Okay I have heard about 50/50 on can you or cant you block off the heater hoses at the water pump I removed the water pump and removed the press in fittings and tapped the holes with a 3/8 and a 1/2 NPT tap and put hex plugs in there for a cleaner look as I am not going to be using a heater, or should you leave the press in fittings in there and loop the 2 outlets together???

 

I've heard both too. I'm running a vintage air with a electric solenoid operated heater control valve. I have not found an electric (non-vacuum) operated valve with built in bypass. Mine has not had any obvious overheat, etc.. problems as it's plumbed.
That being said, Crusader Marine uses the 6.0 block in a marine engine. No need for the heater hoses, but they loop the water pump inlet/outlet together. I think I'm going to add a small tube bypass in front of my heater control valve to allow some circulation.

 

I just started a thread regarding a bypass heater valve. Keeping the coolant flowing seems an important feature in my estimation. Perhaps it works without maintaining the flow, however I feel that it helps to control the thermostat operation by providing the appropriate increasing water temperature. Why would GM have designed it that way if it weren't necessary, is how I look at it. I'm yet to hook up my heater, so in the mean time I'm using the U hose to maintain circulation. Maybe someone has done a side-by-side test both ways?

Andy1

 

It won't hurt a thing to block them off. All g-body(probably most all) cars have a vacuum operated heater valve inline in the hose. When the heater is off the water stops flowing, and they don't overheat because of it.

 

I just used a molded gates hose that fit and had a pre-bent 180 curve. I don't have heat on the car and the car runs normal temperatures. I bought it thru an Oreillys and gm also can get the hose. I believe it is factory off of an astro van.

 

I bought this.. http://cgi.ebay.com/ebaymotors/ws/eB...view=all&tid=0

Seems like a good idea. I haven't ran my engine yet, but I think it'll do what you need. way eaisier than removing the water pump and all that ****.

 

AutoZone #4354 - 3/4 on one end, 5/8 on the other.

Couldn't open the ebay link - is this the same thing?

 

^^ yep same thing. Dang i wish I knew autozone had them..

 

bb you're the man. i used bulk hose, and (needless to say) it has a kink in it, which obviously impedes coolant flow. i was thinking someone needs to make that...

 

If you notice the Meziere electric pumps provide plugs and ports for the heater hoses. There is not any benefit to running a jumper hose between the two heater ports.
I will be running my Meziere plugged as shown on this picture from their website:

 

Some thermostats have holes around the perimeter of them to allow coolant to circulate when the thermostat is closed. My stock thermostat had no holes. Whether it's the bypass hose or holes in the thermostat, the reason for them is to get hot water to the thermostat element to let it "feel" the heating water. If the sensing element does not get exposed to the real temperature of the engine as it's warming up, it will take longer to warm up and possibly overheat in the process since the thermostat is closed at the sensing element where the water is much colder.

Look at your thermostat, does it have holes to allow coolant to circulate when it's closed? If it does, you don't need the bypass hose.

The factory probably did it to allow hot water to the heater sooner (before full warm up and thermostat opening) and get warmed water to the thermostat's sensing element.

 

Thanks bb.

 

I got the p/n from someone else - on Steve's Nova Site I believe - just passing on the info so others can benefit just like I did.

 

Mine are blocked off and I will just kkep an eye on the temp gauge, If I have any adverse effects I willpost them. Thanks Again for the opinions and replys