Help Finding a Coolant Leak - Pics

[gsbarry]

'06 V

I've got a coolant leak that I'm having trouble tracking down. It only leaks noticeably while the car cools in the garage over several hours, though I haven't been able to see it leak myself - just the small 3"-6" puddle it leaves. It does not appear to leak while the car is running - cold or hot. The puddle is under the front left corner, directly under the left side of the rad. At the moment I suspect a minor crack in the rad, though my reading of other posts indicates the V rad was a higher quality part. I attempted to pressure test through the reservoir cap, but the system did not seem to hold any pressure at all . I did notice the coolant level dropped slightly while trying to pressure the reservoir, indicating an air pocket was being filled somewhat, though i could not see any further leakage. My second guess is the upper rad hose has a minor leak, possibly from a weak clamp. The water pump and surrounding area appears dry.

I've got some pictures showing the residue pattern on the left side of the rad and parts nearby.

Here you can see a small amount of residue on the front of the rad side tank, a small pool on the frame rail, and further leakage down the side of the tank. The upper hose itself appears clean.


Here is a better angle of the spray on the front of the rad.


More of the front of the rad. You can see the label shows a date of 5/1/06 - not sure if there might have been a part update mid-year.


The drip path for most of the coolant seem to collect at the generator cooling hose connection at the rad. You can just barely see this hose from the top side - just left of the green striped cable conduit, above the frame rail in this picture.


You can more clearly see the drip path to the generator cooling hose from the bottom here.


What do you guys think? Should I bite the bullet and replace the rad on a hunch ($220 OEM part)? It looks like the A/C condenser needs to be removed to do this. Does anyone have any other ideas to confirm a diagnosis? It was very surprising/strange to me that I could not sustain any pressure and see no further leakage while pressure testing. Has anyone seem this kind of spray pattern before?

Given that this appears to be a slow leak, I don't think we have a case of coolant spraying out every which way under pressure, meaning the highest location of residue would likely be the culprit, which seems to be in the vicinity of top front left corner of the rad side tank.

Thanks for any input,

Greg

 

[xlrlist01]

'06 V

I've got a coolant leak that I'm having trouble tracking down. It only leaks noticeably while the car cools in the garage over several hours, though I haven't been able to see it leak myself - just the small 3"-6" puddle it leaves. It does not appear to leak while the car is running - cold or hot. The puddle is under the front left corner, directly under the left side of the rad. At the moment I suspect a minor crack in the rad, though my reading of other posts indicates the V rad was a higher quality part. I attempted to pressure test through the reservoir cap, but the system did not seem to hold any pressure at all . I did notice the coolant level dropped slightly while trying to pressure the reservoir, indicating an air pocket was being filled somewhat, though i could not see any further leakage. My second guess is the upper rad hose has a minor leak, possibly from a weak clamp. The water pump and surrounding area appears dry.



Greg

If you are going to pull the rad, you could get it tested before you buy a new one.

Also, it is surely very rare for a leak to stop while moving and show up when switched off. It seems more likely that it is leaking but that the coolant is blown away. Failure to get any pressure at all during a pressure test suggests more than a very small leak, a small (very small that is) leak would enable some kind of pressure build up.

 

[gsbarry]

I agree that the pressure test result is very odd that it won't hold any pressure when combined with a slow leak. I'll recheck to ensure it's not a leaking tester.

It is very possible that this is just a very slow seep while running or not. I was inspecting the area with the car idling hot in the garage for a good 15 min and was unable to detect any additional drip/leakage. Needless to say, I am very reluctant to pull the rad and condenser w/o a confirmation.

 

[ald42]

Hi,could this be the typical rad leak where when it's hot things expand and no leaks and when things cool they shrink and the gap/defect opens up and leaks. AL

 

[buki]

Maybe I'm being too Simplistic.

I live in a climate similar to yours where humidity rules.

I have found wet spots in exactly the same place as you several times this season.

Consider this...the fact that you may have to remove the ac condenser to fix it may just mean that your ac unit is the source of what you think is a leak.

Rule that out before you spend a bunch of cash.

Have you had a 'low coolant' message on the DIC?

Just a suggestion

 

[klaptrapper]

Couple things occur to me. First, could your "leak" just be condensation from your air conditioner. A puddle shows up under the car in the left front, from such. Also, it could be that you can't pressurize the overflow tank because it has a overflow tube which will exhaust any air introduced at the cap.
Just saying............

