S370D Radiator Drain Cock Leak

[mntrails]

I changed the radiator fluid last fall in my S370D (original radiator) and was plagued through the winter with a very slow leak out of the drain tube that exits by the drain cock. When the weather warmed up, I took the drain cock out and found an O ring on the end that was old and compressed. That O ring has to seat and seal well for no fluid to leak through to the drain hose. I couldn't locate an O ring but was able to determine that the nylon draincock is threaded with 14 x 1.25 metric threads and that a Dorman replacement part no. 490-236.1 (drain cock and O ring) was only $3.50. I got my order in and it arrived today - looks like an exact replacement. While it would be possible to replace just the O ring, having a spare seemed like a good idea to me. Now that I have new one with a flexible O ring I can take off for comparison, I'll try to find the O ring size and post here for other's use as well. But if you need a replacement draincock, the part no. above should work assuming the Satoh used the same radiator in all their S370Ds. Interestingly, this drain cock is used in some Toyotas, Hondas, and not surprisingly, Mitsubishi's.

 

[oliver28472]

Readily available in parts stores.

 

[skylarkguy]

Thanks for the info...mine is doing the same thing.

 

[kdorsey]

I took the drain cock out and found an O ring on the end that was old and compressed. That O ring has to seat and seal well for no fluid to leak through to the drain hose. ...

Thanks so much for posting this.
Mine is pouring water from that drain - i was worried it was a water pump weep-hole of some sort and i would have to change the water pump.