Coolant leak? (1 Viewer)

[Oogabooga]

Started noticing over the past couple months very small amounts of what I assume is coolant on the underside front passenger side of the vehicle. Could be a coincidence but around the same time a few months ago I noticed the coolant reservoir was low and topped it off (first time since getting the truck mid last year). Today the coolant reservoir looks to be around the same level as it was pre top off.
However it is unclear where the leak is originating from, all I can ever see is a few drops spattered on the underside.

 

[CanadianRockyCruiser]

Check your water pump for leaks and coolant crystals.

 

[ryanCA]

Waterpump
Radiator
Valley Plate
Head Gasket

 

[Oogabooga]

Doesn’t seem like it’s the radiator, top does not show any crack at the normal spot, and bottom of the radiator itself seems clean.

Checked what I believe is how to check the valley plate and it looks clean also. (Had to remove some of the foam and it just kinda disintegrated, anyone know if it’s important to be replaced?)

Having difficulty getting a look at the water pump, watched a video but the location is still unclear and I can’t quite ID it behind all the belts and pulleys, but I don’t see any obvious coolant leaks or dried coolant.

Not sure there is a way to check for a head gasket leak easily? I don’t notice any smoke or exhaust coloration from the vehicle, other than normal exhaust when it’s cold out and the engine hasn’t warmed up yet. But I would think if that were the case the the coolant wouldn’t be leaking down to the bottom of the vehicle as it would leak into a cylinder or into the oil right? I also didn’t notice anything off about the oil on the last change a couple months ago, which was when I noticed the coolant leaking for the first time.

The leak appears to be very small, I drove the car yesterday a bit and got to up to temp, and there does not appear to be any more coolant on the bottom this morning after wiping it up yesterday.

Side note, is the pipe in the last photo supposed to just be open like that? Seems like there should be a cap?

 

[CanadianRockyCruiser]

There's supposed to be a cap. That's a refrigerant port for the AC unit.

I think you'll want to look at your water pump. It's not a huge deal to have a bit of a coolant leak, but it's not that hard to replace (if that's the culprit). Leaks on the water pump are most obvious when looking from the bottom, but a cell phone photo can be a useful inspection mechanism too.

Valley plate leaks are a bit tough to find without removing the intake manifold, since the leak can occur at almost any spot on the valley plate and access is very limited. A boroscope camera is helpful.

 

[Oogabooga]

There's supposed to be a cap. That's a refrigerant port for the AC unit.

I think you'll want to look at your water pump. It's not a huge deal to have a bit of a coolant leak, but it's not that hard to replace (if that's the culprit). Leaks on the water pump are most obvious when looking from the bottom, but a cell phone photo can be a useful inspection mechanism too.

Valley plate leaks are a bit tough to find without removing the intake manifold, since the leak can occur at almost any spot on the valley plate and access is very limited. A boroscope camera is helpful.

Thanks, I’ll have to try and find the part number for the cap then and hopefully get it soon, leaving for a road trip down the west coast in a week. Would it be insane to just like tape it over for the time being until I source a cap, or use some pvc shrink tubing to seal it? I’m assuming it’s been missing since I got the vehicle about 9 months ago. Never noticed.

I’ll have a look at the underside again and see if I can’t locate it then, also ordered an endoscope that will come late today.

 

[linuxgod]

Not sure your mileage but if it’s on the passengers side front and you’re over 100k it’s almost certainly the water pump

 

[Oogabooga]

Not sure your mileage but if it’s on the passengers side front and you’re over 100k it’s almost certainly the water pump

Yup it’s on the passenger side only and the spatter does appear to be perfectly lined up with the hose going up from the bottom of the radiator to what I assume is the water pump. 105k miles. But again I don’t see any obvious signs of leaking from anywhere higher up, it’s only on the very bottom of the vehicle.

 

[bloc]

Consider getting an inspection mirror from an auto parts store. The water pump pulley is the black one, about 4-5” in diameter, and has 4x 12mm head silver bolt heads visible on the front face. You can see it with two bolt heads visible in your last photo. It is not the pulley that the fan clutch attaches to.

With the inspection mirror and a flashlight you can see the back side of the pulley, where you’ll likely have some pink crystals from dried coolant.

 

[Oogabooga]

I took a look behind that pulley and everywhere I could think with a borescope and I’m not seeing anything at all. But just based on the location of where the coolant is appearing I agree that the water pump makes sense, just baffled I can’t find the source. At least the leak appears to be extremely slow so hopefully I’m fine for a while until I can just go ahead and replace the water pump and probably just do the updated radiator at the same time. I didn’t take much coolant to top it back off to where it was several months ago and my temps are completely stable while driving.

 

[OregonLC]

Is it temperature related? I once had an issue on the 100 where I was adding coolant frequently but couldn't find the source. In that case is was a pressed in plug on the throttle body that would steam when hot (and eventually catastrophically fail). Point being, letting it idle for 20-30 minutes to get it fully hot. Rare, but there could be a leak only happens when it heats up and expands.

 

[Oogabooga]

Is it temperature related? I once had an issue on the 100 where I was adding coolant frequently but couldn't find the source. In that case is was a pressed in plug on the throttle body that would steam when hot (and eventually catastrophically fail). Point being, letting it idle for 20-30 minutes to get it fully hot. Rare, but there could be a leak only happens when it heats up and expands.

