CranioPazzo

hello can someone help me...i have a 76 omega in which i just took out the straight 6 motor and put in a olds 307... I have two heater hoses comming from my firewall which both hooked up the water pump on the 6...now with the 8 i know one goes to the pump but where does the other one go? I have the two that go to the radiator and the one from the thermostate housing to top of pump...any help??

67 Cutlass Freak

One heater hose will go to the heater control valve on the R/R of the intake. No heater hoses go to the radiator, so you can block those off.

redoldsman

I believe the heater control valve is on the right rear of the intake manifold. The second hose should go there.

CranioPazzo

ok so the top goes to the water pump and the lower goes to the heater control valve in rear of intake near distributer?...i also have no AC in the car it was removed prior to motor swap...do i need the valve still?

CranioPazzo

i have a 76 omega....i just took out the straight 6 and put in a olds 307...one heater hose goes to the water pump and the other to the heater control valve...if i dont have AC in the car do i still need to hook up the hose to the valve?

67 Cutlass Freak

The heater control valve controls the flow of hot coolant to your heater core. It is normaly actuated by a vacuum line coming from your heater control unit in the dash. If you don't drive the car in the summer and want hot air blowing on you always, than you don't need the heater control valve. A nipple will do for you.

CranioPazzo

you mean if I don't drive it in the winter? i do drive it in the summer...should I just buy a valve and install it in my intake?

MDchanic

If you only drive in the summer, get a pipe thread plug for the hole in the intake and cap off the water pump nipple.

- Eric

CranioPazzo

ok it looks like I have something in the intake where the valve would go I could connect the hose to that with a hose clamp?...also which hose would go to the water pump...the lower or upper hose?

Oldsguy

No, run the hose from the heater core directly to the back of the engine, you can use a nipple instead of the control valve, don't remember the thread size but not too hard to figure it out by looking at the old valve.

oldcutlass

The 5/8 hose (bottom) goes to the manifold and the 3/4 hose (top) goes to the pump.

joe_padavano

Time to clarify a few things in this thread. First, the heater control valve does NOT control heat in the heater. It is only used to shut off the heater flow completely if you have the A/C in the MAX COLD position. Heater-only cars do not even use this valve. There is a temperature blend door in the HVAC box under the dash that regulates the temperature inside the car by blending (hence the name) air passing through the heater core with air taken directly from outside. Even if you have A/C, the heater valve is open at all times unless the A/C is on MAX. You can and should delete the valve if you do not have A/C, though if the car originally had A/C, be sure the vacuum control lines are plugged to avoid any vacuum leaks. Also, if the car originally had A/C, you do need to retain the vacuum controls to operate the flapper doors in the HVAC box under the dash.

As noted, the heater hoses to to the water pump and the rear passenger side of the intake, where the heater control valve currently resides. Simply cap the extra fitting on the radiator. This is a Chevy thing and is not used with Olds motors (the I6 is a Chevy motor).

joe_padavano

Please note that I've moved and merged all your other posts with this exact same question into this thread. You will really get a better answer if you don't shotgun the same question to every sub-forum on the site, as keeping all the responses in one place lets people correct potential incorrect information that might be posted.

CranioPazzo

ok thanks everyone

Octania

I would add to JP's excellent as usual input:

If you look carefully, you will see that the two heater core nipples are different sizes- subtle but not negligible. 3/4 [6/8] vs 5/8"... So, run the 3/4 heater core hose to the thing on the engine that has the 3/4 nipple, and ditto for the 5/8. Makes sense.

If you remove the vacuum controlled valve at the RH rear corner of the intake, DO NOT USE A HARDWARE STORE NIPPLE. Use a factory type heater hose fitting with the restriction of about 1/4" ID. You can buy new ones from the Voldemort Vendor or I have used ones. Verify your intake's thread size, it will be a standard pipe thread 3/8 [rare early engines], 1/2, or 3/4" NPT.

CranioPazzo

ok will do so ill run the 3/4 to the rear of the intake where the heater control valve would normally go and the 5/8 to the water pump..and since this car did come with factory ac I'll keep all the vacuum lines installed...so I'll have to cut the one hose since it originally went to the front of the L6...would this be a good summary?

joe_padavano

Yes. Just be sure that you plug that hose that went to the heater control valve on the I6.

joe_padavano

455man

Just curious but what's the purpose of this? To prevent too much water flow?

CranioPazzo

hey guys got a question hooked everything up but the starter won't engage...no clicks or anything...got the battery and alternator wire connected and ignition connected...even checked my gears and tried to start in neutral with no luck....any other ideas?

oldcutlass

Is the purple wire going to the S terminal on the starter. Make sure there is 12v there when the key is placed in the start position, if not your problem may be at the neutral safety switch.

CranioPazzo

it's a black wire and it's hooked up to the right side stud and the 12v is hooked up to the main one with the alternator one...should I disconnect everything put the key on then re-connect?

MDchanic

Take a look at this thread from a few days ago.

If that doesn't do it, ask away.

- Eric