coolant leak (random)

[takumi]

In the last few days there seems to be a coolant leak coming from under near the bell housing, or it looks like that's where it's coming from. It's dripping off the dust cover shroud thing under the 4runner. (3.4L v6)

So i'm trying to figure out where the leak is coming from. I don't see any coolant coming from the thermostat housing. However i see the leak when I rev the engine for about 20 seconds.

Once I stop revving the engine and just let it idle, it stops leaking. Also it seems like the cooling system is not building up any pressure. I slowly removed the radiator cap after the engine had been running for 20 minutes with the A/C on and it warms up completely, but the cooling system is not building up pressure.

Weird thing is the engine is not overheating, it's running at normal operating temperatures.

Does this sound like the water pump going bad and or leaking?

 

[nissanh]

Remove the skid plates and check. Wear goggles: don't want hot coolant going into your eyes. Post a picture or two.

 

[Brilliant]

AC drain?

 

[takumi]

yeah, i see the a/c drain. it's dripping at the back of the engine as well. The a/c drain is dripping. The leak I'm referring too is rusty colored water. I'm positive it's a coolant leak somewhere in the system. Just gotta find it.

AC drain?

 

[A.Wilson013]

yeah, i see the a/c drain. it's dripping at the back of the engine as well. The a/c drain is dripping. The leak I'm referring too is rusty colored water. I'm positive it's a coolant leak somewhere in the system. Just gotta find it.

Rusty colored water is probably not coolant, my friend.

Atleast, I hope it isn't.

 

[Brilliant]

pictures might help. Check under your carpets, see if your heater core is leaking.

 

[Jas2171617]

Check reservor coolant loosing any? If level still the same it may not leaking. If loosing, pay attention at water pump.

 

[gamefreakgc]

Rusty colored water is probably not coolant, my friend.

Atleast, I hope it isn't.

It is if that coolant is burnt beyond all reason. But then the leak is the least of his worries.

 

[takumi]

just an update to this thread

I decided to attempt to flush the radiator with blue devil radiator flush. the instructions said to turn the heater on full blast and let the car run for about 10-20 minutes. Well i followed the directions and while i was running the heater i could not figure out why i was not getting any hot air or heat coming from the vents.

i removed the skid plate, but can't see where the leak is coming from. The floor of the 4Runner has weather tech floor mats. I bought the truck used, knowing i was going to have to do a little work to it. I'm beginning to think the leak is coming from the heater core.

If it's the heater core, how do i bypass the heater core? I assume you get a hose to bypass it, but what hoses do i remove and what points or where do i install the bypass hose?

Thanks guys for your help

 

[MStudt]

If it's the heater core, how do i bypass the heater core? I assume you get a hose to bypass it, but what hoses do i remove and what points or where do i install the bypass hose?

Thanks guys for your help

Why would you want to bypass the heater core?

Another thing you might want to check would be the rear heater lines. The run down the passenger side, and are known to fail. A lot of people will remove these lines all together.

 

[takumi]

i guess i thought if the leak was coming from the heater core, if i bypassed it, that would stop the leak for now. and then i could decide if i wanna look into replacing the heater core.

so these rear heater lines you speak of, where would i find more info on where to locate them and how to remove or bypass them?

thanks for your help

Why would you want to bypass the heater core?

Another thing you might want to check would be the rear heater lines. The run down the passenger side, and are known to fail. A lot of people will remove these lines all together.

 

[MStudt]

i guess i thought if the leak was coming from the heater core, if i bypassed it, that would stop the leak for now. and then i could decide if i wanna look into replacing the heater core.

so these rear heater lines you speak of, where would i find more info on where to locate them and how to remove or bypass them?

thanks for your help

The passenger side of your engine compartment you'll see 2 hoses connecting to 2 metal tubes. The tubes will have a 90 degree bend on them, and they're side by side. They run down the firewall, along the frame rail, and the up into the cab under the passenger seat. Sometimes there's an aluminum cover over the lines on the frame rail. They should be the only thing on the passenger side frame rail.

