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Nut that holds HVAC box to firewall spins but won't climb threads
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go hereXJ (84-01)
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Nut that holds HVAC box to firewall spins but won't climb threads
I am unfortunately having a lot of difficulty with my heater core/evap project, and this is another obstacle I have to overcome. I have been turning this bolt 1/4 at a time for the past 15 minutes and it does not appear to have budged at all. I can't spin it freely with my hand. I tried to put a screwdriver behind it and turn it with the wrench so it would grab the threads. This resulted in me dropping the wrench somewhere behind the engine and maybe on top of the transmission?... Not sure, but RIP wrench because I can't find it anywhere
try using a magnet tool that expands and retrieve wrench; and when I removed my heater and ac box I had to remove it from the inside ; I had the same issue; the bolt through the firewall just spins and it’s made to unscrew from the housing but the stud remains; just try to loosen all of them even though it feels like they aren’t coming off; eventually the whole unit can be pulled out
Soak in penetrating fluid. I'm thinking spray every 15 minutes for a couple of hours and once a day for a few day. If you don't have time, then use a nut splitter. A cold chisel would be a poor man's nut splitter.
Use a set of locking pliers to hold the bolt while you unthread the nut. Add two nuts towards the middle to creat a jam nut. Hold the inner jam nut with one wrench and in screw the rusted nut with another wrench.
All of these including possibly the nut splitter would be benefited by a good penetrating fluid.
P.S. a smaller hand may be able to fit around the transmission. A quick acceleration, then deceleration in the driveway may free it as well.
Soak in penetrating fluid. I'm thinking spray every 15 minutes for a couple of hours and once a day for a few day. If you don't have time, then use a nut splitter. A cold chisel would be a poor man's nut splitter.
Use a set of locking pliers to hold the bolt while you unthread the nut. Add two nuts towards the middle to creat a jam nut. Hold the inner jam nut with one wrench and in screw the rusted nut with another wrench.
All of these including possibly the nut splitter would be benefited by a good penetrating fluid.
P.S. a smaller hand may be able to fit around the transmission. A quick acceleration, then deceleration in the driveway may free it as well.
^^^^ This is what I'd do. If I got super frustrated with it, maybe take a dremel to the nut, cut it as close to the threads as you can without buggering up the threads and then split it with a chisel or big screwdriver.
I tried the knife blade but wasn't able to get any leverage to get it on the thread. I ended up borrowing a precision flathead screwdriver and putting it behind it to gain some leverage. It took more tries than I'd like to admit, but I got it eventually.
03-20-2019, 02:03 PM
Nut that holds HVAC box to firewall spins but won't climb threads
