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Apr 26th, 2026 | | AD Chevy Trucks  Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
Lots of work on Brad's part ... pure enjoyment (and references) for you!
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| | | | Joined: Jul 2019 Posts: 95 'Bolter | | 'Bolter Joined: Jul 2019 Posts: 95 | ‘49 Chevy 3800. Has the fresh air heater. The heater has water inlet and outlet, water pump and thermostat housing has outlets and the heater valve has inlet and outlet. My question is how is all of this plumbed together. Truck came to me with all of this unhooked and I’ve searched high and low for the diagram but no luck. Can someone please provide a schematic for hooking all this up? Thanks much!
1949 Chev 3800
| | | | | Joined: Feb 2004 Posts: 29,799 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,799 | The coolant can flow either way through the heater core. Flow direction is out of the thermostat housing to the heater core, and the return line goes to the water pump. If there is a cable controlled valve regulating coolant flow through the heater, it's usually better to plumb the "pressure" hose from the thermostat housing to the valve.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
| | | | | Joined: May 2015 Posts: 11,067 Housekeeping (Moderator) Making a Stovebolt Bed & Paint and Body Shop Forums | | Housekeeping (Moderator) Making a Stovebolt Bed & Paint and Body Shop Forums Joined: May 2015 Posts: 11,067 | Jerry's right about the heater core flow can be in either direction. But it might be better to connect the return hose to the highest port on the heater core to be sure that any air in the core gets purged out and back to the engine. There may be enough flow to flush air in either direction, but it doesn't hurt to help it along. I think Brad Allen has the installation diagram in his photo collection. I'll see if I can track it down. [on edit] I looked thru Brad's Flikr account, but didn't find the heater install instructions. Too many photos to look thru, and get distracted. If you need something to do (insomnia?) I'd recommend browsing thru his stuff.Should be somewhere in this album.
Last edited by klhansen; 11/30/2023 9:04 PM.
Kevin 1951 Chevy 3100 work truckFollow this saga in Project JournalPhotos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together. | | | | | Joined: Jul 2019 Posts: 95 'Bolter | | 'Bolter Joined: Jul 2019 Posts: 95 | Thanks to both of you for the tips!
1949 Chev 3800
| | | | | Joined: Jul 2019 Posts: 95 'Bolter | | 'Bolter Joined: Jul 2019 Posts: 95 | Thanks much klhansen. Went through the album and found a picture of just what I needed! Big help! D
1949 Chev 3800
| | | | | Joined: May 2015 Posts: 11,067 Housekeeping (Moderator) Making a Stovebolt Bed & Paint and Body Shop Forums | | Housekeeping (Moderator) Making a Stovebolt Bed & Paint and Body Shop Forums Joined: May 2015 Posts: 11,067 | Thanks much klhansen. Went through the album and found a picture of just what I needed! Big help! D Do you remember how many pages in that was? I'd like to see it also, but didn't get that far in.
Kevin 1951 Chevy 3100 work truckFollow this saga in Project JournalPhotos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together. | | | | | Joined: Apr 2020 Posts: 322 Professional procrastinator | | Professional procrastinator Joined: Apr 2020 Posts: 322 | There is a pic near the end of the first page which shows routing.
1947.2 GMC 1/2T SWB panel
1947.2 GMC 1/2T long bed
1948 GMC 1/2T short bed
| | | | | Joined: May 2015 Posts: 11,067 Housekeeping (Moderator) Making a Stovebolt Bed & Paint and Body Shop Forums | | Housekeeping (Moderator) Making a Stovebolt Bed & Paint and Body Shop Forums Joined: May 2015 Posts: 11,067 | There is a pic near the end of the first page which shows routing. Thanks, I saw that, but I was looking for the installation instructions for the heater. I recall seeing a document posted that showed that. I'm sure it's around here somewhere. I could have sworn Brad was the one that posted it. 
Kevin 1951 Chevy 3100 work truckFollow this saga in Project JournalPhotos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together. | | | | | Joined: Sep 2009 Posts: 5,878 Gearhead, Stovebolt Tech and Parts Tracker, Mod for Swap Meet and GTT | | Gearhead, Stovebolt Tech and Parts Tracker, Mod for Swap Meet and GTT Joined: Sep 2009 Posts: 5,878 | Thanks, I saw that, but I was looking for the installation instructions for the heater. I recall seeing a document posted that showed that. I'm sure it's around here somewhere. I could have sworn Brad was the one that posted it. Kevin, Is this the thread that included pics from Brad?  Here is the 1951 instructions main diagram. The actual written instructions start 2 pages back. I took a gander and "Brad's" photo album - WOW! After an hour, I hadn't even scratched the surface. Thanks for sharing that info! 
~ Dan 1951 Chevy 3 window 3100Follow this story in the DITY Gallery"My Grandpa Carl's Truck and How it Became Mine"1966 Chevelle (Wife's Hot Rod) | 2013 Chevy Silverado (Current daily driver) US Army MSG Retired (1977-1998) | Com Fac Maint Lead Tech Retired (1998-2021)
| | | | | Joined: May 2015 Posts: 11,067 Housekeeping (Moderator) Making a Stovebolt Bed & Paint and Body Shop Forums | | Housekeeping (Moderator) Making a Stovebolt Bed & Paint and Body Shop Forums Joined: May 2015 Posts: 11,067 | Dan, That link that bowtietim posted (and you duplicating above) was what I was thinking about. Yes, Brad's collection is pretty awesome. Again, you earned that "Parts Tracker" handle. 
Kevin 1951 Chevy 3100 work truckFollow this saga in Project JournalPhotos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together. | | |
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