[wh0wants2know]

One of my ISC coolant lines blew up this morning. I'm not sure which one for sure, so I'm just going to replace all of them. Having searched the forums, I have locted ample information about how those hoses are routed so I know precisely where they go and their part numbers even (n00bs: learn from my example). Now, my questions are as follows:

1. do I need to order the special pre-shaped hose from toyota or can I just buy some 10mm hose and run it?

2. If I do need pre-shaped hose, can I get it anywhere other than toyota (NAPA, Carquest, etc? they are not usually known for having stuff like this. . .)

3. I read something in my search about bypassing the coolant hoses to the ISC but I didn't find any specifics, is it possible to do this, how is it done, and what are the pros/cons to it?

 

[flubyux2]

dont put them back on.

if you can, loo under the intak emanifold. there is a coolant nipple on the bottom of the LIM between runners 1 and 2. then there is another coolant nipple stemming from the rear coolant pipe. its held by a brace and bolt to the block, below #5 runner i think. take a piece of 10mm/3/8" ID hose and join these 2 nipples together. itll bypass the TB and ISC coolant lines.

keeping the hot coolant out of your ISC and TB will allow the intake and TB to stay that much cooler. youre not pre-heating your manifold and TB anymore. so the only heat getting into the manifold is thru natural conduction from the head. but during cruising, the air running thru the manifold and TB will actually cool it off and lower your intake air temps. i noticed this because after i did this mod, my car would idle at 1200 after getting off the freeway because the ISC thought the car wasnt warmed up yet; the intake manifold had COOLED off to well below the coolant temp.

 

[shaeff]

i've had mine bypassed for some time now. no problems here.

-shaeff

 

[selz202]

http://oldschool.supracentral.com/htm/tb.htm

 

[flubyux2]

yeah, i was actualy putting the 1jz back together last night and did all this. i went so far as to pull the nipples out of the throttle body and the ISC for a cleaner install. they are only pressed in, so if you grab a pair of vice grips and clamp down, just twist back and forth and they will work free. the ISC nipples are differnt though. they have a collar w/ a tab brazed onto them. so youll have to twist a bit harder. itll work its way out a little bit, so if you grab a flat head screw driver, you can pry that tab up out of the way so the nipple can rotate, unhindered.

 

[[email protected]]

And what do you block off the resulting hole with, Flub?- Do you weld them shut, or tap some threads into them? LMK.

 

[flubyux2]

the vacant holes on the TB and the ISC? nothing... if theres no coolant going into them, theres nothing coming out of them. they dont lead into the intake manifold or create a vaccume leak... if they did, thatd mean that coolant was getting INTO your induction system, and youd have bigger problems than rerouting coolant lines.

 

[selz202]

Ya know... i just now realized that, heh even Larry A capped them off from the looks of it.

Tim

 

[crazysupra2JZ]

I thought about the same thing when I took my coolant lines off....I was like man should I block these off or something