720 Radiator Support Rehab

[DrvnDrvr]

I'm starting a rehab of my radiator support and would like to find a way to permanently modify the cooling system to drain the coolant without having it drain on the front crossmember. Maybe putting a petcock on the lower radiator hose. Maybe an extension of the existing petcock. I'm trying to preserve the paint on the frame.

 

Any ideas?

 

[Lockleaf]

 

I installed an adapter and then a brass petcock. I freaking hate how they designed that. A 5/8 hose fits over the exposed threads and I just put that in to a bucket to drain it.

 

This is on my '85 720.

[DrvnDrvr]

Thanks LL, just what I was looking for.

What thread size is going into the radiator?   1/2"?

What type of thread sealer did you use?

[Lockleaf]

I will get you that info (as best I can remember it) later today. The thread adapter I used wasn't actually the correct thread, but it was "close enough". When I threaded it all the way in it would tighten up pretty well. Then, just to be sure, I gooped the threads with rtv in addition to putting a copper crush washer on it.

 

That was three years ago or so and it hasn't leaked a drop

[Lockleaf]

Pretty sure it's a 3/8 to 1/4 "bushing" adapter.

 

I bought the stuff at O'Reilly Auto. Brand is edelmann. Adapter p/n is 210640. Petcock is p/n 349440. You will also need a hose barb or threaded coupler. They have a ton of options depending on how you want to do it.

[DrvnDrvr]

My petcock threads are fine and a standard 1/4"  won't fit . I'm gonna see if the mechanic at work has a metric die to make a thread adapter. My O'Rielly didn't have the right one. The radiator is new so I don't want to rinkydink it up. Thanks for the input.

 

[austenk]

1/4-18 or 3/8-18  pipe tap? If ya'll have a fastenal close by they will have the taps you need.

[DrvnDrvr]

radiator thread is metric. 1.75x 1.5 I think. I'll take it to fastenal as my work mechanic took the week off. Thanks