I want to drain my 2006 PT radiator of old coolant MYSELF & replace with fresh coolant.
Not a flush, not super thoroughly drained, just whatever will drain & replace with fresh.
Any reason to expect any problem loosening & removing the coolant drain **** / plug?
It's been in place undisturbed probably 12 years. I thought I'd spray some WD-40 or similar on it, let it soak in.
Any dire warnings or concerns that it's fragile, it'll break, don't take the risk, do something else?
Or no sweat, it does what it's supposed to do, no problem, go for it ?
Thanks much for any input or relative comments.

 

Assuming the old rubber gasket is worn-out, liable to leak on reinstallation...
Maybe I'll have a fresh drain **** / plug handy to reinstall.

 

Has the coolant not been changed in 12 years or just the plug not removed in 12 years?

If the coolant hasn't been changed in 12 years, I would say you would need a full flush as that radiator will be full of a lot of crud and the interior heater matrix as well.

If it has been flushed out previously by pipes being removed, I would say just unclip the pipes and let it drain out that way, you will drain out a lot more then as well.

Also if it has rotted into the grooves it screws in, you may find that once it's removed, it won't go back in properly and you may end up possibly needing a new radiator but that is the very worst case scenario and unlikely.

In my opinion, I would just unclip the lower pipe and let it drain out that way and give it a dam good flush out with some distilled water, I wouldn't use a radiator flush product as they can cause more issues at times. Also if possible consider backflushing your heater matrix at the same time, will make a world of difference for heat in the cabin.

 

As for coolant & draining / flushing history, I have no idea, I've owned it only 2 years. I bought a new drain ****. Given the local temperatures here in N. IL, I reconsidered DIY & I took it to a local NAPA shop. I specified drain & refill only. The drain **** was loosened just enough to allow the radiator to drain. When drain was complete, the tech was reluctant to completely remove & replace the drain ****, as he said sometimes bad things can happen. He re-tightened the drain **** & it didn't leak after fresh antifreeze refill. Process took 30 minutes (really less), I paid 1/2 hour @ $105/hr shop rate. Just FYI, I plan to sell this PT next spring, I don't want anymore investment than necessary. I'm feeling better about its ability to handle winter now.