Thermostat Cover Screws

[Wigwam]

 :2thumbup:  :yow Hello gang, I hope for those who celebrate such things, y'all had a Merry Christmas, and for ALL I wish a Happy New Year.

I committed a real rookie mistake; I over-tightend one of the screws on the thermostat cover, or at least I believe I did.  I am unable to remove the bolt in question, it just spins.  I know that I didn't snap-off the bolt, but I do suspect that in my zeal to tighten it, without a torque wrench, I broke the adhesion between the brass nut and the plastic radiator housing that held the nut in place.

The radiator is in fine to very good condition and I 'd prefer not having to replace the entire bloody radiator because of my knucklehead move.

Once I realized I couldn't unscrew the bolt, I stopped wrenching on it, lest I make matters worse.

Any suggestions or experience on the remedy?

Should I simply extricate the brass nut from it once secure place in the plastic and dremel tool the damaged hole and epoxy the nut back in place?

Thank you in advance for not laughing too loudly AND for any insight you can share.

Regards,

Wigwam
aka Joseph Youngblood :mbird

[The Mighty Gryphon]

Not sure how you should proceed, but most epoxy has a tendency to soften at high temperature. 

You might want to visit a radiator shop with your old radiator.  These shops recore radiators by bonding the old end tanks to a new core.  They have something they use that is very strong and isn't affected by heat.  Maybe they can properly glue your loose nut back into the housing.

[Laitch]

Should I simply extricate the brass nut from it once secure place in the plastic and dremel tool the damaged hole and epoxy the nut back in place?

Is it a nut, or is it a screw? It is a screw. Try to stay calm and explain yourself so that others may understand. You epoxy that thing in place, how are you going to replace a thermostat?


You should be able to grab the screw with a vice grip or regular plier, pull back on it and wind it back out—slow and steady. Then insert a helicoil made for that size bolt. You're going to take a voyage of discovery. Google helicoil plastic.

[The Mighty Gryphon]

Laitch, I think he is dealing with a molded-in threaded insert that has broken loose.  The screw that holds the thermostat cover screws into that insert. 

I am pretty sure the boss that insert is in isn't large enough to securely hold a helicoil type insert.  There are adhesives that will get this job done, and I suspect the best will be found in a radiator shop and that is where I would go first.  They probably see this problem from time to time and will know the best way to fix it.

[Laitch]

Onward!

[Martin]

Possibly plastic welding might be a solution if the radiator repair shop can't help. Or a long shot maybe a Nut-Sert.
Regards Martin.