seized shroud screw in Clark oversize tank

[jostby]

I bought a used Clark oversize tank and it came with one screw seized in the metal thread base thingy (how's that for a description?) It is the screw for the right side radiator shroud that would be hid by the seat. Has anyone dealt with this? I'm not sure whether to just cut it off flush and live with it or try just a little harder to twist it out. It is a stainless screw and looks like the insert might twist out off of the tank before the screw breaks. I don't want to ruin the tank. The shroud would probably be OK with just the forward screw holding it (plus the one radiator mount screw). It has been soaking with "Liquid Wrench" for a couple weeks and no change. Any ideas?
Thanks,

 

[widebear]

Drill a small hole through the head of the bolt down into the lenth of its shank. That will relieve alot of tension. Should come out after that.

 

[roostafish]

I hate dealing with this stuff, I can sympathize. Liquid wrench is good, but if it's been two weeks.... This is what I'd try before cutting it off. Put some premix gas on it. I recently picked up an XR 80 with a siezed piston, from corrosion and elements, not engine failure. I soaked it in Maltby, then light weight machine oil, then WD 40. Two weeks in the making, and still no budge. Then I filled the spark plug hole with premix and let it sit for a couple of days, refilling once. I grabbed the breaker bar and tweaked on the flywheel again.... Squeak! It broke free, and has been free and smooth ever since. It's a longshot, but gas is very very thin, you may try it.

 

[carlg]

If all of the above fail here's another couple options. Try drilling the screw out with the correct body drill size for the tapped hole. Then chase the hole with the tap, you may still have enough thread to serve the purpose. If that doesn't work see if you have enough material left to go up to a larger diameter screw. Or another option might be a heli-coil thread insert which would allow you to keep the same screw that you're currently using. Many auto parts stores carry these. One last option drill out the screw and just get a self tapping screw, proably the cheapest way to fix the problem.

 

[jostby]

Thank you, all good ideas but keeping in mind the screw is stainless, drilling probably won't be an option though I haven't tried it yet (stainless is similar to grade 8, doesn't drill very well). The nut-zerts (type of heli-coil) would be nice but remember this is on the side of the fuel tank, I'm not sure how deep I could go before springing a leak. It's cold, I have 2 broken down cars (one is an engine on the wifes main ride) and about 3 months before I'll be wanting to ride again (read before the weather warms a little). I'm going to try to gas/oil trick and if that fails I'll try to drill the screw, I like Widebears theory. If drilling heats it up too much it will probably cause the nutzert to fall out (melt out) too. Keep the ideas coming
In all reality it would probably be fine to just cut it off and go without but I'm kind of a perfectionist and would like to not do that.

 

[carlg]

What a dummy I forgot that they make drill bits with a left hand helix, they will hopefully spin out the broken screw when you drill it out.

 

[JRDoz]

Does the screw stick out a fair way. Also does it have thread to the end of it.. Another option could be to saw the head off the screw and make a stud out of it and just use a nut..
If you have to drill it, get a bottle of cold water and pour when you drill. Keeps everything cool and use a sharp drill bit..