CLightning

So I recently blew a heater hose (intake manifold to heater valve) luckily only 2 blocks from my house and was able to limp the car back home without the need for a tow truck. This was wake up call for me to inspect and replace every single coolant hose on my '93 daily driver with 220,000 miles on the clock as a preventative maintenance. The last thing I need is to get stranded on my dreaded bumper to bumper, 97 degree weather, 30 mile commute to work in Los Angeles. I've already replaced the upper and lower radiator hoses and all the heater hoses using a mixture of molded and generic flexible heater hose, but I was wondering about the TB coolant lines:

1. Anyone know what size hose the TB coolant lines are? (I'm afraid to remove the old hose and destroying it in the process only to find out no one in town carries that size hose!)

2. Can I use generic flexible coolant hose without routing problems or stick with the molded stock hoses (if they still exist)?

3. Does the "TB Bypass" mod really work? Will this MOD fail a visual inspection for a smog test in CA?

4. Any tips to remove the dreaded driver side TB coolant line without destroying something else?

5. I think I covered all the coolant hoses- upper and lower radiator hose, heater hoses, TB "water bypass" hoses, radiator overflow tube. Am I missing anything else?


Thanks in advance.

1JZPWRD

iTrader: (59)

IACV also has a coolant hose. Also do all the vacuum hoses while you have everything apart.

grumpi300

iTrader: (1)

I recebtly bought that hose under the throttle body from lexus. No more than $35 if I recall correctly. I have the 92 sc300. That hose goes through all kinds of different bends and twist so I would recommend molded.

Ali SC3

iTrader: (10)

1. You can get that size at any auto store, i think it is a 1/4 but I may be wrong it isn't special though.

2. Yes, its just a coolant hose.

3. yes it really works, you can either use a new hose to connect the 2 hoses together to bypass it, or you can stop the flow entirely by taking both hoses and blocking the flow at both ends. on a stock vehicle I would just replace the hoses with dealer parts from toyota just tell them you have a 94 supra non turbo it will be less expensive than lexus. you won't gain much by bypassing it on a stock motor.= so I would just replace it and you could use universal coolant hose it will just be a little harder to work with.

4. long needle nose pliers are your friend, I assume you mean the one on the throttle body. sometimes it helps to get the throttle body unbolted before you disconnect the hose and slide it off till the hose is pulled tight, and then you can get a much better angle on the spring clip and then just pull it off.
If you mean the one under the intake, then I am not sure what all you have to take off to get to that one.

5. thats about it.

1JZPwRD on the n/a there is only one coolant line that goes through the throttle body, since the IACV is part of the throttle body it isn't one after another like it is on the gte intake. warming an idle air control valve is over engineering if you ask me but it all does add to reliability.

CLightning

Lots of great info here guys -thanks!. I'll go pick up some new vacuum tubes and go ahead and order a TB to radiator coolant hose for a '94 n/a supra