, or having your's drilled out at a machine shop.

STEEL+ALUMINUM+WATER=WELDED !!

Anti-seize helps some, but the best way is to use bolts / fittings that won't rust !!

DAMN ELECTROLYSIS !!

bn7035

I agree with the others, wait until you can take the intake off, just plug it off. One idea that worked for me once when the darn thing broke off just above the threads was to take a hack saw blade and cut it out in sections. Saw very carefully until you get to the threads. Take a small chiesel and gently punch out the sections. Kind of like cutting a donut into 5 or 6 sections from the inside out.
I would only try it as a last resort. I've never heated aluminum. Has anyone else tried to heat up cast aluminum with a torch or is that a no-no

Paul L

That's a tough one since the intake is on the car. I took this one out about a month ago but used penetrating oil on both sides. In that that intake is so rare I would soak with penetrating oil for three days, twist with a hand wrench gently (or gentle persuasion) to break the metallic/corrosion bond, out one or two threads once done, hit again with oil, and continue patiently.

chowguy

if you dont know how to heat alu dont it does not change color it just melts.like solder.your best bet is to spray oil it for a couple days then try to break it lose. if that happens dont try to turn it out all at once work it out back in forth in & out with lots of oil take your time

Pete79L82

I would not heat the manifold.

What I have had good luck with is to heat the fitting, keeping as much heat away from the manifold as possible (even use a wet rag wrapped on the manifold) then let the fitting cool completely. Then attempt to remove the fitting.

By heating and then cooling the fitting it seems to break the corrosion bond between the two parts to aid in the removal.

This trick works well on bolts in aluminum also.

Tom454

Lots of good suggestions.

I can provide a little more input since I have done this... more than once.

The fitting is easiest to remove when the manifold is still bolted to the engine. The reason is, the torque required is usually pretty high, and holding the manifold while you unscrew the fitting is pretty tough. When it's bolted to the engine, the engine holds it for you.

I have purposely re-bolted intakes to engines specifically for this task.

Second, I weld aluminum with oxygen/acytelene using a welding alloy called "Lumiweld". It works fine as long as you follow the rules.

Aluminum takes a lot of heat to melt.... a hand held propane torch cannot produce enough heat to do damage because an aluminum manifold is a tremendous heat sink. It is pretty difficult to weld an aluminum manifold using gas for this reason.

Just last week, I removed a broken/rusted water outlet bolt from a 1980 GM aluminum intake using oxy/acyt and it worked fine. As posted, it seems to work best when you heat the fitting/bolt etc. rather than the aluminum, although I do heat the surrounding aluminum evenly at the same time.

Cutting it from the inside, being carefiul not to cut into the threads is another good way to do it... assuming a low klutz factor.

One final note... you can cause a "porosity" problem when using gas to weld an aluminum intake. 50/50 chance. Propane may be okay. You cannot use propane to heat an aluminum manifold up hot enough to weld it due to the manifolds fast heat dissipation.

FYI
Tom

UKPaul

As above. What I did on mine (& what usually works with steel fitings in alloy) is the application of penetrating oil, heat & lots of patience. Heat the fitting with water still in the manifold. What you're trying to do is get the steel to expand while the alloy doesn't. Then pour lots of cold water on the fitting to suddenly cool it. Try this several times. The idea is that by expanding & contracting the steel several times the seal between the two may be broken. Then do it the other way round, but drain most of the coolant from the manifold. Use a propane torch to heat the manifold around the fitting (it won't melt with Propane), bringing both the manifold & fitting to the highest temp you can. Now the tricky bit, by using a bit of rag in the fitting carefully pour water into it to rapidly cool the fitting & not the manifold, to rapidly contract the steel. It may be loose enough to remove after this treatment. Pouring penetrating oil copiously around the threads while applying the heat will also help (if a small gap opens up during the expansion phase the hot, thin oil will get down into the threads). The oil will make a real mess. Also giving the flats on the fitting some well placed sharp taps with a hammer (not heavy blows, just sharp sudden taps from alternate directions, although heavy blows are tempting!) will help. Trying to tighten the fitting may also help free it up. The most stubborn case I ever had needed extreme heat to solve: I used an arc welder to weld a bolt to a rounded bolt head in cast alloy. The extreme heat broke the joint free & a normal wrench undid it with barely any force.
If it won't come out then remove the manifold & mount it on a drill press. By using a drill of the right size ACCURATELY down the centre of the fitting you'll end up with a spiral of steel in the manifold which should come out with a bit of fiddling with needle nosed pliers, etc, depending upon what you can hold with your burnt fingers :D Or you could ask a friendly Engineer to spark erode it for you, but get a cost quote first (can be expensive).
Good luck & have a fun weekend!
Paul

WESCH

Thanks so much for all.
I will try with heat as suggested, but will not use too much brutal force. I don't want to snap off the Alu intake's end piece.
This fitting is soaking sinse 2 days in Kroil ( penetrating oil used in Airline business ) .
If this damn think doesn't come loose by itself after I return from church :nopity , I will leave it where it is till the intake comes off for an other reason.
Will let you know how I destroyed this nice alu intake. :reddevil
Thanks Gunther