Good day to all and happy wrenching!

I was flushing my coolant system and I tightened the radiator drain plug too tight. I have a '93 850. When I tried to loosen the drain plug it just spins. I am wondering how this situation can be remedied. Is it safe to HeliCoil/tap a new hole in the bottom of the radiator if the threads are damaged in said radiator?
I haven't taken the drain plug out yet so I don't know if the threads in radiator are damaged or not but...the good part is that it doesn't leak...

So I guess others can benefit from my mistake and be careful not to tighten the petcock/drain plug too tight on the radiator. Thanks for all the great posts here, they have helped me much and will continue to do so!

jeff

 

Hi Jeff,

Sorry about the problem.

Try loosening the plug while pulling down on it. If it comes out this way, you can insert a new drain plug. Or, if there is a slight gap, see if you can insert a small flat-blade screwdriver and gently pry it & turn it.

The drain plug is easy to break off, been there & done that myself. When you tighten, finger tight + 1/8 turn should suffice.

This is the best I can do with my sleep-deprived, stressed out brain.


JPN

 

Hey now,

If it is not too bad and you can get it out, maybe some silicone tape on the threads may help .

Please remember that the cooling system is a preasurized system and if the threads are as bad as you describe, you may have no alternative but to replace the radiator [:@].

Let us know what you find/decide.

[sm=icon_cheers.gif]

 

Thanks for the replies. I will let you know what i find out. I will work on it tomorrow. I appreciate the point about the pressurized nature of the cooling system.

 

The drain plug is installed in the resin portion of the radiator and the plug is either of the same material/plastic. You could still try epoxy and permanently seal the radiator, after draining the radiator. Then you can fill it with 10-year/100,000-mile extra-life coolant. Worth a try before spending $200+ on a new radiator.


JPN

 

Or you can use regular strength coolant and flush the system by disconnecting the lower hose.


JPN

 

I NEVER use the damn petcock if I can help it. In the past every car I have had that I used the petcock ended up with it leaking. I drain the coolant by pulling the lower hose like was posted earlier. As for the petcock, if it is not leaking, leave it alone and use some epoxy (JB Weld on it when you get the chance. Just my .02

 

And in case if epoxy fails, you always have the ultimate solution to fall back on; DUCT TAPE + SUPER GLUE COMBO.


JPN

 

Thanks for all the suggestions. It's not leaking and I ordered a new drain plug. Maybe I'll just bypass the drain plug alltogether and leave it, using the lower hose like you say. THat seems to be the best solution for now. Thanks a bunch, really...I love this forum!

jeff

 

Good luck and let us know if you have any more problems with it

 

Somehow the drain plug/petcock came out of my '93 940 wagon the other day on the freeway, fortunately I made it back home w/o things getting real hot. However, after visiting a Pick N' Pull in my area the only car I could find that still even had a radiator with a drain plug was an '87 240, which I removed. After doing a web search, from what I can tell, it looks like the same thing, but now, I can't seem to get the treads to "hook up" so I can turn the thing. Do different early 240 series Volvos have different drain plugs? Or could there be some other issue with my radiator that would cause the thing, first of all to fall out, and now making it difficult to re-install?

 

 

Never mind....I was able to tap it a little and get it going. But now it seems like the threads are stripped for some reason, so I guess I'll default to the super-glue fix and simply remove the lower hose to drain the radiator from now on. It sure is nice to have all of this great info on this things available. Thanks so much!

 

Thanks, but unfortunately it's leaking. I must've damaged the threads or something when I drained it to do the water pump a couple of months ago. Your hose fix sounds like it might work, except how thick of hose are we talking about and are you saying that you wrapped it around the drain plug or what? I could see something the thickness of an inner-tube maybe used that way, but I'd like a little more clarification on the fix you're talking about with the hose please.

 

 

Yes, I wouldn't mind seeing what you did, if it's not too much trouble. As it stands, I stuffed a bunch of head gasket sealer into and around the fitting itself, but am going to let it set up for 24 hrs to see if it helped.

 

 

Hey, if it works..... However, I'm not going to bother with using the drain plug anymore and simply find a way to plug it up for good, if the H.G. sealer doesn't work permanently. Thanks again for the help!