Rusty 06 V

 

[gsbarry]

It's definitely a coolant leak, orange fluid - dex cool - dripping off rad.

condensation from the a/c drips on pass side further back under evap core.

I'm fairly certain the overflow tube flows coolant from the rad to the reservoir (due to thermal expansion), which is sealed, unless the pressure is high enough to open the relief valve on the reservoir cap at 18 psi, which is replaced by the tester in this case. Air can come up through the overflow tube if there is air trapped in the cooling system, but that's beside the point.

I'll check my tester again when I get a minute.

 

[klaptrapper]

You certainly have a knowledge of the problem and the system. I didn't realize that, when I posted my inadequate suggestions.
Good Luck

Rusty
06-V

It's definitely a coolant leak, orange fluid - dex cool - dripping off rad.

condensation from the a/c drips on pass side further back under evap core.

I'm fairly certain the overflow tube flows coolant from the rad to the reservoir (due to thermal expansion), which is sealed, unless the pressure is high enough to open the relief valve on the reservoir cap at 18 psi, which is replaced by the tester in this case. Air can come up through the overflow tube if there is air trapped in the cooling system, but that's beside the point.

I'll check my tester again when I get a minute.

 

[V Happy]

Help finding a coolant leak

Gsbarry
Finding coolant leaks is what I used to do for a living. What kind of pressure tester are you using? If u are taking off the pressure cap and pressurizing the upper cylinder you could be leaking out of the actual overflow tube. You need to pressurize from the lower cylinder at the bottom o ring cylinder of the cap. I'm assuming this is why you are not building up any pressure. You will not see a leak unless you have some pressure built up. The way those radiators are built they use a neoprene gasket between the radiator core and the radiator tank. The gasket is put on the core then torque clamp the tank on top of that. Then the aluminum tabs are bent over the tank lip to seal the radiator tank to the core. I have had plenty of those core gaskets start to leak after time. I'm sure if you get proper pressure on the system you will see your leak. From your pictures it will be a tank gasket,cracked tank or just a hose connection. From the stains I'm seeing it appears you need your system flushed and filled with new GM coolant. I just did mine last year. One thing on a V it has a special pump that pumps the fluid up to the super charger. That plate on top of the supercharger is a good place to bleed and fill the system. If you have a tech 2 you can run the pump with the tech 2.
V Happy

 

[gsbarry]

I think I need a bit more explanation

What kind of pressure tester are you using?
A threaded cap adapter connects to a conventional spring loaded cap tester with hand pump. I attached this to my compressor - regulated to 15 psi - due to the large volume of air in the reservoir (surge tank in the manual). Typically the rad cap is the location for a pressure test, but we have capless rads - I have confirmed the manual prescribed testing location is the surge tank cap. The adapter screws on to the surge tank in the same fashion as the cap itself. My tester appears to be the same as in the manual below.


If u are taking off the pressure cap and pressurizing the upper cylinder you could be leaking out of the actual overflow tube. You need to pressurize from the lower cylinder at the bottom o ring cylinder of the cap.
What do you mean by upper and lower cylinder? The "surge tank inlet hose", what most call the overflow tube, is the skinny hose at top right of the pic below, and is connected to the rad at the other end. I'm not sure where you are saying the air is escaping, or how I would prevent this. I'm just not following is all.


I have had plenty of those core gaskets start to leak after time. I'm sure if you get proper pressure on the system you will see your leak. From your pictures it will be a tank gasket,cracked tank or just a hose connection.
I suspect you are right , just want to eliminate the possibility of a simple hose connection. Don't want to R&I rad and condenser needlessly.

From the stains I'm seeing it appears you need your system flushed and filled with new GM coolant.
Why do you say this? The cooling system was flushed within the past 18 months/15k miles. Recall that GM coolant is orange from the bottle, this is not rust discoloration of green coolant.

One thing on a V it has a special pump that pumps the fluid up to the super charger. That plate on top of the supercharger is a good place to bleed and fill the system. If you have a tech 2 you can run the pump with the tech 2.
You are right about the fill plate and separate water pump for the supercharger. However, my reading of the manual and inspection of the system indicates that the supercharger (charge air) cooling system is a separate cooling circuit. It has it's own fill location (plate or hose terminal above accessory belt), rad (in front of condenser), and water pump (right frame rail - electric). Draining and filling the engine cooling system should be done at the rad drain and surge tank. Just wanted to clarify for others that may read this.

