DeWitts Drain Petcock.
Thread Starter
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
DeWitts Drain Petcock.
So I finally installed my beautiful DeWitts direct fit aluminum radiator in my 1977. Everything went well. I replaced all the core support seals, and have plans and materials for the upper and lower seals.
I was leaning over the fender installing the lower rad hose, and my face's position put my line of sight run down the radiator filler neck. You know what I saw?
The day lit ground under the front of the car. I did a double take, because I could see the ground under the front of the car by looking down into the radiator.
It occurred to me that this was the location for the drain petcock. My first thought was that this could have been included with the radiator. My next thought was how much of a pain it was gonna be to measure and install it when I could have done it before the rad went in.
Then I began to wonder how many guys out there installed their DeWitts and started to fill with fluid only to see it all flood out on the floor. While funny, that would be a waste of distilled water and coolant.
So, share your stories and if you know off hand what size that drain petcock is, please enlighten me.
Thanks.
I was leaning over the fender installing the lower rad hose, and my face's position put my line of sight run down the radiator filler neck. You know what I saw?
The day lit ground under the front of the car. I did a double take, because I could see the ground under the front of the car by looking down into the radiator.
It occurred to me that this was the location for the drain petcock. My first thought was that this could have been included with the radiator. My next thought was how much of a pain it was gonna be to measure and install it when I could have done it before the rad went in.
Then I began to wonder how many guys out there installed their DeWitts and started to fill with fluid only to see it all flood out on the floor. While funny, that would be a waste of distilled water and coolant.
So, share your stories and if you know off hand what size that drain petcock is, please enlighten me.
Thanks.
Safety Car
Joined: Aug 2001
Posts: 4,883
Likes: 11
From: North Easton Mass
I'm not sure that I remember this correctly, but I had to buy a new petcock for my old radiator befire I bought the Dewitt's. I just took the old one to Autozone and had no trouble getting a replacement. If I did have to install a petcock on the Dewitt's it was most likely the replacement that I removed from the old radiator. At worst you could bring the radiator into the store and find a petcock that will fit.
Dewitt's is probably closed for the weekend but Tom often reads the forum so maybe he will respond with the correct size.
Rick B.
Dewitt's is probably closed for the weekend but Tom often reads the forum so maybe he will respond with the correct size.
Rick B.
Thread Starter
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
The crap part here is someone stole my old radiator out from in front of my house before I had a chance to take off the petcock.
I wish I could have seen that punk running off with that old radiator so I could yell...
"It's got a huge hole in it, good luck with it.."
I wish I could have seen that punk running off with that old radiator so I could yell...
"It's got a huge hole in it, good luck with it.."
Thread Starter
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
The ORIGINAL and bestest
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From: Toronto Ontario
Toronto Events Coordinator
I believe the threads are 1/4" NPT, any auto suppy store will sell those petcocks. I also believe Home Depot sells them, most air compressors use the same size petcocks. On a related note, I installed a 90* fitting in the bottom of the rad, then a 1.5" nipple, and then the petcock, which makes it much easier to get to when you are draining the rad and makes less mess because it is not draining onto the crossmember.
EDIT: changed 3/8" NPT to 1/4" NPT after checking.
EDIT: changed 3/8" NPT to 1/4" NPT after checking.
Last edited by 7t2vette; May 27, 2007 at 10:20 PM.
Thread Starter
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
I believe the threads are 3/8" NPT, any auto suppy store will sell those petcocks. I also believe Home Depot sells them, most air compressors use the same size petcocks. On a related note, I installed a 90* fitting in the bottom of the rad, then a 1.5" nipple, and then the petcock, which makes it much easier to get to when you are draining the rad and makes less mess because it is not draining onto the crossmember.
Awesome idea bud.
I was thinking along the same lines and was going to do that to the block drain plugs as well. That'll make flushing every spring easier.
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From: Toronto Ontario
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From: Brighton
All petcocks are 1/4" npt and each Direct Fit model is sapposed to have one included. We pack the petcock into the spacer box, which should be the first thing you see when openning the box. We pack it loose because 90% of our UPS damage was done to the petcocks sticking out the bottom. We figured if we packed them loose, they could no longer damage the valve or the radiator.
Thread Starter
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
All petcocks are 1/4" npt and each Direct Fit model is sapposed to have one included. We pack the petcock into the spacer box, which should be the first thing you see when openning the box. We pack it loose because 90% of our UPS damage was done to the petcocks sticking out the bottom. We figured if we packed them loose, they could no longer damage the valve or the radiator.
Hey Tom. I'm glad you're searching the forum this weekend...I figured I would just email you Tuesday.
First let me say that radiator is AWESOME. The quality and workmanship that went into that product is spectacular. I'm very proud to have a DeWitt radiator in my Corvette Project.
Now, I admit I opened the box without thoroughly checking all the packing so it's entirely possible it was taken with the box.
So yep, when I took out the old rad, I slipped it into that box, and set it out front of my house. Later that afternoon, yesterday, I went out and the box and radiator was gone. No big deal, since the old rad had a big hole in it, but it seems the petcock is gone too.
Thanks for the info and checking in.
