bypassing heatercore

[enjoi.this]

I looked around all over the place trying to see how some people have bypassed the heater core on a 7mgte. What I found for info was to connect the two coolant pipes at the back of the head. But my dilema is that there is three. The Line coming out of the top of the engine goes to the denso sensor, then into the firewall. Then the other two on the passenger side of the motor connect together. I cant put the hoses back on because half of the hoses I took off were rotten :3d_frown:
If some one could elaborate on this I would greatly appricieat it. This is really getting to me...

 

[gaboonviper85]

get new hoses...

 

[Justin]

get new hoses...

No frickin kidding. They're pretty reasonable through Champion Toyota.

 

[92TealSupra]

Just replace the hoses, I looked up the cost, and they should run for then 70.00 for all three.

 

[enjoi.this]

Just replace the hoses, I looked up the cost, and they should run for then 70.00 for all three.

Yes I will replace the hoses, but that still doesnt bypass the heater core. Its pooched out. Anyone have an idea?

 

[Rennat]

http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=CO&P=2

connect "to heater" to the "from heater" with a NEW hose... is that really hard?
but the heater core is another place for the heat to escape from... so i dont see why you just dont fix the heater core instead...

 

[CzA]

OK this is going to be extremely non technical as im not too sure if i know name for the item i am about to speak about. My heater core is done, and leaks very badly. So, under the hood there is what I believe is a bypass valve, just near where the charcoal canister is. What i did was remove the vacuum hose from it, and it bypasses the heater core ( you actually see a vlave / or switch pull down when the hose is removed). I have no heat now, but i am about to park the car for the winter so what do i care. It fixed the problem, no leaks and i save a lot coolant.
Now if what i said does not make sense, or i have the incorrect info on what it is i did exactly, please experts correct me. I know this is the tech area, so come correct or don’t come at all. I try....
Thanks...

 

[Rennat]

if you "bypassed" the switch it would be how i said, but you just closed the valve, essentially cutting off the coolant from the heater core. which isnt the best way to do it... but it gets the job done.

 

[CzA]

if you "bypassed" the switch it would be how i said, but you just closed the valve, essentially cutting off the coolant from the heater core. which isnt the best way to do it... but it gets the job done.

How come this isn’t the best way to do it? Am i hurting my system in any way? I didn’t know there would be any draw backs from doing this (aside from no heat), and i don’t like knowing i could be harming the system.

Thanks.

 

[Rennat]

if you look at the link i posted, it shows the flow diagram of the system. the coolant goes throug the back of the head (cooling off the back of the head) and the front by the thermostat housing. if you have hot coolant just sitting there, and nowhere to go but the opposite way of where its being pushed, you'll create a hot spot in the back of the engine.

you want to make the coolant system flow as easy as possible, so you should take the to heater those, and plut it into the from heater those to help with the flow through the back of the head.

the hose would cost like $4 and the amount of coolant you would lose you could replace from the hose... just be fast witht he hoses, or clamp them of when you work on them.

 

[enjoi.this]

Well its all good now, I bypassed the heater. I would replace the heater core but its winter now and I am parking the car this week. Same as what CzA is doing.

 

[Who]

if you look at the link i posted, it shows the flow diagram of the system. the coolant goes throug the back of the head (cooling off the back of the head) and the front by the thermostat housing. if you have hot coolant just sitting there, and nowhere to go but the opposite way of where its being pushed, you'll create a hot spot in the back of the engine.

you want to make the coolant system flow as easy as possible, so you should take the to heater those, and plut it into the from heater those to help with the flow through the back of the head.

^^ Is that true? No disrespect intended. When I look at the flow chart I see that the coolant flows through the block or the back side of the head and then out through the heater union. Regardless if the coolant goes through the heater core or not the coolant always flows through the back of the block and out of the heater union first. When the heater valve opens the coolant flows through the block out the heater union, through the heater core and exits and connects to the pipe that runs across the back of the engine and around to the front. If the heater valve is closed the coolant flows through the back of the block exits at the heater union making the 90deg. turn to the 90deg. coolant hose (that spills all your coolant out in 5 seconds flat) to the front of engine.

If Toyota included the heater core as part of the cooling of the engine block than setting your ac panel temp at 65deg. is dumb arse idea. I know Toyota was and is a hell of a lot smarter than that.

 

[Rennat]

i feel kinda dumb... cause i honestly never saw the pipe leading from the heater union bolt in the diagram... but i still stand by my statement that its better to have the "to heater" to the "from heater"... unless you weld shut the union....

nice catch. im usually online when im half asleep, so my bad... haha