Here's a write-up.

 

[Doc2012]

Just going to throw this out there:


1) You're not getting heat, so that leads me to believe thermostat.

2) Rusty colored water, from the bell housing area? This leads me to believe the fron seal of the transmission has gone bad, therefore leaking transmission fluid.

I could be wrong, but as far as water leaking from the bell housing area, the only real way that would happen is if the heater lines were bad. If that were the case, the truck would be loosing coolant, and be overheating, because of the system being pressurized. If it wasn't running, a small drip would be explainable, but with the truck running and system pressurized, that leak would be quite a bit more noticable, and you'd be able to smell coolant burning, along with the temp increasing.

Dead Center of the fire wall is the heater valve. Check for leaks from this area.

Replace the thermostat in order to have heat returned to the vehicle.

 

[takumi]

I followed the thread for the leaking heater element. that was for a 1997. mines a 1999 limited. I figure both are the same, but i don't see the same metal lines where he bypassed the rear heating element, like under the hood of the 1997

i posted pics. I can tell there was a leak at one time. under the hood has residue from a previous leak. i ordered a oem thermostat and oring

the leak is not consistent. i drove it this morning for a few miles. i turned the heat on. i did begin to feel some heat coming from the vents, and it was leaking again. it's leaking near the bell housing, so it may be that rear heating element. i just gotta locate the lines to it, so i can try bypassing it

 

[MStudt]

I followed the thread for the leaking heater element. that was for a 1997. mines a 1999 limited. I figure both are the same, but i don't see the same metal lines where he bypassed the rear heating element, like under the hood of the 1997

i posted pics. I can tell there was a leak at one time. under the hood has residue from a previous leak. i ordered a oem thermostat and oring

the leak is not consistent. i drove it this morning for a few miles. i turned the heat on. i did begin to feel some heat coming from the vents, and it was leaking again. it's leaking near the bell housing, so it may be that rear heating element. i just gotta locate the lines to it, so i can try bypassing it

They would go down right where that open hole is next to the ground wire. So that's not the culprit then.

 

[takumi]

thread update...

good news is, the leak is no longer random, it leaks consistently now. not so good news is, i can't seem to find where it's leaking coolant.

I initially thought it was the heater core, so i bypassed the heater core, and it's still leaking. it seems to be coming from the backside lower throttle body area, but i cannot be sure. If i stand in front of the engine and look under the throttle body i can see it dripping coolant on the fuel injector under the throttle body. I tired removing the back air box assembly that goes between the throttle body and the mass air sensor to get a better view of where the leak is while the engine is running, but the engine will not run with the black air box assembly removed.

any suggestions on where the leak is coming fro or how i can locate the leak?

 

[Norwester]

There are coolant lines on the throttle body front and back. Most likely thats where its coming from. Check/replace them.

 

[takumi]

i may also have the 2 lines on the back of throttle body in the wrong places, because i did not mark where they go before i took it apart to change valve cover gaskets

is there a thread on changing those coolant lines on the throttle body, so i know where they go?

are these lines / hoses something i get at the dealership or at any automotive parts store?

There are coolant lines on the throttle body front and back. Most likely thats where its coming from. Check/replace them.

 

[takumi]

i appreciate the help

i found the source of the 2nd coolant leak. one of coolant lines on the back of the throttle body had a split it. i replaced it and let it run for about 20 minutes. so far i have not seen a leak.

also i believe the original random leak was from the heater core. i have bypassed the heater core, so i will know in a few days, if the leak does not come back then that was the original problem

thanks again everyone that responed. it is much appreciated

There are coolant lines on the throttle body front and back. Most likely thats where its coming from. Check/replace them.

 

[Jbarret]

Coolant Leak

I have had this coolant leak for a couple of weeks, and have had a recent water pump and timing belt change months prior. I track it to this area where the metal rod that supports the alternator connects to the engine. I just need help identifying what this part is called and if it's an easy fix or not. I have a 99 3.4 2wheel drive by the way.