Heater Core hose hook-up

[jvandyke]

Originally Posted by Anonymous D OMC Blitz (October 2006) issue Tech Tip, here: Cooling System (Vacuum hoses connections, are part of the Tune Up Tech Tip, Part I, and are located in the Engine Maintenance section of the website).

good read, thanks, my question is simple and a bit embarrassing, I'm looking in the engine bay for the two over/under fittings that are the supply and return for the heater core. I see one hose going from thermostat housing along valve cover, behind carb, left turn (toward passenger side) and into firewall.
There's another that comes out down low, under the carb, near wheel well and goes to the water pump housing. My system has been hacked up, and I'm new to this whole thing thus my ignorance. I suspect the other is supposed to be by this second one but has been covered or something.
Here's a little video showing what I've got now. Drive-In Two iMovie
BTW
Here's a little saying I came up with once (at least I think I came up with it)
"being ignorant is no cause for embarrassment, but remaining ignorant is"

[Anonymous D]

There's a diagram of the heater hoses
connections on page 5. It's laid out
as you see them in the car; the lower
hose in the diagram represents the
lower hose outlet on the car.

[jvandyke]

Okay, here's the deal. From heater core, top line doesn't turn towards front of car but heads straight out of box (toward driver) through firewall bends along rocker cover hooks up with thermostat housing.
Lower line has been replumbed, to go straight down, then out "normal" position (I think) it then heads to water pump.
So, heater valve not in play at all, system always "open" always "Hot" (not sure if anything works, PO says no, must be why he has a spare heater core and what is wrong? plugged up? fan blows.)
Why this rerouting I wonder? Weird.
Here's pictures of the whole "mess". Would be so easy to rehook heater valve. I bet the control broke behind the dash and this was the "fix".
heater

[Anonymous D]

Replace the "homemade" tube with
a genuine Opel GT heater outlet tube,
then configure the hoses in the same
configuration as stock.

Also, your photo shows an incorrect
carburetor. The "Holley-Weber" is
from a Ford Pinto, and its throttle
connection is towards the front of the
car. The correct Weber 32/32 DGEV carburetor
has a throttle connection towards the rear of the
car.

[jvandyke]

Originally Posted by Anonymous D Replace the "homemade" tube with a genuine Opel GT heater outlet tube, then configure the hoses in the same configuration as stock. Also, your photo shows an incorrect carburetor. The "Holley-Weber" is from a Ford Pinto, and its throttle connection is towards the front of the car. The correct Weber 32/32 DGEV carburetor has a throttle connection towards the rear of the car.

I think, from looking at the FSM that the tubes are over/under and I have one there now, the other was rerouted. Still a bit foggy on where the heater valve is supposed to be. I guess it doesn't ultimately matter, so long as it works, I'll probably put the valve where it's convenient but out of the way of possible future changes (cold air intake).
The PO has since told me he bypassed the valve and therefore the heater core was always producing heat, the blower motor works but is noisey (sounds like leaves in there to me) but the lower control slider doesn't work anymore on either the cable that is supposed to be hooked to the bypassed heater valve, or on the heater box where it is supposed to open and close a valve to route air. It doesn't. I have to rip in here an put things to right.

as for the carb, it's a Holley 5200 (I think), an 'inverted" Weber (mirror image) and it has been installed backward to put the primary away from the block, therefore throttle cable on front. Seems to work okay but I've only had the car 2 weeks and it's the dead of winter here so not driving it. I may redo it all depending on how well it runs for me.

[jvandyke]

I'm thinking of putting a heater valve on the lower of the two core hoses; the "return" hose according to FSM, but I think we decided it didn't really matter.
I'm pretty much married to this because some PO somewhere moved my coolant lines around to accomate something. FI, turbo, who knows.
The heater control cable comes out by this hose and nowhere near the other.
Just checking to see if anyone thinks this would be an issue.


I also have a question on the valve itself but I think it fits better here:
http://www.opelgt.com/forums/part-su...r-valve-2.html

[tekenaar]

The heater core flow is: Water Pump nipple is SUCTION ("OUTPUT" FROM heater core); T-stat housing nipple is PRESSURE ("INPUT" TO heater core) . . .

[jvandyke]

maybe this should be better placed over here?

http://www.opelgt.com/forums/part-su...tml#post118365

[tekenaar]

Originally Posted by jvandyke The FSM, (http://www.opelgt.com/forums/group-9...e-hook-up.html post 15, 16) calls the lower hose a "feed" (the one to the water pump) and the top the "return", FWIW.

. . . and THAT's absolutely correct, you just interpreted the engine side connections of the A and B hoses backwards, i.e. the heater core bottom "A" hose is connected to the T-stat (pressure, heater core feed) while the upper "B" hose is connected to the WP (suction/heater core return).

Part of the confusion is perhaps due to terminology . . . the radiator lower hose is the suction/feed side for the WP!!, and suction/return by WP nipple for the heater core. The pump pressurizes the block/head and thus the T-stat housing and upper radiator hose, which becomes "feed" for both radiator and heater core. Clear?! . . .

[jvandyke]

Here's how mine ended up.

[N61WP]

I want to unhook the hosesfrom the heater core and remove the hoses and valve to add room for my side drafts. Can I just plug off the two water outlets from the engine, or do I need to loop them together for circulation?
ThanX,
Jc

[jvandyke]

as you can see from above, my car was hacked by PO for dual side drafts, don't know how it worked out, car came to me with a single downdraft but I inherited the re-routed heater core hoses and carved up heater box.
Anyway, I remember reading somewhere that the coolant that goes through the heater core bypass (if the valve is open) is marginal and doesn't effect the motor's heat dissipation, wouldn't be much different if the valve were shut then if the outlets stopped up or connected to each other. Someone had put themselves out a bunch rerouting my lines, looked like a lot of work had gone into it.

[N61WP]

DUHHH! I'm having more and more of these senior moments lately! Of course, if the heater valve is closed, water can't circulate, so if I plug off, nothing changes.
ThanX,
Jc