Greg

 

[V Happy]

Help finding a Coolant leak

Rusty
What I call the overflow tube is on your first picture showing your hand pump.(attachment 4632) It is the little 90 degree hose off of the cap female,part of the surge tank. What I think you are calling the over flow is a bleed tube to let the air in the block and cooling system enter the surge tank. Sorry if I'm not making this perfectly clear. I do not believe the supercharger pump and coolant is an independent system. That system is tied into the conventional cooling system. Being that system has to cool the supercharger that high above the surge tank is why they want you to run that pump with the tech 2 when filling the the cooling system.
V Happy

 

[gsbarry]

Diagnosis - More Questions

I had one of those moments when you slap your forehead , how did I not see this before?
My problem was a lack of understanding how the surge tank cap functions under high pressure. I know exactly what you mean now Vhappy by "upper and lower cylinder".
Here you can see the small hole on the interior lip of the cap hole (lower cylinder) and the plastic tube (more like cable conduit) that just hooks under the edge of the surge tank, connected to nothing. When there is a high pressure condition in the tank, the inner portion of the cap lifts slightly to expose this little inner passage.


My tester was fitting on the outside threads only.


Once I realized the air was shooting straight out the side, i used my finger to temporarily plug the real overflow tube.


I was able to achieve pressure in the system, this revealed a now obvious crack in the plastic side tank, which was barely discernible in my first post.


So the diagnosis is now clearly to replace the rad,

which also seems to require removal of the condenser. Thanks to Vhappy and Klaptrapper (whom I misunderstood on the overflow tube) for helping out!

I must say, all of my repairs (which should have been minor) have turned into big ordeals with this car. I am less than satisfied with the serviceability of this car.

So my next question is due to the statement in the service manual that:

"IMPORTANT: The condenser and receiver dehydrator are integrated and cannot be serviced separately."

Typically, anytime an A/C system is serviced the drier/dehydrator needs to be replaced due to water saturation. That said, does anyone know if it is necessary to replace the condenser anytime the system is open? (Turning my $280 problem into a $400 problem).

Another small issue I could use clarity on:
The manual indicates that transmission fluid also runs through the rad, but I cant find any further information on this procedure (I must have an incomplete version). The question is whether the tranny fluid needs to drained prior to disconnection of these lines - I would think it is high enough relative to the tranny to not be necessary. Also, is there a need to purge air from the transmission lines? Or just run and top off as necessary? Just want to check, everything is different on this car.

 

[klaptrapper]

My question is, how prevalent is this failure of our cooling systems? Any one else have this happen? If it is prevalent, I doubt GM has enough stocked NOS radiators!!!

 

[V Happy]

Greg
im sorry it is the radiator. I would also make sure the car is not over heating. That is generaly what will crack those plastic tanks. It may have happened if there was ever a low coolant condition or a stuck stat. Also I would be surprised if you have to pull the condenser to remove the radiator. That may be true with these cars but that is generally not the norm. The tranny lines will lose a little fluid out of the cooler but it shouldn't be much. I'm not quite clear weather u have a manual or not?
Good luck
V Happy

 

[gsbarry]

Thanks. I obtained an electronic service manual split into 50 or so files a while back. It seems to have 90% of the information I need, but is missing some sections.

The manual does call for removal of the condenser to remove the rad. As far as I can tell though, the only reasons to do so are the 4 mounting tabs where the condenser rests on the rad, and a small clearance issue on the right side with one of the A/C lines. You can see both here:


It seems like you might be able to persuade the condenser out of the way. But this also seems like a good way to cause a refrigerant leak, putting you back to servicing the A/C. I'm more inclined to persuade the condenser out of the way if it has to be replaced under the "correct" method. But if it's simply a recover, R&I, evacuate and refill operation, I'm inclined to use the "correct" method.

I have not experienced an overheat condition (though I am the third owner), at least not as far the temp gauge would indicate. I did replace the thermostat several months back because it stuck open on one occasion - meaning the engine did not heat up. Since then temp operation has been normal, in the 190 to 220 range depending on ambient and driving conditions.

