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I'll bet in Long Beach you can survive quite well without a working heater. Just do as Howard says and hook the end of the long heater hose from the front of the engine to the fitting on the top of the cylinder block and you can worry about the heater core at your leisure. When you do that little bypass operation, I recommend that you wedge something snugly up in the hose before you connect it--a piece of stick, a large marble. That will keep the coolant from taking the path of least resistance and bypassing the radiator.

OK so before I attach the long hose into the block I put a marble or something in it? Won't coolant just go into the block if I don't? Is that not suppose to happen?

Ross brought up a point not many including myself think about. The port on the head is the outlet and is fed by the water pump pressure. It will want to move water out at quite a high flow rate. If it goes in the long hose it will be directed right back into the front of the engine and will never get a chance to be cooled by going thru the radiator. Eventually that loss of cooling capacity could result in an overheating situation.

By blocking the hose with the marble or stick or anything that will prevent water flow it stops the coolant from bypassing the radiator. It will be forced to travel the normal route thru the engine and then to the radiator and back. In normal operation an amount of control is provided by the thermostatic valve and restrictions in the heater core but with neither of those in the bypass, the flow directly thru the hose will be quite strong.

If you didn't want to do the marble you could also get a fairly inexpensive shutoff valve at the parts store. Remove the hose coming from the head port at the end where it connects to the thermostatic valve instead. Place the shutoff valve in the middle to join the two hoses and close the valve. The hose is 5/8 so if you get a valve, that is the size needed.

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Or just remove the heater hose nipples from the cylinder head and water pump and install pipe plugs. JWL

Definitely a possibility but I learned the hard way sometimes those old fittings have found a home and have no intention of giving it up. I sheared a rusted one off flush with the head on one engine so am reluctant to suggest removal unless there is the capability of extracting or repairing anything that might go awry.

Ok so after carefully studying all of your remarks and showing the diagram to five different mechanics throughout today is it possible just to disconnect the long hose from the heater and put it into the cylinder head between plug number five and six? That would definitely bypass the heater. Now the shut-off valve is so there's no water coming from the radiator through the long hose correct? Is it absolutely necessary to have a shut off valve? Where I'm stuck is if I put the long hose into the head between plug five and six should coolant be going through that long hose back into the cylinder head for any reason?

Without something to keep water from flowing thru the hose, the pressure from the water pump will push water out of the pipe in the head, thru the hose and right back into the suction side of the water pump. The water just makes a loop and each time it does it gets a bit hotter. The extra heat may be enough to eventually cause the engine to run hot since a lot of water will not be going thru the radiator -- just being heated over and over as it makes the loop.

Ross suggested placing a marble or a piece of wood in the hose before you connect it to the pipe on the head. A short 1/2 inch long piece of 9/16 or 5/8 round metal rod will work too. You do want a marble or stick or metal rod large enough to stop or at least slow way down any water going thru the hose. It also needs to be large enough that it will not slip inside one of the pipes at either end of the hose and get inside the engine.

Something like the marble or stick or metal may be large enough that once it is in the hose it won't come back out so you will need to replace the hose if you ever do repair the heater. I suggested the valve for convenience if you didn't have anything else or didn't want to figure on replacing the hose down the road but you do not actually need it. By the time you repair the heater it may be time to replace the hose anyway.

Ok so I'll have the valve from Napa in the morning. I disconnect the short hose that goes to the head near plug 5 and 6 from the firewall and connect it to the longer hose with the valve in the middle. Then close the valve so no water is circulating correct? I think this is what you are saying. No marble, no stick, the valve works for me. I think I understand. Tell me I'm right. I so appreciate your help on this. In about 8 months when I need a heater I'll get it fixed properly.

You have the idea down perfectly.

So I cut the two hoses and inserted the shutoff valve between them, closed it and no coolant leaks! Thank you! It took 20 minutes. I'll post photos I a few days. I am so happy that I fixed it myself.