2003 V8 Loosing Coolant

[balong48]

Hello everyone. I have a 2003 V8 Limited 4Runner and I have been loosing coolant for a while now. It was filled by the shop a while ago, and I checked about a month or so later and was down to only a shot glass full. I from there on observed it regularly for about 6 months, and the level never changed. I have recently started looking into the issue more now, and have found that it appears to be below the rubber "straw" that takes in the coolant. Temperatures have been normal. Levels in the radiator appear to be normal as well. It seems like there is not a problem here, but why would I be loosing coolant in the reservoir if the levels in the radiator are fine?

I have just put more fluid in today to fill up the reservoir. Things to note, the water pump was just recently changed with the timing belt (regular maintenance, done 50,000 miles late), so it is possible that the old water pump was leaking a small amount of fluid and that it was burning off.

I did the troubleshooting test to check for combustion by taking the radiator cap off and running the engine without the cap on. No bubbles were seen, however I did see what appeared to be steam coming out of the radiator when the cap was off, and I am not sure if that is normal. Fluid levels rose as the system tried to pressurize and I let the coolant run over for a minute to see if any bubbles were going to appear, but none did.

Is there anything I need to be concerned about? I will be observing the fluid level regularly over the next few days and weeks to see if anything changes. If not, it was the water pump then, as that is the only thing that has been changed since the level has been low.

Thanks!

 

[paraordnance]

I would say its possibly the water pump gasket leak. I had exact same symptoms for couple of years unti I did TB with new water pump and coolant loss disappeared. Are you sure water pump was replaced recently?

 

[balong48]

I am sure the water pump has been changed, the fluid level fell before the pump has been changed. I just put more fluid in yesterday (I had been putting it off for a while). I posted here to see if I should look out for anything else. I am observing the levels now after I put the fluid in.

 

[M1911]

I'm having the exact same issue. I had the timing belt and water pump replaced in December. The dealership says it isn't leaking, but I smell the hot coolant.

 

[ben550]

I too had a coolant leak. While under the truck with a flashlight, I noticed a wet spot under the water pump. The previous owner had changed the timing belt and pump at an independent shop. Took it to a dealer and had them check it, ended up changing the timing belt and water pump with OEM parts. The aftermarket gasket did not fit perfectly and was causing the leak. Once the parts were changed, problem was solved. Take off the skid plate and look up under the front of the engine on the passenger side. If there's dampness around the water pump thats probably your issue. It might not be seated right. FYI I did not have any dripping coolant, nothing on the driveway under the vehicle would have indicated a leak.

 

[cpark_12]

Mine's doing the same thing too! I know exactly where mine is coming from though. We didn't put any gasket where the thermostat housing mates up to the water pump because there wasn't anything there from the factory. I can see a little bit dried pink crust around the top of it. I think I'm just going to take it off and put a little RVT on it and hopefully that'll stop the leak.

Have any of you looked there to see if that's where the leak was coming from??

 

[paraordnance]

the fluid level fell before the pump has been changed

man, I don't know then. Can you see any seepage from under truck? There could be several locations for coolant to leak. It would be hard to diagnose if you can't see where it's coming from. I had no leak prior to TB service but the coolant was always low, no matter how often I top it off. It never overheated but it was always low until I replaced water pump. It must have been evaporating somewhere. When I did TB, I located the spot on the block where my coolant was going. Did you do it yourself? They could have not installed water pump correctly, or tightened bolts too much and crushed the gasket. That water pump gasket is really fragile (aluminum/rubber composite) if I remember right.

 

[DarenS]

Have you checked to see if any bolts are loose which would cause you to lose coolant? If you're losing coolant and it's not in a puddle on the ground, most likely, you're losing it out the tail pipe.

Daren

 

[paraordnance]

Have you checked to see if any bolts are loose which would cause you to lose coolant? If you're losing coolant and it's not in a puddle on the ground, most likely, you're losing it out the tail pipe.

Daren

Thats not always true. I did not had a drop of coolant on the ground, engine block showed no signs of leak, oil analysis show no signs of coolant yet the coolant was disappearing. What I discovered is a little cavity in the block behind a water pump where coolant was leaking and evaporating.

 

[balong48]

I'll try and check all of those things when I get a chance. I'll probably look at some today but it depends on homework and the weather here, it's been rainy lately. I'll see if the fluid level has changed at all since filling it.

 

[Range]

Change the seal. I had the same problem (2004 Runnner) and the seal (don't ask me where it is because I'm not THAT gangster) was just old and worn out like my mother in law. Had it replaced (very inexpensive) and now everything is fine.

 

[M1911]

Change the seal. I had the same problem (2004 Runnner) and the seal (don't ask me where it is because I'm not THAT gangster) was just old and worn out like my mother in law. Had it replaced (very inexpensive) and now everything is fine.

What seal?

I thought that the water pump in particular did not have a traditional gasket, but instead was sealed using a liquid gasket material.

 

[paraordnance]

What seal?

I thought that the water pump in particular did not have a traditional gasket, but instead was sealed using a liquid gasket material.

There is a water pump gasket. It is composite of aluminum and rubber. Some TB kits come with paper gasket. But there is gasket in every kit I seen

 

[Range]

What seal?

I thought that the water pump in particular did not have a traditional gasket, but instead was sealed using a liquid gasket material.

I'll have to go check out the paperwork so I can give you the correct answer as to what and where the seal is.

 

[balong48]

The coolant level still has not gone down since filling it. I just changed all the spark plugs yesterday and did not notice any smell or different look between the plugs. It is starting to seem like the water pump was leaking before it was changed and is no longer leaking.