R32 coolant leak from small hose

[nouveau_poor]

So I drove out to my local gas station this evening to top up my R32 GTR and then drove back home, temp reading was normal. Somewhere along the way home I sprung a coolant leak and when I checked under the car in my garage I found a small puddle forming under the pulley/belt area at the front of the engine. One paper towel to catch the drips was enough before the leak stopped.

I then started up the car again and looked, nothing new was leaking out.

I then drove back to the gas station to try to recreate/diagnose the problem. There was no spill at the stall I used and it couldn't have been cleaned since it was late and nobody was working there, so it must have happened on the drive home. I looked under the car again with the engine running, and no leaks. But when I turned the engine off, the leak started again. Poking around the engine bay I'm 97% sure the leak is coming from the little bit of hose shown in the pictures, right in front of the cam cover under the plastic bracket thing that covers the angle sensor wire. Nothing unusual I could point at on the original drive home that could have caused it, so I'm thinking it must have just been on its last leg. 

When I drove back home, I let the car idle to cool down while watching underneath the car. As the engine cooled while idling, little drips started to come out very slowly, increasing the longer the engine was left to run. I let the engine shut off, and immediately placed some paper towels under the little hose. Checked under the car as the towel turned greenish with coolant and I didnt see any of the drips I saw before. So I'm thinking that the drips from higher up were dripping from the pulleys down onto the floor

My questions: What does this hose do? I figure it's something to do with coolant flowing through it as the engine cools down, like a reroute. Once the engine cools down in the morning, can I just remove the two clamps and replace it with a length of new hose, or would that result in coolant pissing out? Is this hose anything special that I would have to buy OEM, or can I go out to the local auto shop and ask for 3 inches of hose of matching diameter? Thanks all.

 

[niZmO_Man]

It's just coolant hose. If you can get same internal diameter and similar shape, change it. it's probably cracked under the clips.

[Duncan]

Also, if the hose is OK, it might just need a proper hose clamp instead of a 30 year old spring clamp. 

Not exactly sure what the hose is but I think turbo water feed or return.

[jmknights93]

You're problem may just be the spring clamps. But I've attached a diagram for you.

https://www.amayama.com/en/part/nissan/1405505u22

[MoMnDadGTR]

that diagram is the one you want it is the same as the one in bnr32 manual. I had this exact leak I replaced the line didn't fix it, through a new clamp on from princess auto and fixed. its the water line for the turbos. I replaced line after line on my 93 gtr before I said fak it and replaced all the coolant and vacuum lines car never ran better. I would replace the hose and the clips I got all my stuff from terra firma and kudo. If you haven't already done it, while you have the coolant dropped on the car I would replace the 2 small coolants sensors one for the gauge and one for the engine while you have the coolant out, as well as the thermostat while you got it apart just make sure you install it right. sometimes a plugged up coolant system causes these leaks. my radiator was completely plugged up as well from 30 years of what ever.....hope this helps mate.

[nouveau_poor]

Think I got it sorted out today. Getting the hose off was testing my patience as it was bloated in the center, so getting the spring clips past the little nozzle "nub" area was damn near impossible. Resorted to cutting it off with a razor. Found the source of the leak, there is a tiny split on the rear of the hose that wasn't visible when still on, and matched the location of where the drips were coming from. See below.

Went to the auto shop and got a length of hose for a few dollars and new screw type clamps. The old spring clamps still seemed strong and ok but why not get new hardware if I'm already at the store. 

Learn from my mistakes if you end up reading this thread and have the same issue. I dont know if there is a way to avoid this short of draining all your coolant beforehand, but there will be coolant in this hose and the tubes it connects to. So when you slip it off (but you'll actually cut it off) the coolant will start leaking out. I have a sizable puddle of the stuff on the garage floor that I still have to clean up. Paper towels might help to soak up a bit but if you can get a container of some sort to squeeze in that narrow space to catch it until it stops, that'd be best. 

Secondly, if you don't get the molded Nissan hose for 25-30ish dollars and get plain hose like I did, do not cut the plain hose to the same length as the original hose. I did that the first time and even with the slight bend/curvature due to the hose coming off the roll, it's not the same as the OEM. What this will result in, is that there will be a rather sharp bend causing the center portion of the new hose to bow out, as though it were being pinched, once it's on since the two nozzles the hose joins are rather close together as in the photos. I was afraid that this bowing was decreasing the inner diameter of that area and could lead to higher pressure so I took it off. Adding insult to injury, even after trying lubricant, the only way I could get it off was to cut it off again since the work space is so small. What you'll want to do is cut the hose to a bit shorter than the original. By doing so it'll allow both sides to connect but still allow room for the hose to "push" further along the nozzle so the sharp bend/kink doesn't occur, with plenty of room behind the nozzle nubs to clamp down on.

Will be getting an alignment done in the next day or so for some suspension work I did recently and I'll have them top off the coolant I lost and bleed the system, as I'm pretty sure that there is some air in there after removing the hose. Happy Easter

[nouveau_poor]

10 minutes ago, MoMnDadGTR said:

that diagram is the one you want it is the same as the one in bnr32 manual. I had this exact leak I replaced the line didn't fix it, through a new clamp on from princess auto and fixed. its the water line for the turbos. I replaced line after line on my 93 gtr before I said fak it and replaced all the coolant and vacuum lines car never ran better. I would replace the hose and the clips I got all my stuff from terra firma and kudo. If you haven't already done it, while you have the coolant dropped on the car I would replace the 2 small coolants sensors one for the gauge and one for the engine while you have the coolant out, as well as the thermostat while you got it apart just make sure you install it right. sometimes a plugged up coolant system causes these leaks. my radiator was completely plugged up as well from 30 years of what ever.....hope this helps mate.

Thanks, this was the route I was going to go when I replace the radiator with a Koyo. Wanting to do the radiator, hoses, belts, pulleys, and probably fan in one go.

[MoMnDadGTR]

nice work mate, good job on following through with the photos to makes things way easier to help.  Good call on doing the whole system when you do your rad. just a note.....maybe water pump, timing belt, pulleys and tensioner bolt when you do radiator. sure you already knew that. when you pull the crank pulley off make sure you have a proper puller or it will damage it other than that its a pretty easy job.  some water pumps use a gasket some just Permatex seal.  make sure that coolant system is bled good in meantime, stay safe mate. 

[BK]

FYI that hose is the turbo coolant RETURN. The top radiator hose is also the return from engine to radiator.