Am trying to get the connector off the return transmission line on my 89 240 I want to flush trans fluid but cant get the dang nut loose Tried ye old bp blaster. Tried a little heat. No go I'm afraid I'm going to snap it. Any suggestions for taking off a 14 yr old nut. Thanks for all your help Phil

Keep hitting it with PB Blaster (can't think of anything better), perhaps also a little heat from a very fine flame torch (but not with PB Blaster residue left, or boom!), and *especially* be sure to use only a flare nut wrench as a tool!
When I first did this myself, the nut kind of gave way suddenly, like it "snapped", rather than a gradual give way. Took a lot of effort at first. Made me think some sort of sealant (thread-lock) had been used.
Good luck.

Rather than taking a chance on damaging the radiator, I'd cut the return line ahead of where it connects to the radiator, do the flush, and reconnect with rubber tubibg as suggested earlier. As an extra, you could splice in a filter to keep the tranny oil clean. IPD sells them. Don't saw the metal line, use a tubing cutter for a smooth cut.

You can always cut the line away from the radiator a few inches with a tubing cutter, then use a piece of high pressure fuel line and a couple of hose clamps to splice it back together. Or use a compression union fitting.

Good idea from JimL.

If you use the compression union, get a 5/16" ID one — about $1.50 at any good hardware store. I've used them to splice in 5/16" copper tubing to replace leaky sections. Also fuel lines on older kjet cars.
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Bruce Young
'93 940-NA (current) — 240s (one V8) — 140s — 122s — since '63.

Thank you, thank you, .... please hold the applause

Use a crescent wrench or something to "counter-hold" the larger hex where the fitting meets the plastic radiator tank. Especially if you're going to be smacking on the smaller wrench (time for a 3rd hand).
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Bruce Young
'93 940-NA (current) — 240s (one V8) — 140s — 122s — since '63.

Heat it up some, put a line wrench on it and give it a sharp smack with a hammer and be prepared to buy a new line and or radiator if it does not work. You can slowly twist a tight line fitting like that into a worthless candy cane, but if you give it a sharp smack often times you can get it to pop free. It is the difference between a breaker bar and an impact gun. You are impacting it instead of slowly rolling the pressure on. Good luck.


Rule 308