Archived radiator will not drain

[DrJC]

In my '96 turbo-diesel, I'm attempting to drain radiator to change coolant. Have turned plastic petcock 1/4 turn left. Nothing. Have repeated moving petcock back and forth between stops in a 1/4 cycle, without success.



Have also attempted to probe with a thin metal, but the passageway seems solid.



What would you suggest? Appreciate your help.



Dr JC

Michigan

 

[DHayden]

Did you take the radiator cap off? Sometimes people forget

 

[DrJC]

Hayden,



Yes, I did remove the radiator cap. Also started and warmed the coolant with the cap on to pressurize the system. Still, nothing drains via the petcock.



I'm wondering if I could pull the part of the petcock that turns out of the assembly. Of course, I'm reluctant to try for fear of destroying it!



Thanks for your response.



Dr JC

 

[Jefff929]

When I pulled the rad, I had better luck pulling the lower rad hose just enough to get a stream in the bucket.

 

[LandShark]

You must also pull the plug out while turning. As I recall, it will come out about 3/8 or 1/2". It's OK to pull it all the way out; that way you can inspect the o ring.

 

[Skydiver]

It must be hard water got it stopped up. I always pull the bottom hose enough to get a nice trickle.

Tip- After you flush the system catch some of the liquid in a clear glass and hold it up to a light. Might be surprised at the solids. Never add hard water to anything except a mouth. Distilled water is still less than $1. 00 per gallon.

 

[DrJC]

Thanks a lot for the responses, fellows. The key was in also pulling the plug outward as it is being turned.



It was very frustrating up until that point.



Job done, thanks to you and this forum.



Dr JC