[sig sauer]

ok i was given a coolant heater and i know that it istalls with the 5/16 heater hose but on my water pump which is the in and which is the out so that i make sure to line it up right, i am talking about the heater core hoses, which one is pumping into the heater core and which is the return from the heater core? ohh yea 400 bb if anyone needs to know

 

[K.C.]

I'm not positive about the 400, but the typical situation, (including my 31 is that the the hose coming out of the intake manifold is the feed to the heater core. This line will also have the shut off valve(if you have A/C). The return line from the heater core goes back in to the water pump and is circulated back through the block to be reheated.

 

[sig sauer]

yes well i don't have any hoses comming off of my intake manifold, just the two comming off of the water pump itself. and then the mains to the radiator and some vacum lines nothing on the intake.

 

[K.C.]

Is there something on the heater to indicate the direction of flow? Most of the inline heaters that I have seen use convection to circulate the coolant, so I don't think it would make a difference as to which heater hose you splice into. My understanding is that the heater will warm up the block and the heater core either way.Just have to make sure the valve is open if you have one. If the heater has a pump impeller, then I could see the direction of installation making a difference. I had a look in another manual that covers the 400, but there wasn't a coolant flow diagram that shows which is the in/out on the heater core.

 

[Chump]

Does this help some? Remember to keep your temp selector on the dash pushed over to heat for better circulation.

 

[sig sauer]

Thanks chump you are awsome.

 

[DennisH]

Was just browsing through the posts and i noticed that trucks with air conditioning should have that little shut off on the heater hose does that include an 89 318 w/ ac cause mine dosnt have one oh and there just happens to be a golf tee in a vaccume line thats dangling in the area..... I wonder why any one would remove it. cant be good for ac performance can it ?

 

[Chump]

Was just browsing through the posts and i noticed that trucks with air conditioning should have that little shut off on the heater hose does that include an 89 318 w/ ac cause mine dosnt have one oh and there just happens to be a golf tee in a vaccume line thats dangling in the area..... I wonder why any one would remove it. cant be good for ac performance can it ?

I guess it's just easier to remove it than spend $10 at Autozone for a new one. There should be one inline on your truck.