I did notice that the crack is directly behind the upper coolant inlet hose. This would be the location that takes the full force of any hot fluid streaming into the rad - think fluid dynamics, of which I am no expert - this force could have stressed this portion of the rad over time. This is only speculation though.

 

[V Happy]

Help to find coolant leak

Greg
i replaced my stat about a year ago(stuck open). If you are in no big hurry I will look up R&R for the radiator in my oem manuals I will almost bet the condenser can stay in place. You will need a assistant to keep from damaging anything else. I know if you look back in the forum there was Change in the XLR radiator since they have been out. All I'm saying is be careful to get the right radiator I remember seeing some of the older ones on EBay. I may have time tonight to look up the r&r
V Happy

 

[V Happy]

Help find coolant leak

Greg
I did look up the R&R and u are correct they tell u to evacuate the condenser. I also looked up R&R on the condenser which they do not have you pull the rad. This leads me to believe you can move the condenser out of the way enough to R&R the rad. In any case I would remove the fan assembly which will give room to move rad and condenser ahead a bit to separate the two. Sorry I couldn't be more help. Let us know how you finally accomplish the task. If you do open the freon system you need to seal up the lines the best u can to keep moisture out. Even if you do open it up I wouldn't replace the condenser because the dryer is attached to it.
V Happy

 

[gsbarry]

Octopus Rad

I ordered a replacement rad today from RockAuto for $230 - AC Delco P/N 10346017. I had to go with the AC Delco unit because the aftermarket rads were missing two connections (for the P/S).

My V rad has 8 connections - that's not a typo. They are:
1) Main/Upper Coolant inlet
2) Main/Lower Coolant Outlet
3) Coolant bleed-off tube outlet
4) Generator coolant outlet
5) Transmission fluid inlet
6) Transmission fluid outlet
7) Power steering fluid inlet
8) Power steering fluid outlet

I was surprised by the P/S fluid being run through the rad, because these connections are not mentioned at all in the service manual procedure yet I see them clear as day (could be a LC3/LH2 difference that didn't get updated). jimkroeker (another forum member who has replaced the rad on his V) has confirmed this to be the case. I have also traced the lines as best I can - it's a maze of hoses with limited visibility at points - and I'm fairly certain I traced two of the connections to the steering system. There's a possibility it could be an engine oil connection, before moving through to the auxilary intercooler in front of the left wheel. We shall see once disconnected. The trans fluid is routed to an auxilary intercooler in front of the right wheel after it passes through the rad. Base (LH2) models may have a different plumbing setup, most likely the P/S connections and therefore the possibility of using aftermarket rads. YMMV

I'm going to try and nudge the condenser out of the way without disconnecting. We'll see how it goes. Rad should come in next week.

Greg

 

[klaptrapper]

"Generator coolant oulet" seems strange, no return to the coolant system and what is the function of the "generator"?

I ordered a replacement rad today from RockAuto for $230 - AC Delco P/N 10346017. I had to go with the AC Delco unit because the aftermarket rads were missing two connections (for the P/S).

My V rad has 8 connections - that's not a typo. They are:
1) Main/Upper Coolant inlet
2) Main/Lower Coolant Outlet
3) Coolant bleed-off tube outlet
4) Generator coolant outlet
5) Transmission fluid inlet
6) Transmission fluid outlet
7) Power steering fluid inlet
8) Power steering fluid outlet

I was surprised by the P/S fluid being run through the rad, but jimkroeker (another forum member who has replaced the rad on his V) has confirmed this to be the case. I have also traced the lines as best I can - it's a maze of hoses with limited visibility at points - and I'm fairly certain I traced two of the connections to the steering system. There's a possibility it could be an engine oil connection, before moving through to the auxilary intercooler in front of the left wheel. We shall see once disconnected. The trans fluid is routed to an auxilary intercooler in front of the right wheel after it passes through the rad. Base models may have a different plumbing setup.

I'm going to try and nudge the condenser out of the way without disconnecting. We'll see how it goes. Rad should come in next week.

Greg

 

[gsbarry]

The generator aka alternator return line is at the water pump. First time I've seen a water cooled alternator as well. To clarify, direction of flow is water pump, generator, then rad. Should be marked as inlet on rad, not outlet.