Coolant Reservoir: Level Going Down Slow - Corolland: the Toyota Corolla Forums

The level in my coolant reservoir keeps going down but it is very slow.

About 2 years ago at 77,000 miles I took car to my old mechanic to have checked because coolant reservoir was going down slow. He pressure tested the system and said radiator leaking where metal and plastic meet. The end caps were leaking. So supposedly he changed the radiator. May be he did not change it.

Now 2 years later at 95,000 miles the level in the coolant reservoir is doing same thing. Going down slow.

QUESTIONS: mechanic was supposed to take original factory radiator out because of leak.

Is there a way to tell if factory radiator is still in car and he never changed it.

What would be my plan of action: have system pressure tested. Check hoses. Check water pump.

Also if the radiator is leaking can you see it or must be pressure tested.

The first time I supposedly had a leak at end caps and got new radiator if they honestly changed it I never saw coolant on ground. The level kept going low real slow.

Now same thing. Nothing on ground but level is going low real slow again.

Any help would be great.

Thanks Frank.

Since it is a slow leak, pressure testing is the only way to see if it is leaking or not. Doubt that the leak, if it is externally leaking, will show up on the ground. Even that pink, crusty residue that sometimes forms around a water pump, is not always a sign of a leaking pump or leak source. If it is leaking internally, used oil analysis will let you know right away.

If the mechanic actually changed the radiator or not - impossible to tell now, unless he replaced it with an obvious aftermarket unit (won't say Denso or Toyota on it anywhere). More than likely, if it was leaking at the endcap, he probably just replaced the gasket between the aluminum core and the plastic tank.

Another possibility is that you are loosing coolant from the reservoir itself - system is perfectly fine. If your climate has a lot of temperature swings, could also be loosing coolant to the act of evaporation. System draws in coolant when needed when the system is cool, expels excess coolant when hot - coolant doesn't always makes it way to the recovery tank, some might have gotten lost in route (leaking hoses, past the radiator cap, etc.

Look for obvious signs of coolant loss, note any sweet odor inside or outside the cabin. Fill the reservoir to a mark, monitor the levels very closely. If you haven't already done so, get a UOA to verify that coolant is not getting into the oil. Get the system pressure tested at your earliest convenience. Can't do much until these are done - we'd be guessing at possible issues at this point. The UOA and pressure test should be pretty definitive at pointing out if and where you are loosing coolant.

Fish

Even if nothing is wrong I wanted to know what to check.

I thought I could check and tell if he took out factory radiator and put in different radiator. Where would factory radiator say say denso or toyota on it if I wanted to check.

Fish I do not know what my old mechanic changed if anything but bill charge 410.00 for radiator job.

Like is said level in coolant bottle is going down slow.

I am changing TURBO POWER COOLANT to TOYOTA RED this weekend.

I will set level to full in bottle and monitor it.

Fish maybe my radiators keep having leaks because of the TURBO POWER coolant my old mechanic used.

He did a coolant flush at 60k and got rid of toyota pink coolant and put in Turbo Power. Then at 77k he pressure tested system due to coolant level going low in bottle and nothing on ground.

He said end cap leak. 410.00 for supposedly radiator. He used Turbo Power coolant with new radiator. Now same thing is happening. Level going down slowly.

Do you think radiator problems are because coolant he used not good for radiator.

Just my opinion.

Thanks Frank

Should be on the top of the plastic tank - should be stamped with ink saying Toyota or Denso.

If he did it all for $200 - then I doubt he replaced it with a Toyota/OEM radiator - those run about $360 list price + labor. I don't think he could have gotten it at a discounted price, some have gotten OEM ones for as cheap as $170 or even under $100 online. He likely just popped the crimp on the end cap and resealed it. That will work, but eventually will leak again.

Cheap aftermarket radiators are in that price range - he also could have gotten a used OEM one, cleaned it up, installed that one. Another possibility - the core was leaking, and he just replaced the core - reused the end caps. You'll have to ask the mechanic to be sure - he should be able to look at the worksheet and tell you if it was changed or repaired. If it was OEM - he should have listed the part number on it.

Doesn't mean that all aftermarket ones are bad - Koyo is a big aftermarket and they make a pretty decent high performance aftermarket. Popular with the off-roading crowd, as it is a lot stronger than the OEM radiator - doesn't pop the cooler lines like the OEM ones when you go off-roading. But like they say, your mileage may vary. Some love aftermarket, some say stay OEM.

If it is leaking because of the Turbo Power Coolant - that is extremely hard to say for certain. If it is actually leaking at the radiator - I would chalk that up to be more of a poor repair or cheap aftermarket part, instead of a coolant compatibility issue.

Fish

He charged 377.00 PARTS AND LABOR FOR RADIATOR and 30.00 for TURBO POWER COOLANT.

Just asking a question. When you open the hood of my Corolla you look down and see the radiator. Right behind it you see a long plastic piece. This is the fan. On the end of the plastic on the passenger side of car in black on the plastic is written Toyota and Denso with some numbers.

Fish is this where it would be stamped if radiator was factory radiator.

THANKS FRANK

Not 100% sure I'm following what you are doing. You don't want to look at the fan shroud - that part is separate. You want to look on the plastic tank itself. Locate the fill cap, on that side of the tank, there should be a section where they stamp a part number, says Denso or Toyota or both.

Like I mentioned, possible he just popped the side off and replaced the gasket, that is a fair amount of labor to do that. I don't know for sure what your mechanic did - I don't know your mechanic, I can't see your car. So you could be just spinning your wheels here.

Need to verify the coolant level is dropping on the reservoir tank, do a UOA to check for internal loss of coolant, do a pressure test to check for leaks in the system.

Fish

It does say Toyota and Denso with a number on the plastic so their is a possibility he did not change radiator at all and I payed for a new radiator I just can't prove it. I do not use this mechanic anymore.

All I was saying was that on the passenger side of radiator some where in the area of the end caps. Their is a piece of plastic that has black writing on it. It says Toyota and Denso with a number.

Questions: where are factory radiators stamped toyota

If you take off end caps and put new gasket in will it leak again.

He charged 377.00 parts and labor to put new radiator in plus 30.00 for coolant

Would it cost that much to just put gasket in.

Thanks for answering my questions

Frank

I don't know off-hand exactly where they stamp them on those radiators - only that they will be on the plastic end caps on the side.

Not sure if he just repaired the radiator or replaced it - it would be on the worksheet, or that mechanic will know. The amount of labor to pull the end caps on, replace the seal, and reattach those end caps is pretty is extensive, even with the right tools. So that charge could be legit - just for parts and labor. Again, not sure, I don't that guy and I can't see your car - we're just spitballing at this point.

Also possible he might have sent it out to another shop to pressure test it, do work he couldn't do - as can't really do a good job without a large enough tank to completely submerge the tank - usually, you only see those at HVAC shops. Again - not sure if this was he did. Repairs like this tend to leak again - as there is some cause, initially, that cause the leak in the first place.

This point - no sense worrying about it - it is already done. Monitor coolant level, get a UOA, get the cooling system looked at by a pro.

Fish

What are END CAPS: where metal meets plastic on radiator or something else.

Thanks again for help. I am going to do coolant flush and change out TURBO POWER coolant and put in TOYOTA RED. I will fill reservoir up to fill line and monitor level.

Fish it is quite possible that there is no problem with my radiator and coolant system like you said.

The level in reservoir going down almost to bottom of reservoir is very slow and it could be from just hot and cold weather like you said.

Thanks

Frank