Scoop
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Thought I'd run this by folks to see if I'm thinking correctly.
I'm installing a new Ice Crusher in-dash heater.
Instructions say to prime the new heater core with a garden hose BEFORE attaching in/out hoses to the heater core. I can't do that in this Michigan winter.
Note that these instructions are for installing the heater WITHOUT the optional electric water pump (see below) and, without the electric water pump, the heater core would otherwise have you obtain the fresh coolant supply for the heater core by putting a Y connector in the *upper* radiator hose -- something that is NOT done when using the optional electric water pump. But ... read on.
Wondering if this approach might work instead of the garden hose to prime the heater core:
First, how it's installed/routed:
Heater core INPUT: The coolant input to the heater core comes from a Y connector that's installed in the oil cooler bypass hose. At this Y connector, some (not all) coolant is routed to an electric water pump. This is what feeds the coolant (input) to the heater core. By being installed @ the oil cooler bypass, this electric pump will constantly circulate coolant even when the bike is just started/is below temp and will better move coolant thru the heater core when at idle.
Heater core OUTPUT: The heater core coolant output goes to a Y connector in the lower radiator hose which, of course, adds coolant (back) to the line that feeds the engine. The oil cooler bypass, of course, gets coolant from this main coolant supply BEFORE it gets to the engine (so it's never starved for coolant when the engine thermostat is closed) and also constantly feeds coolant to the electric water pump.
Here's my question:
To prime the heater core without doing it with a water hose before I connect the upper and lower hoses @ the heater core, can't I simply remove the radiator cap, keep the radiator full of 50/50 and turn the electric water pump on without starting the bike?
The pump should (always) draw coolant from the lower radiator side. It will directly feed coolant thru the new hose, thru the top of the heater core and out the lower radiator Y connector (priming the core), and adding it back to its own supply. Adding coolant directly to the radiator while doing this should provide the needed coolant to fill the system to accommodate the heater and new hose while (hopefully) allowing at least some of the air to escape the loop thru the open radiator (thru the upper radiator hose via the Y @ the oil cooler bypass).
Does this sound like it would work or am I totally off base?
I'm no cooling system expert, but the way I see it, the electric pump would be providing the pressure to prime the heater core no differently than a garden hose would, provided the air in the system has place to escape.
I might have to crack open the upper heater hose to allow air out if it can't otherwise make it out by going through the other side of the Y connector @ the oil cooler bypass and thru the upper radiator hose/radiator.
Would appreciate any input. Thanks.
I'm installing a new Ice Crusher in-dash heater.
Instructions say to prime the new heater core with a garden hose BEFORE attaching in/out hoses to the heater core. I can't do that in this Michigan winter.
Note that these instructions are for installing the heater WITHOUT the optional electric water pump (see below) and, without the electric water pump, the heater core would otherwise have you obtain the fresh coolant supply for the heater core by putting a Y connector in the *upper* radiator hose -- something that is NOT done when using the optional electric water pump. But ... read on.
Wondering if this approach might work instead of the garden hose to prime the heater core:
First, how it's installed/routed:
Heater core INPUT: The coolant input to the heater core comes from a Y connector that's installed in the oil cooler bypass hose. At this Y connector, some (not all) coolant is routed to an electric water pump. This is what feeds the coolant (input) to the heater core. By being installed @ the oil cooler bypass, this electric pump will constantly circulate coolant even when the bike is just started/is below temp and will better move coolant thru the heater core when at idle.
Heater core OUTPUT: The heater core coolant output goes to a Y connector in the lower radiator hose which, of course, adds coolant (back) to the line that feeds the engine. The oil cooler bypass, of course, gets coolant from this main coolant supply BEFORE it gets to the engine (so it's never starved for coolant when the engine thermostat is closed) and also constantly feeds coolant to the electric water pump.
Here's my question:
To prime the heater core without doing it with a water hose before I connect the upper and lower hoses @ the heater core, can't I simply remove the radiator cap, keep the radiator full of 50/50 and turn the electric water pump on without starting the bike?
The pump should (always) draw coolant from the lower radiator side. It will directly feed coolant thru the new hose, thru the top of the heater core and out the lower radiator Y connector (priming the core), and adding it back to its own supply. Adding coolant directly to the radiator while doing this should provide the needed coolant to fill the system to accommodate the heater and new hose while (hopefully) allowing at least some of the air to escape the loop thru the open radiator (thru the upper radiator hose via the Y @ the oil cooler bypass).
Does this sound like it would work or am I totally off base?
I'm no cooling system expert, but the way I see it, the electric pump would be providing the pressure to prime the heater core no differently than a garden hose would, provided the air in the system has place to escape.
I might have to crack open the upper heater hose to allow air out if it can't otherwise make it out by going through the other side of the Y connector @ the oil cooler bypass and thru the upper radiator hose/radiator.
Would appreciate any input. Thanks.
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