Help: frustrated another leak post-coolant flush (2 Viewers)

[TankTheLC]

1993 FZJ80

Flushed my system, ran distilled water for a week flushing each day. Finally put coolant in after bypassing phh & bypassing rear heater - then the throttle body hose starts leaking engine side. Cut an inch off the hose and re-attached it as the rest of the hose is in ok condition (not too brittle, not too torn up). A couple days later it just dumps all the coolant, it appears to be leaking here. What hose is this? Is the best solution getting another toyota hose?

In an ideal world I would have just replaced everything on the cooling system so it wouldn’t fail one by one. Not looking for criticism, looking for solutions.

Edit: my suspicion says thats the top of the throttle body hose - but asking for some more input here. Can’t exactly tear it down as I’m back to working all day again.

 

[graham5david]

Looks to be from the throttle body coolant hose. It can be deleted until you get time to replace it. Just cap it coming off of the block and cap the return that comes into the thermostat. If you live in a warmer area you don't need it. If you are worried about it then you can order the lines from @NLXTACY on wits end website and replace them when you have time. It seems like it would be easiest just to remove the throttle body to get to it from the top and run it down from there. Then reach up through the wheel well to attach to the block.

 

[graham5david]

Here is a good write up on it.

Rear Heater Delete/Coolant Line Cleanup

I just wanted to give a quick picture tutorial on how I cleaned up my heater and coolant lines under the hood. On my '93, this method reduced the number of heater hose connections from over 50, to about 10. It also makes the whole system much more simple. This method requires deleting the rear...

forum.ih8mud.com

 

[TankTheLC]

Looks to be from the throttle body coolant hose. It can be deleted until you get time to replace it. Just cap it coming off of the block and cap the return that comes into the thermostat. If you live in a warmer area you don't need it. If you are worried about it then you can order the lines from @NLXTACY on wits end website and replace them when you have time. It seems like it would be easiest just to remove the throttle body to get to it from the top and run it down from there. Then reach up through the wheel well to attach to the block.

View attachment 2063936

View attachment 2063937

I really appreciate it and I've considered it. Those caps aren't intended for coolant and the cost of the oem isn't that expensive. I will probably order the wits end kit when I calm down.

I actually drove the truck for 2 hours around town and on the highway after it started leaking - didn't even drain the reservoir. Didn't leak at all every time I parked and truck ran at normal temperature. No idea why it would leak and not leak but I guess I have some limited time on it. Honestly about to just replace all of the radiator hoses and be done with it. I'll update this thread when I finally get around to this project.

 

[graham5david]

I was just thinking of a short term solution until you get around to it. I think if it was a permanent bypass then using some quality coolant lines would be better.

 

[TankTheLC]

For anyone who might find this useful in the future, these weird small hoses are referred to as bypass hoses and yields much more results on the forums. I managed to find this diagram which clears things up. The hose in question is the no. 1 bypass hose.

 

[graham5david]

1FZ-FE Engine Little Hose Kit

1FZ-FE Engine Little Hose Kit (SHK-1)

absolute-wits-end.com