!$%$@ plastic radiator drain plug.
07-23-2006, 08:38 PM
#1
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!$%$@ plastic radiator drain plug.
Arghh.... just broke another one. This is the third one I've destroyed so far. I'm not going to touch the darn thing anymore -- I'll drain the radiator at the lower hose next time.
Has anyone ever successfully removed and reused that thing?
Has anyone ever successfully removed and reused that thing?
07-23-2006, 09:12 PM
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I'm just replacing it with a standard M10x25mm bolt -- metal on metal with water in there might cause problems, but at this point I'm not putting plastic back in. 
07-23-2006, 09:12 PM
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07-23-2006, 10:31 PM
#7
Originally Posted by josephsc
I'm just replacing it with a standard M10x25mm bolt -- metal on metal with water in there might cause problems, but at this point I'm not putting plastic back in.
For broken plastic plugs, try this. Shove the head back in the hole and rotate it till the the lands and grooves lock into the threaded portion. If it's broken off smooth, this won't work. You've got to press in fairly hard, but it's possible to press and turn slowly, and be able to back the threads out of the hole.
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07-23-2006, 10:41 PM
#9
Hey Man
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Originally Posted by josephsc
I'm just replacing it with a standard M10x25mm bolt -- metal on metal with water in there might cause problems, but at this point I'm not putting plastic back in.
07-23-2006, 11:11 PM
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Many make the mistake of trying to torque the plastic plug down. This is not necessary. It's the o-ring on the shank that makes the seal. The o-ring and the pressure build up in the radiator is what seats it in the groove and promotes it's sealing. All that needs to be done is to snug the plastic plug down against it's funny looking lock washer. Replacing the plug with a bolt can ruin the drain hole walls. The head of a bolt and the flange on the side tank are not intended to be sealing surfaces. When you jury rig your car you are becoming the SOB PO.
07-23-2006, 11:38 PM
#11
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Ironically, I was being really careful with putting the darn thing on (since I've broken two before). 
Good info guys -- I appreciate it.
Unfortunatley, I need to jury-rig at the moment since I have another track day tomorrow morning. Plus, I'm practically married to this car (this is the 944 that I've put in ungodly amount of time into), so I don't have worry about become the SOB PO. It does have to survive the 110degree heat tomorrow, however....
Good info guys -- I appreciate it.
Unfortunatley, I need to jury-rig at the moment since I have another track day tomorrow morning. Plus, I'm practically married to this car (this is the 944 that I've put in ungodly amount of time into), so I don't have worry about become the SOB PO. It does have to survive the 110degree heat tomorrow, however....
07-24-2006, 03:30 PM
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How are you breaking it? It does not take very much force to install. Has it every been touched before? Have you checked if your radiator plug threads have been crossthreaded?
07-24-2006, 05:02 PM
#14
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I tried the plug once on each of my cars. It came out OK on the two 944s and snapped on the 968. I think putting in a metal bolt is a really bad idea, especially when there are alternatives.
What SoCal Driver says is right - no torque is required on the plastic bolt. The two times it came off easily, it was because the bolt wasn't on very tight at all. The bolt on my 968's radiator snapped because it was on there real good.
Removal of the bolt shaft is easy: find a flat screwdriver whose head is smaller than the shaft diameter. Heat up the screwdriver with a torch, then shove it into the shaft remnant. It will sizzle it's way into the shaft, then eventually stop. It should have bored in about 5mm. Now you can just turn and extract the shaft.
Wrap some teflon tape on that shaft you just extracted, and put it back in. Mine's been OK like that for 2000 miles, I even autoXed and went on 3 fun-runs.
I just use the lower radiator hose now. A little messy but nothing breaks and it flushes out faster.
What SoCal Driver says is right - no torque is required on the plastic bolt. The two times it came off easily, it was because the bolt wasn't on very tight at all. The bolt on my 968's radiator snapped because it was on there real good.
Removal of the bolt shaft is easy: find a flat screwdriver whose head is smaller than the shaft diameter. Heat up the screwdriver with a torch, then shove it into the shaft remnant. It will sizzle it's way into the shaft, then eventually stop. It should have bored in about 5mm. Now you can just turn and extract the shaft.
Wrap some teflon tape on that shaft you just extracted, and put it back in. Mine's been OK like that for 2000 miles, I even autoXed and went on 3 fun-runs.
I just use the lower radiator hose now. A little messy but nothing breaks and it flushes out faster.
