10 replies to this topic

[svvs]

Was doing fluids on the car today, and quickly realized I must have cross threaded my radiator drain plug to death this winter.

 

I got the plug out, but the threads are all filled with aluminum.

 

Has anyone ever re-tapped a koyo radiator?  I don't know if I should have a machine shop do that or order a fresh one.

 

Thanks,

Vick

[Jim Drago]

I have not, but I wouldn't think it would be a problem, just go up one size if you have room to do so. I don't think you need to buy a new one. 

Jim

[Bench Racer]

I hate that Koyo drain plug with c'bored hole for rubber washer, tends to make installing more difficult than without the rubber washer.

 

There are always options:

A. Re tap.

B. Have new spud welded to radiator

C. Weld closed/loosen lower hose to drain

D. procure new radiator

[svvs]

I ordered a new one because of my time constraints (no time during normal business hours to run to machine shop and getting car ready for test day for the devil in the dark), and also because this one is pretty blasted after 4 or 5 seasons.

 

I'll swap radiators, and then look into getting this one retapped or welded shut and using the lower hose from now on and keeping this unit as a spare.  Still a few NA's I'm friendly with running around here that may need a spare at the track.

 

Thanks for the reassurances guys!

 

-Vick

[Johnny D]

I would guess it's a NPT (pipe thread) and is tapered. But I guess you should find out.

 

No matter how bad you do it, you can use high temp Silicone and you'd probably have too anyway or teflon tape.

J~

[Bench Racer]

I would guess it's a NPT (pipe thread) and is tapered.

 

J~

The plug is not a NPT. Have the thread size marked some place, the bitch part of the plastic plug is the rubber washer. There is a metal plug made that I have the number for.

[Johnny D]

Eu tenho sua ficha corrido, o direito aqui 

J~

[Parity]

que????

[Johnny D]

Ya , translators crap.

 

"I have your plug Bench, I have it right here"

J~

[Bench Racer]

 

"I have your plug Bench, I have it right here"

J~

J, if you have some little hole that requires filling my plug would be to large, procure your small size here.

https://www.google.c...431.PdGNxtwoudI

[57T6Speedster]

Yes. retapped with a metric tap and used a stainless bolt instead...works great....doesnt strip now.