Hi everyone. I've got a 1999 Prerunner; 3.4L V6 engine.
I took off the 3 heater hoses at the back of the engine 3 days ago, and like a fool, did not label them.
What I remember of their configuration relative to the heater valve and the two vertical connector tubes at the rear of the engine is not what is in the standard Toyota diagram for this truck.
Plus, I slightly crimped the longer of the two thin brass firewall connectors muscling off the hose (before I thought to slice it open with a razor).
My intended fix is to jam the hose on all the way to the firewall past the "stop" ridge and hope it doesn't leak.
So I'm almost back to complete, after buying three aftermarket hoses at my local NAPA store. They are VERY close to original, but not quite the same.
So here are my questions:
1) Of the two connections at the engine block, which is outlet (hotter) and which is return (cooler)?
2) Does the direction of flow through the valve and/or the heater core matter? There's an arrow on the back or underside of the valve, so maybe it does? On a 1938 Packard, it does not matter (for the heater core).
3) In no diagram that I could find, either in the shop manual or online, is it totally clear which of the two longer hoses goes to which of the two connectors on the back of the engine. It's sort of implied by the diagram, but not totally clear. But if you can answer #1, above, that will answer #2 and #3.
Lots of stuff online, but nothing exactly helpful.
Thanks in advance for any suggestions or references.
I took off the 3 heater hoses at the back of the engine 3 days ago, and like a fool, did not label them.
What I remember of their configuration relative to the heater valve and the two vertical connector tubes at the rear of the engine is not what is in the standard Toyota diagram for this truck.
Plus, I slightly crimped the longer of the two thin brass firewall connectors muscling off the hose (before I thought to slice it open with a razor).
My intended fix is to jam the hose on all the way to the firewall past the "stop" ridge and hope it doesn't leak.
So I'm almost back to complete, after buying three aftermarket hoses at my local NAPA store. They are VERY close to original, but not quite the same.
So here are my questions:
1) Of the two connections at the engine block, which is outlet (hotter) and which is return (cooler)?
2) Does the direction of flow through the valve and/or the heater core matter? There's an arrow on the back or underside of the valve, so maybe it does? On a 1938 Packard, it does not matter (for the heater core).
3) In no diagram that I could find, either in the shop manual or online, is it totally clear which of the two longer hoses goes to which of the two connectors on the back of the engine. It's sort of implied by the diagram, but not totally clear. But if you can answer #1, above, that will answer #2 and #3.
Lots of stuff online, but nothing exactly helpful.
Thanks in advance for any suggestions or references.
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