I recently bought a '67 Big Block Camaro from the south flordia area. The guy that owns it had the heater core(inlet & outlet) capped, no heater hoses installed and the water passages at the intake and water pump plugged. I have ordered a new heater core (just in case the one installed leaks)hoses and new fittings.
My question is which heater hose goes where? Does the top hose from the heater core connect to the water pump or intake?

Thanks in Advance, Great Site!

If it's like a SB one fitting is 3/4 and the other is 5/8. The 3/4 goes to the water pump and the 5/8 goes to manifold on a SB.

To add what Winch said, you have to go through the vacuum actuated heater control valve mounted on the right fender before you go to the heater core. If it's the same as a small block.

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Drew

69' X-11 350, Turbo 350, Factory Air, PS, PB, 12 Bolt (410 gear) & NOT AN SS

A what? Mine has hoses straight from firewall to pump & manifold. Am I missing something?

Please explain this heater control valve Drew. I have never seen one.

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...Dennis
"The '69 (http://chevelles.com/showroom/ww.jpg), the '96 (http://www.camaroslimited.com/graphics/memcars/96ss.jpg) & the club (http://camaroslimited.com/)"

Please explain this heater control valve Drew. I have never seen one.

DJD,
I believe you will find those on the shelf next to the Lumber Stretchers.

The heater hose "shut-off valve" was used on AC cars....It shut off the flow of hot coolant while using the AC....69 was the first year for this ??? ...

There is no shut-off valve on 67-8, but it can be retro-fitted by tying into the vacuum supply line to the cowl flapper valve.

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The Red Beast http://www.geocities.com/casanoc

"If it's like a SB one fitting is 3/4 and the other is 5/8. The 3/4 goes to the water pump and the 5/8 goes to manifold on a SB."

So which hose goes where on the heater core tubes??? Thx, I will save this b/c I will forget just sure as can be expected! pdq67

Well one tube is bigger than the other and one hose is bigger than the other. Let's see, which should go on which. It seems intuitive but when I pulled the 6 cyl out of my 68 the big hose was on the small tube and visa versa. I guess as long as they don't leak it will work either way.
That's interesting about the 69 control valve. What is the vacuum controlled flapper? Is that on a cowl hood? If so was there a valve on non-cowl hooded 69s with a/c?

I've often wondered why the tubes are different sizes; does anybody know ?

I would guess to slow the flow of coolant sufficiently so that on hi blower there is enough heat transfer to the core so it is able to warm the air. Just a guess http://www.camaros.net/forum/smile.gif

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67 prostreet BB Camaro
71 BB SS Chevelle (clone)
2002 35th anniv SS Z28 conv.

Or maybe it was the design engineer for the inlet tube was not talking to the design engineer of the outlet tube http://www.camaros.net/forum/smile.gif

Now thats more likely http://www.camaros.net/forum/smile.gif

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67 prostreet BB Camaro
71 BB SS Chevelle (clone)
2002 35th anniv SS Z28 conv.

<BLOCKQUOTE>quote:</font><HR>Originally posted by Rons68:
I've often wondered why the tubes are different sizes; does anybody know ? <HR></BLOCKQUOTE>

1- so we have to get 2 sizes of hose
2- so we can all ask "why?"

It's sorta like the Rolling Rock "33"

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68 Coupe, 350 4-speed
Jim's Camaro Corner (http://www.personal.psu.edu/jxu109/)

OK, I will bite.

What's "Rolling Rock 33" outsida just beer?

