So i have adopted the Family Yukon which is my favorite truck my parents had. Already replaced the pickup tube since i had bad Oil Pressure and now shes good however i noticed a leak of the coolant coming from around the water pump area. Ive been chasing it down and come to the conclusion the pump was starting to fail, however today this morning no wet spot under the truck. i check resi and she good after i topped off the previous day. she only lost about a litter or so over the 3-4 days i saw it dripping. I got home from work and went ahead and checked it while it was running and at temp so i know it has pressure and everything is dry now. I havnt done anything to the truck the leak just stopped? Im thinking its gaskets waring but i feel like it would show that under pressure. Any tips for my diagnosis while im checking it in the morning? The Truck has been converted to electric fans years ago so i have plenty of room in the hood thankfully
*fixed*Antifreeze leak present for 3 days gone the next
- Thread starter OGManBug
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Welcome to the Forum from NH.
Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.
I hope that you will become a participating member in the Forum's discussions.
Pics of the truck, please.
If you were losing a liter of coolant every 3-4 days, and you have confirmed that you do NOT have any coolant leaking ELSEWHWERE on the truck, then I'd recommend replacing the water pump, the gaskets, and the thermostat. IMO, it is highly unlikely that the leak that you identified has stopped for good.
Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.
I hope that you will become a participating member in the Forum's discussions.
Pics of the truck, please.
If you were losing a liter of coolant every 3-4 days, and you have confirmed that you do NOT have any coolant leaking ELSEWHWERE on the truck, then I'd recommend replacing the water pump, the gaskets, and the thermostat. IMO, it is highly unlikely that the leak that you identified has stopped for good.
Welcome to the forum, from Oregon. Hopefully you will learn to ALWAYS post the vehicle info, instead of us guessing all the time. "Family Yukon" leaves me in the dark.
Look for the corrosive stain from the weep hole, that will show a water pump leak, which is likely what you have.
Look for the corrosive stain from the weep hole, that will show a water pump leak, which is likely what you have.
Yes my bad ha, its a 2005 Yukon with a v8 5.3 in it. lovely motor. This morning, i found the leak!!! i confirmed the leak is coming from the upper right most area of the pump on the bottom end of the seal. Looks like gasket failure. i will be replacing the pump, thermostat, belt and resivoir cap just to get all that out of the way! I will post pic of the leak its on my phone
strutaeng
Full Access Member
I would go ahead and just replace it. I spent like an entire weekend trying to fix a leak on my 06 Suburban. I thought it was the water pump gasket, thinking those were leaking. It turned out it was the pump and the leak was underneath the pulley so it was hard to spot it. That was like 5-6 years ago by now.
Good opportunity to inspect the mounting bolts because with mileage and age they start to rust. And go ahead and remove all the coolant and put fresh Dexcool.
Good opportunity to inspect the mounting bolts because with mileage and age they start to rust. And go ahead and remove all the coolant and put fresh Dexcool.
If you empty the entire system, should need about 3 gallons. Give or take. But would need to empty the engine.
strutaeng
Full Access Member
Yup, just buy another gallon of concentrated coolant for the mixture and you should be good.
When you get the truck running again, leave the overflow reservoir cap off. Go inside and turn on the heater full blast and flip the throttle a few times. You'll see air come out of the reservoir tank. The engine basically is self purging of air that gets inside whe you remove the water pump, etc.
Meanwhile look around and make sure you don't have leaks until reaching operating temperature.
Remember that the water pump bolts have a tightening torque specification when mounting it.
When you get the truck running again, leave the overflow reservoir cap off. Go inside and turn on the heater full blast and flip the throttle a few times. You'll see air come out of the reservoir tank. The engine basically is self purging of air that gets inside whe you remove the water pump, etc.
Meanwhile look around and make sure you don't have leaks until reaching operating temperature.
Remember that the water pump bolts have a tightening torque specification when mounting it.
No need to run the HVAC fan full blast. Just put it on max heat (temp). Blower use is optional; it does nothing for the circulation through the heater core.
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Has it been sitting for a while? I know sometimes gaskets will deform so to speak. Then a couple of heat cycles it'll swell back up and stop leaking. Just from experience.
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Man that's cool u found it. Sometimes u can bump the bolts a little and it'll stop. But aways good to replace.
no this truck is used religiously in my family. Mom always took it to mexico and we always used it on trips through the states. i have 384k miles on it and mom decided she didnt like me driving the nissan and traded the truck to me for the nissan. when i got it i had to replace the oil pickup tube o ring. all that is good too i checked so many time after repair for leaks. My dad also used it as a daily drive to and from work. Lots of well documented history as my mom made dad write down everything done to the truck in a journal and she has asked me to do the same.
384k miles sorry very dumb typo
how do you empty the entire system? as well as the engine?
Plugs on the engine that can remove for draining. Besides freeze plugs. If they still have them anyway.
ScottyBoy
Full Access Member
If you dilute your own concentrate, make SURE that you pre-dilute it in a seperate container with at LEAST a 60/40 dilution rate. I would actually recommend 50/50. didn't properly dilute mine and my water pump gaskets started leaking less than a year later. I had several mechanics tell me that too strong of a coolant dilution ratio can cause premature gasket failure. I read the same thing on several automotive forums online. Instead of just replacing the gaskets, I ended up just replacing the water pump again. It was under warranty, so I just swapped it out with no issue. Did the strong coolant REALLY cause my gaskets to fail?
I can't truly say one way or the other, but I am still definitely ALWAYS pre-mixing my coolant in a separate container from now on just to be on the safe side.
I was thinking about that the other day. I am going to buy a little five galleon bucket to do the dilution
You can buy 50/50 pre mix coolant. Takes the guess work out of it. Plus, I am lazy.
How long since the coolant has been changed? If it's been a long time or you don't know, just flush the engine with fresh water and drain as much as you can. The system is open and it's a good time to do it.
Calculate how much full strength coolant to make a 50/50 or 60/40 (coolant to water ratio) for your system capacity. Then add enough full strength coolant first to make the correct ratio, and top off with fresh water. Adding pre-mixed coolant to an engine that already has water in it further dilutes it and you'll never get to the minimum 50% strength.
Calculate how much full strength coolant to make a 50/50 or 60/40 (coolant to water ratio) for your system capacity. Then add enough full strength coolant first to make the correct ratio, and top off with fresh water. Adding pre-mixed coolant to an engine that already has water in it further dilutes it and you'll never get to the minimum 50% strength.
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