lilsettals
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Have a problem with my 04 Yukon every time I fill in my coolant reservoir it feels uneven, despite having a new water pump, hoses, clamps, and I also lose coolant under load.
Coolant reservoir uneven
- Thread starter lilsettals
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A few questions, how quickly are you losing coolant? Do you have rear air? A non-visual leak can come from the waterpump weephole (which is new), a leak at rear of vehicle (if rear air), is your passenger footwell damp, or possibly a head issue (porous, cracked, or gasket). How does your oil look, and can you run a compression check? Others with more direct experience will chime in.
mikez71
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Don't forget the radiator. A leak at the endtank seams can sometimes be difficult to spot.
Absolutely @mikez71, I missed that
Marky Dissod
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I say this because I used to own 3 Caprice 9C1-LT1s & a Fleetwood; once I learned to accept this as a fact of life, my cooling system worked well.
Burp it again.
Burp it again.
lilsettals
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So I had my mechanic do a compression test and it held. My oil is clean and I did a combustion test and no exhaust fuel in the coolant system. I did a dye test and I did find the clamps at the end of the hoses to be not holding good so I replaced them. But I am still losing coolant and the reservoir is not filling evenly.
lilsettals
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Yes I have rear air and it works and no I dont have a heater core leak. It happens to drop below the fill line every 2 weeks or so. I drive it every day.
Marky Dissod
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Put some dye in it. Check it again in 2 weeks after you burp it again.
If you've rear HVAC, don't forget the right rear wheel well area, there's another heatercore there, and it's just one of the possible leakers.
If you've rear HVAC, don't forget the right rear wheel well area, there's another heatercore there, and it's just one of the possible leakers.
mikez71
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How far does it drop in 2 weeks?
And what do you mean by 'not filling evenly' ?
And what do you mean by 'not filling evenly' ?
@Marky Dissod makes a great point. I have an Audi and it is mandatory to use a vacuum-based coolant fill system. It has been great, you can perform a vacuum test on the system (~30mins), if it holds you've confirmed system is tight, and then flip the valve and it fills with no air in the system. Auto-burp.
lilsettals
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I did no leaks anymore after clamps were changed
lilsettals
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Like the fill funnel area where you pour the coolant into the overflow tank is higher than the rest of the space in the tank.
Marky Dissod
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Can it really hurt to burp it again? Pretend to the rest of us you burped all the air out the first time.
It doesn't fill evenly because the reservoir floor has baffles meant to slow your pouring of coolant from getting into the rest of the system all at once.
It doesn't fill evenly because the reservoir floor has baffles meant to slow your pouring of coolant from getting into the rest of the system all at once.
Yes, the part of the tank that has the cap is molded higher than the rest of the tank. Normal. Look online for pics.
Check and fill the level when it's cold; checking it right after a drive should show it to be higher than when cold. Your surge tank likely has a mark (with an arrow pointing to it) to show how high to fill it when cold; on my '04 that level is the seam at the middle of the tank. As long as you fill to that point, the level in the rest of the tank doesn't matter. Use it as a reference to determine how much coolant is leaking, but always check it at the same engine coolant temperature, preferably when cold.
You mentioned a compression test; was that for the cylinders? If so, pressure test the cooling system and monitor the leakdown, if there is any.
Check and fill the level when it's cold; checking it right after a drive should show it to be higher than when cold. Your surge tank likely has a mark (with an arrow pointing to it) to show how high to fill it when cold; on my '04 that level is the seam at the middle of the tank. As long as you fill to that point, the level in the rest of the tank doesn't matter. Use it as a reference to determine how much coolant is leaking, but always check it at the same engine coolant temperature, preferably when cold.
You mentioned a compression test; was that for the cylinders? If so, pressure test the cooling system and monitor the leakdown, if there is any.
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mikez71
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Might also check or replace the reservoir cap..
I just noticed today my '05 uses corrugated loom to drain any overflow..
If your cap was weak, steam might settle in that line and you might not notice any discharge...
I just noticed today my '05 uses corrugated loom to drain any overflow..
If your cap was weak, steam might settle in that line and you might not notice any discharge...
Actifenpleinair
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I noticed nee reservoirs themselves are quite affordable, 50 -100 bucks if I recall on RockAuto. The old ones discolor, and you'll be able to see the orange fluid way easier in a new reservoir. May be a Crack in the reservoir, or even in the valley cover crossover tube front of v8.
mikez71
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I just got a reservoir with cap from ebay, $36.64 shipped. ($34 plus tax)
Although apparently the cap was bad. (holds vacuum)
Although apparently the cap was bad. (holds vacuum)
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Ken Casher
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I replace radiators at 200K miles. I finally figured that out after having to nurse my 2001 Taho back home because of a end tank leak. Like you I knew there was a leak on the Tahoe but I couldn't see it until it got bad enough to cause problems. I have a 98 subie outback that blew the radiator less than 10K miles after I changed head gaskets. It's now waiting for me to change them again.
