Ok stupid question...I searched a few times and couldn't find what I needed. I'm not going to run my heater for a while. And I'm not sure if I need to run some type of loop from the water pump to the intake. I wouldn't think that was necessary but I've seen guys doing this in the past and never really knew why.
It is not necessary. Just plug the connections. A loop of hose would look so ugly. I have done it to get home with a leaking heater core but that was an emergency situation.
It depends on the engine. Some engines need the heater circuit to cool properly. On others the cooling is not effected by blocking the heater circuit. General rule, newer engines are more likely to need the heater circuit than older designs. Another indicator; if the heater system originally connected to the engine had a heater control valve, that normally means when the heat is off no water flows, so that is the same as plugging the fittings.
CutawayAl is right. I always plugged the outlets off on SBC engines, but when I set up my 350 for the raodster and blocked them off I was running around 225 degrees on the road and over 240 in town. A friend of mine told me that on the later 350s you need to run a by-p*** hose. Mine is out of a 87 to 92 Chevy truck with the roller cam. I installed the by-p*** and the temp never gets above 200 now, and is around 190 on the road. It was news to me, and I would have spent alot of time trying to figure that one out. I can't explain what's different but it is. It has something to do with the water not getting to the intake and circulating through the heads.... All I know is it worked for me.
Or put a valve in-line and close it. The water won't circulate if you just close on side. Whatever you do keep it simple, cars should be simple.
I have a late 350 Chev crate motor in an ot car. The heater ports on the water pump are plugged. No cooling problems, so I'm not sure what the answer is.
Cool its a sbc probably a late 70's model and the water pump is the "heavy duty" style I think...I'm also pretty sure it has a threaded port so I can just put a plug in it. Thanks again guys!
unscrew the ****** and screw a br*** plug into inlet and outlet. hose loops, clamps and rubber plugs just look bad.
Like oldschool said, late model 350's with the vortec heads need a heater byp***. They come with one from the factory. The later vortec heads don't have the byp*** p***age in the heads that an older sbc had, the one that works with the additional hole in the block under the p*** side of the water pump. Just run a hose from the intake to the water pump like most non sbc motors and your cooling system will run cooler and more consistent. You can drill the thermostat, but I've found running the byp*** hose works much better.
Ditto to the thermost by p***.....GM liked to use the heater core for that function, and the control valves were designed to by p*** the heater, when the temp control was set to the "off" position. 4TTRUK
I plugged off the outlets in my BBC 454 last spring. Now it runs hotter that ever, 240 degrees or more on hot day. Is it a coincidence? Maybe I'd better change out the heater core ASAP and maybe that will cool it down some???
Although this is a forum about traditional stuff, you started out not saying what kind of engine you have. It can go beyond the byp*** circuit. I have seen engines with cold side t-stats which rely water flowing through the heater circuit to expose the t-stat to the engine's water temp. Some engines use the heater circuit to even out coolant flow in the engine. With the heater plugged those engines will tend to overheat.
Yes I realized the error in my ways! I also have heard of different engine families that do have those cold side stats, and the heater circuit that balances out the flow...That was my only reason for concern...I'm sure by the end of the summer I will be putting the heater back in but I'm not gonna need it for a while and I have bigger fish to fry! Thanks guys. This is what this forum is all about in my mind. I love to see the guys who come out of the woodwork to help a rookie like me!
If you look closely you can see the plug in the top of the water pump and the front p***. side of the intake! I'll let you know how it goes, hopefully I'll know soon! Don't worry the valve covers are just for painting and mockup purposes!
If you are going to remove the heater to work on it or if it leaks get one of those T's from the parts house that gets put in the heater hose as part of a cooling system flush kit. They are designed to go either 5/8 or 3/4 so you don't have a connection problem. That's an easy five minute fix and you won't have to worry if you disturbed coolant circulation that is needed to keep the engine temp under control. If it ends up as high as the tank on the radiator it works good to burp the cooling system when you fill it too.
A 80's/early 90s Honda has a neat, small heater control valve. It can be operated with a cable or by hand. It is one of the best I have ever experienced at stopping the coolant flow. Salvage yards are full of them. So they are CHEAP. I got two for 5 dollars.
Yep got one on the shelf in the garage! I think those things are priceless! Not the heater controll valve but the flushing T!
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