Something only a Keystone state guy/gal would know about!!! pdq67

33?bottles of beer on the wall/????
heater really wont care which hose oges to which side as long as hot water flows thru it...
i had a chevy van that the heater wasn't working very well, i reversed the hoses,it back flushed itself,for a week,and i draind the radiator,unhooked the Lower hose,and Lotsa junk came out, Oh the heater worked better,and i never did put the hoses back "correctly" LOL
big hose to big Nipple http://www.camaros.net/forum/smile.gif

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'67 RS 427,4 Speed
Disc brakes,console, fold down rear seat,heater,
Radio Delete, Cowl hood,front,rear spoilers,
Black/black; white bumblebee stripe
Click to see my Camaro (http://us.f1.yahoofs.com/users/8a118c5b/bc/camaro+pics/67rscamaro427email.jpg?bcw8KV9A97U9f2_Q)

On the back of every bottle of Rolling Rock, there is a pledge. At the bottom of the pledge is the mysterious number in quotes "33". Nobody knows why it's there, but there are a lot of theories.

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68 Coupe, 350 4-speed
Jim's Camaro Corner (http://www.personal.psu.edu/jxu109/)

SORRY GUYS, I hadn't checked back on this subject! Maybe a "senior moment"?
18436572 appears to be correct, the heater control valve came in 1969 on A/C equiped cars.
The valve mounts on the inner right front fender and looks like Napa/Balkamp # 660-1061 if you have an illustrated book you can see what it looks like (GM 69'-80'). I thought Rick's had them but I don't see it in the on-line catalog. Could be I saw them in National Parts Depot catalog and they don't have an on-line catalog, yet.

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Drew

69' X-11 350, Turbo 350, Factory Air, PS, PB, 12 Bolt (410 gear) & NOT AN SS

Thanks for all the responses.

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Gary
1967 Camaro SS/RS 396-375

Ricks, does carry this "heater shut off valve", page 45 in the new catalog. It was in the A/C section.

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Drew

69' X-11 350, Turbo 350, Factory Air, PS, PB, 12 Bolt (410 gear) & NOT AN SS

Heater design tidbits:

The hose from the outlet fitting (manifold) always goes to the bottom heater core fitting, and the hose from the inlet fitting (water pump) always goes to the top core fitting; that way the core is always full of coolant and there's no "gurgling" sounds from air bubbles audible from inside the car.

The upper hose from the core back to the water pump is slightly larger in diameter so it always has lower pressure (carrying the same volume of coolant) to maintain steady coolant flow at low rpm so constant temperature control adjustments by the customer aren't required.

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JohnZ
CRG
'69 Z28 Fathom Green

I hooked everything up today and it worked fine.

Thanks for the help,

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Gary
1967 Camaro SS/RS 396-375 4sp.

http://community.webshots.com/user/amike95

I do not understand how an ac car would not have this heater hose 'shut-off valve' regardless of the year. Hot water flowing into your heater core while running the ac would be counter productive. The air conditioning would not work correctly. Surely GM didn't try this?

The two are separated by a sealing door, many cars use the full time heater core flow method.

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Don~ ZZ430DropTop (http://hometown.aol.com/zz430droptop67rs)
~~~~and~~~~
70 RS (http://hometown.aol.com/performancespecs)
67 RS/SS Convertible, 70 RS

The sealing door being located in the under the dash ac/heater box?

So what are some of the theorys?

I'M a PA transplant, but I always heard it
(33) reflected the year of prohibition.

Rick

I didn't know there was so much thought put into heater cores. Wow.

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Matt Jones
1969 Base Camaro
Vortec 355, Perf. RPM, Demon Carb., TH-400
All sheetmetal is NOS GM
See my webpage at: http://www.geocities.com/compuboy007/

That's how the A/C discharge air temperature is modulated - that's why they're called "re-heat" systems. The incoming air from the blower goes through the A/C evaporator core and gets cooled to the maximum, then it goes through a blend chamber where a diverter door (operated by the temperature control) allows a certain amount of the cooled air to either bypass the heater core (for the coldest possible air at the outlets) or allows an adjustable portion of the cool air to pass through the heater core to warm it back up to whatever outlet air temperature the occupant prefers. When the control is set in "max" (recirculating inside air), vacuum is applied to the heater hose water valve, stopping hot coolant flow through the heater core; in "norm", the water valve is open and there is full flow of hot coolant through the heater core to allow for "re-heat" discharge air temperature control.

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JohnZ
CRG
'69 Z28 Fathom Green