Just bought a rusty Jan 69 intake manifold for my car. It was a $120 (shipped) eBay find with all of the fittings still on it. Managed to get all of the fittings off without damage, with the exception of the temp sending unit. Used PB Blaster, heat and cold shock; still nothing. Now I've got it sitting in a pan of evaporust to try dissolving the rust around the threads and get this last fitting to come loose. I've chased all of the other threads, and scraped the gasket surfaces. Under the coating of greasy rust, that intake was pristine; a diamond in the rough. I'm waiting on the various techniques to yield some progress, not get impatient and screw it up.
Figured there were some other gearheads who have been here before and can appreciate the struggle. Don't get angry, don't force it. Let the tool do the work.
John
John
To err is human. To really foul things up takes a computer.
Been there. I made use of a 5 gallon bucket that used to have about 100 pool chlorine tablets in it. Filled it half way with Purple Power cut with some water. I would just drop in greasy, cruddy brackets or engine parts and then let them soak for about a week.
When the parts came out there was no grease, no crud, and usually no paint left. Ready to refinish.
Best way to deal with it is to have other tasks lined up that can be completed in the meantime.
2012 Mustang Boss 302 #1918, Competition Orange. FGF replacement 2006 Mustang V6 Pony, Vista Blue. Factory ordered. 2019 BMW X3 (Titled to the wife, but I'm always driving it for her. So I'm claiming it) Old projects, gone but not forgotten: 1967 FB 400, original CA car. After 22 years of work, trashed by the guy who was supposed to paint it. I had to sell it. 1980 Turbo Trans Am 1970 Mustang fastback, 351C 4Bbl, auto 1988 Mustang GT, 5 speed 1983 F-150 4x4, built 302 1994 Chevy K2500 HD 4x4, 454 TBI
Used heat on the manifold and inverted the canned air to get liquid out. Sprayed the liquid into the sending unit body (it was already broken out) for the thermal shock. Sitting in evaporust overnight for the next phase of effort.
John
To err is human. To really foul things up takes a computer.
You have more patience than I. I had a sending unit stuck. Heated, cooled, soaked, lubed, nada. Then I drilled a hole through a six point socket, put the socket over the SU, using the holes in the socket, drilled through the su, hammered a steel pin into the socket/sending unit, bolted the manifold to a piece of 8X12 Fir, put a breaker bar on the socket and using a long snipe started too apply a lot of force. Broke the manifold, bought a new manifold. Nothing to it, piece of cake!
Another trick is to cut it off, if it's brass this is easy, if you can open the center to get a small/thin sawzall or similar blade in there and cut perfectly level down towards the threads, do cut into the threads of the manifold just the fitting, and go slow and easy, as you get into the threads of the fitting you can try snapping it from each sides of the cut with a punch and hammer, it should snap and collapse, making the diameter of it smaller and it will simply unscrew by hand.
The hex-head sending unit housing started to collapse, so I have been at it with a pipe wrench. Still no damage to the intake at the moment. I'll see if I can get a picture.
John
To err is human. To really foul things up takes a computer.
Been thinking about this some more. You temp sensor is located such that the sensor is directly in the water. The fitting is a plumbing pipe fitting meaning the thread is tapered. It would only need ~20 ft lbs to tighten a plumbing fitting. So why do we need so much torque to get it off? The corrosion is on the inside of the manifold. When you try to take it off your pulling the corrosive metal fragments that are coated on the pipe threads up and out the female connector. It won't let you do it. The long and short of it is, I recommend having the intake put in acid bath (tank it Dano!).
Tell em you want the fitting off. They will know how to get it off. If your having that much trouble getting it off then the guts of this part could be very poor. Tanking will destroy it or fix it. If it's weak, let it fail now.
Each one of you have been giving great advice and I've been doing much of what you've said. I submerged the front end of the intake in evaporust. I am very impressed at its abilities and now I'm waiting on the PB Blaster to work for a day into those threads. I think the corrosion beyond the intake-fitting interface has been cleaned away. I am determined that this intake survives. It cost $120 shipped! Nobody touched it because it wasn't pretty. All of the threads have cleaned up and the fittings I got back were still usable (aluminum thermostat housing, thermostatic vacuum valve, PCV elbow, and the air breather vacuum fitting) with the exception of the sending unit. I'll post pictures of my mini-saga soon as I have them. Looking forward to completing the next step in getting my bird back on the road. The battle is worth it.
John
To err is human. To really foul things up takes a computer.