Original coolant expansion tank install - The 1947 - Present Chevrolet & GMC Truck Message Board Network

**71CHEVYSHORTBED402** · 03-20-2017, 02:42 PM

Apparently these were dealer installed. Some factory, which MAY be limited to govt. trucks. I'm guessing they were dealer installed varying on State requirements.

Anyway, I wanted to sample fit one onto my core support. This is my "bad" tank. Pretty sure I have a recipe for that stain. Anyway, below are the instructions. The way I read it the top mounting hole is 8.5/8" higher than the horn hole. Well, I dropped it near 1/2", because I wanted it below the ridge on the core support. Contributed to that, the instructions call for a 3/8" tilt. I don't know, I prefer things upright, though 3/8" isn't that noticeable. The tilt provides added clearance and it's more or less consistent with the slope in the top of the core support. That and you can bend the bracket.

There's not much clearance between the port in the tank and the low horn. Maybe 1.25"........It would work fine as is, though the hose may rest on the horn. I don't want any pressure on that port, and there's a lot of real estate on the LH side, especially without a voltage regulator. So I'm making a 4x4ish" plate as an option, probably aluminum. That will add up to 2" more clearance to the left, and really, more clearance in every direction. Very little of the plate will be visible, if at all.

Not exactly rocket science, but glad to have finally figured it out so I can pull the radiator. Zepplin was real helpful.................BTW, free 4-core radiator un-shipped. It's not truck correct, but it works less the port for a heater hose on a BBC........Doesn't fit the shroud.

Reggler · 03-20-2017, 03:45 PM

My '72 suburban has one of these. But it was also built with the heavy duty cooling. I feel like that is properly placed because I know it's in a weird spot to try to fill with a 1 gal antifreeze jug.

saskred · 03-20-2017, 04:33 PM

Anyone know where the overflow tank is supposed to be installed when an auxiliary battery is already installed?

**71CHEVYSHORTBED402** · 03-20-2017, 06:43 PM

Quote:

Originally Posted by saskred

Anyone know where the overflow tank is supposed to be installed when an auxiliary battery is already installed?

Nope. But I know at least one dealer sells one that sits on the RH inner fender with a "factory appearance"........I think Wes has these, Classic Heartbeat.

03-20-2017, 02:42 PM	#1
71CHEVYSHORTBED402 Senior Member Join Date: Feb 2009 Location: Northern Nevada Posts: 7,114	Original coolant expansion tank install Apparently these were dealer installed. Some factory, which MAY be limited to govt. trucks. I'm guessing they were dealer installed varying on State requirements. Anyway, I wanted to sample fit one onto my core support. This is my "bad" tank. Pretty sure I have a recipe for that stain. Anyway, below are the instructions. The way I read it the top mounting hole is 8.5/8" higher than the horn hole. Well, I dropped it near 1/2", because I wanted it below the ridge on the core support. Contributed to that, the instructions call for a 3/8" tilt. I don't know, I prefer things upright, though 3/8" isn't that noticeable. The tilt provides added clearance and it's more or less consistent with the slope in the top of the core support. That and you can bend the bracket. There's not much clearance between the port in the tank and the low horn. Maybe 1.25"........It would work fine as is, though the hose may rest on the horn. I don't want any pressure on that port, and there's a lot of real estate on the LH side, especially without a voltage regulator. So I'm making a 4x4ish" plate as an option, probably aluminum. That will add up to 2" more clearance to the left, and really, more clearance in every direction. Very little of the plate will be visible, if at all. Not exactly rocket science, but glad to have finally figured it out so I can pull the radiator. Zepplin was real helpful.................BTW, free 4-core radiator un-shipped. It's not truck correct, but it works less the port for a heater hose on a BBC........Doesn't fit the shroud. __________________ Tony 71 Custom Deluxe, SWB, 2WD, 402, A/C. I developed an assm. guide "kit" for restoring it from ground up. With assys, the guide accts for 1000s of OEM identifications and part numbers, all written in short order. 700+ images include assm, illust., charts, and points of interest. Much of the info. applies to all 67-72 GM trucks, and to a lessor degree all 67-72 GM vehicles. My build thread, and more on the guide https://67-72chevytrucks.com/vboard/...d.php?t=730025

03-20-2017, 03:45 PM	#2
Reggler Registered User Join Date: Aug 2016 Location: Brunswick, Ohio Posts: 49	Re: Original coolant expansion tank install My '72 suburban has one of these. But it was also built with the heavy duty cooling. I feel like that is properly placed because I know it's in a weird spot to try to fill with a 1 gal antifreeze jug.

03-20-2017, 04:33 PM	#3
saskred Registered User Join Date: Jun 2015 Location: Huntington Beach, CA Posts: 104	Re: Original coolant expansion tank install Anyone know where the overflow tank is supposed to be installed when an auxiliary battery is already installed?

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.