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Help with removing oil cooler lines from radiator

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Old 03-21-2009, 03:28 PM   #1
Brett Jenkins
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Default Help with removing oil cooler lines from radiator

I'm having an impossibly hard time removing these so I can replace/repair the radiator. Every way I try it, the entire line moves to the point of being bound and I don't want to damage it. I can't move the fitting on the radiator far enough to get it off, I can't remove the large 32mm end of the line from the next fitting, I can't remove the middle fitting from the line. Which piece should I be trying to remove, the entire thing from the radiator or the line from the middle piece./radiator. Which way should whatever I'm removing be turned?

Is the large 32mm fitting on the end of the line supposed to turn without the line turning and come off the middle fitting, or is it fastened together? Should it rotate like the large fitting on the air pump test port to the exhaust, around the metal end of the oil cooler line/pipe?
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Old 03-21-2009, 03:34 PM   #2
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You need to counter-hold with a 27mm on the radiator fitting.
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Old 03-21-2009, 04:00 PM   #3
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I'd tighten the fitting on the rad with a 27mm wrench and while counter holding use a 32mm wrench on the hose fitting to break the seal. Be careful with the cooler lines twisting.

You may need to pre-soak the fittings with suitable liquid.

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Old 03-21-2009, 04:24 PM   #4
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The fitting on the radiator tank is one with the internal cooler. If you twist that while trying to remove the hose connections, there's a significant chance that the internal cooler has been damaged. Not a big deal if radiator replacement is in your plans, but if you repair it you'll want to check the integrity of the coolers while you have it apart.

The 27mm abd 32mm connections are common sizes for air conditioning hose connections, so you may want to look at AC tools to get the slim wrench for the radiator size. The wrenches come in pairs in those sizes, so you can fit them and just squeeze them together to get them to release.

The end of the hose fitting is normally fixed to the hose while the nut that holds it on to the cooler turns independently. There's almost always more friction at the sealing faces between the hose and the cooler fitting than there is between the hose and the nut, so the hose should not be moving if the cooler fitting is counterheld while the nut is turned. The only exceptions I've experienced have been the result of someone adding gasket sealer or sealing tape to the threads on the nut. There are special reserved words for people who do stuff like that. If it turns out that someone has blessed you with sealer there, and you know for sure that you are replacing the radiator, it's OK to use a good heat gun to warm the nut. If you plan on keeping the radiator, put water in the radiator before using the heat gun. It will take a lot longer to get the nut to expand free of the cooler, but you'll have less risk of melting or warping the plastic end tank.

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Old 03-21-2009, 09:28 PM   #5
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the 27mm fittings are screwed into the cooler after the larger Cooler outer nut is fastened. ( this nut fits flush with the radiator tank)
I think your problem is the cooler LINE nut is stuck onto the fitting that is screwed into the cooler so you need to counterhold it.
If that wont work cut the hose portion and work on the radiator out of the car. Use some PB blaster and if that wont work then use a torch on the 32mm nut and counter hold it with the 27mm wrench, wear gloves so you dont nick you hands

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Old 03-21-2009, 11:00 PM   #6
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Because of the tight fit, I took a large crescent wrench and ground down the sides so that it was thin enough to fit over the 32mm nut for counter holding and not crowd out the 27mm wrench. I didn't have an open end 32mm wrench on hand and this worked for me. This stuff is aluminum so careful counter-holding is essential.

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Old 03-23-2009, 12:13 PM   #7
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Finally got the radiator out. I heated up the large nuts on the oil cooler lines to expand them and they broke free with a little grunting. Thanks for the help and suggestions.
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Old 03-24-2009, 03:24 PM   #8
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The leaking end tank seems to be the seal, the plastic tank looks ok. Do I need to use any type of sealant with the new seal, or just put in the new seal and press on the end tank?
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Old 02-27-2011, 11:09 AM   #9
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To remove (and also tighten) upper oil cooler line to radiator, You'll need 27mm and 32mm wrenches (adjustable spanners are also ok, they are not that tight). First remove two 10 mm screws, what secures the radiator fan frame into it's position and lift it a little so that those srew points are free to move and push it to back 1,5 inches. Now You'll have enough room to counterhold the upper oil cooler nuts even with big wrenches. After tightening lift the fan frame back and voila. I've learned this lesson the hard way.
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Old 02-27-2011, 04:21 PM   #10
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FYI. old bicycle headset/bottom bracket wrenches are 32mm and our quite thin for the clearance.
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Old 02-27-2011, 11:24 PM   #11
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Do a search for a safe-ish way to remove&refit end tanks. As I recall, you bend the tabs open in a non-intuitive (but logical when you see it) manner - screwdriver tip inserted at right angles to radiator face into gap between tabs, press handle towards core face. You will need to cramp the whole assembly (as in using large carpenter clamps/cramps) to get the gasket compressed enough to seal reliably down the track. Biggest issue is usually having retaining tabs break off.
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Old 02-27-2011, 11:31 PM   #12
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To prevent the tabs from breaking you need to first anneal the aluminium.

Once annealed you can bend them up without breaking them. I then used a small rachet strap to hold the whole assembly together while working my way around the tabs.
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Old 02-27-2011, 11:31 PM

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