Not sure, the coolant temp hovers between 185-195 which I think is the normal range. I have a scan gauge mounted and always pay attention to it. It’s never gone above 200f.

 

[OregonLC]

Not sure, the coolant temp hovers between 185-195 which I think is the normal range. I have a scan gauge mounted and always pay attention to it. It’s never gone above 200f.

Not suggesting that it's overheating. But that if you're not finding the leak when the truck is off/cold try looking for it when running/hot.

 

[CanadianRockyCruiser]

There is a "weeping hole" on the water pump. It is a common source of coolant loss. A new waterpump and gasket will fix this, but it is not usually catastrophic until the gasket fails and she's gushing coolant. I would replace the water pump and gasket. Consider the thermostat and pulleys "while you are in there".

I replaced my water pump on my 2013 lx at 180,000 km. It was exhibiting similar leakage to yours.. the new OEM part number had a slightly different design. No leaks since.

 

[Oogabooga]

Not suggesting that it's overheating. But that if you're not finding the leak when the truck is off/cold try looking for it when running/hot.

Ahh I gotcha, yeah I’ll keep this in mind then and see if I can’t find it while the engine is at temp instead.

There is a "weeping hole" on the water pump. It is a common source of coolant loss. A new waterproof and gasket will fix this, but it is not usually catastrophic until the gasket fails and she's gushing coolant. I would replace the water pump and gasket. Consider the thermostat and pulleys "while you are in there".

I replaced my water pump on my 2013 lx at 180,000 km. It was exhibiting similar leakage to yours.. the new OEM part number had a slightly different design. No leaks since.

View attachment 3866714

Thanks. I’m pretty confident it is indeed the water pump, it must be, and will definitely replace it soon. And yeah I plan to replace as much as I can while I’m there, it’s just a matter of finding the time to do the job. Unfortunately I just placed and order from Toyota last week for a couple other things while they were running their 25% off sale, wish I had dug deeper into this leak earlier and got everything in one shot. Hopefully it lasts me a couple months before the “catastrophic failure”.

 

[CanadianRockyCruiser]

Ahh I gotcha, yeah I’ll keep this in mind then and see if I can’t find it while the engine is at temp instead.

Thanks. I’m pretty confident it is indeed the water pump, it must be, and will definitely replace it soon. And yeah I plan to replace as much as I can while I’m there, it’s just a matter of finding the time to do the job. Unfortunately I just placed and order from Toyota last week for a couple other things while they were running their 25% off sale, wish I had dug deeper into this leak earlier and got everything in one shot. Hopefully it lasts me a couple months before the “catastrophic failure”.

It will probably last you for a few years before catastrophic failure...just keep an eye on your coolant level. Coolant leaks are a slippery slope. It happens slowly, and then all at once, resulting in high temperature, overheating, more pressure, more leaks, head gasket failure, seized engine.

 

[Oogabooga]

It will probably last you for a few years before catastrophic failure...just keep an eye on your coolant level. Coolant leaks are a slippery slope. It happens slowly, and then all at once, resulting in high temperature, overheating, more pressure, more leaks, head gasket failure, seized engine.

Sweet, yeah I will likely do it this summer so not that far down the road. Will keep a jug of coolant in the vehicle and I already constantly monitor temps.

Do you happen to have a list of the parts for the water pump replacement you used. Found a couple threads but there does not seem to be an agreed upon comprehensive list of parts. Some places mention the thermostat and other have a water inlet pipe which includes a thermostat instead. A water outlet housing gasket is mentioned in a guide video but not on any list (cheap so whatever). And also the “best” list I’ve found has a fan bracket assembly (16380-0S010) which is a $220 part but I don’t see it mentioned anywhere else.

 

[Sandroad]

Sweet, yeah I will likely do it this summer so not that far down the road. Will keep a jug of coolant in the vehicle and I already constantly monitor temps.

Do you happen to have a list of the parts for the water pump replacement you used. Found a couple threads but there does not seem to be an agreed upon comprehensive list of parts. Some places mention the thermostat and other have a water inlet pipe which includes a thermostat instead. A water outlet housing gasket is mentioned in a guide video but not on any list (cheap so whatever). And also the “best” list I’ve found has a fan bracket assembly (16380-0S010) which is a $220 part but I don’t see it mentioned anywhere else.

Post #16 in this thread has a fairly complete list of part numbers. Your choice on how crazy you get!

150K mile PM

So I'm at 150K miles on my 2013 200. I'm the second owner and bought it in 2015 with about 40K miles. I've done all of the recommended maintenance stuff and before I owned it, it was dealer maintained but am wondering if it would be worth it to replace the water pump, hoses and belts just to...

forum.ih8mud.com

 

[Oogabooga]

Post #16 in this thread has a fairly complete list of part numbers. Your choice on how crazy you get!

150K mile PM

So I'm at 150K miles on my 2013 200. I'm the second owner and bought it in 2015 with about 40K miles. I've done all of the recommended maintenance stuff and before I owned it, it was dealer maintained but am wondering if it would be worth it to replace the water pump, hoses and belts just to...

forum.ih8mud.com

Thank you, looks comprehensive. This list still has the fan pulley mounting bracket too, just seems strange that it would need to be replaced also… unless it’s just prone to breaking but it is a fairly expensive part.
Thanks

 

[OregonLC]

The fan pulley bracket is a 200k part, and, yes, isn’t cheap. Just depends on how much you value your time ‘while you’re in there’.