losing coolant, 2007 GL450
Jacked the GL up, found coolant dripping from dirver-side. The lower portion of driverside radiator is wet. and above that there are some dried coolant dusts as shown in photo.
haven't checked the water pump yet, might need to remove the fan assembly to check water pump area.
seems the radiator is leaking.
Is this a rare case? since there are not many posts on this topic in this forum.
Thanks,
driverside radiator, around the coolant drain plug
driverside radiator, possible dried coolant
Back and down. So look for leaks forward and up from where you see the water pooling.
There is a very long o-ring between the tanks and the fins module. I do not know how vulnerable that is. It is thin, but thoroughly clamped in place.
Kudos to you for seeking out the actual source of leakage. You might get better results by doing so while the cooling system is hot and pressurized, but needless to say that is physically more challenging.
From all accounts, the water pump is as long lived as the engine internals. I recall maybe one or two instances of its replacement. The water pump is located on the opposite side of the motor from the power steering heat exchanger.
once receiving it will try apply blue locktite to the power steering return nut threads.
Yes I tried to torque the nut, but it was hard to reach. will remove the fan assembly to have more clearance to tighten it, and also to check the water pump.
I was able to tighten the nut with just a small crescent wrench. You can get a set of stubby flex head wrenches for under $20 on Amazon.
On a 17 year old car I would not hesitate for 30 seconds to replace the radiator, good decision.
Luckily FCP euro has 90 day return policy. in case those parts are not needed.
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Counterpoint: If it ain't broke, don't fix it. Whenever you disrupt a stable equilibrium, there is risk of destabilizing other items. It is not a small job, and if coolant has been properly maintained, there is little reason to believe either aluminum or plastic have degraded. The o-rings, yes, but they are held in place.
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"Are you a 'throw away the apple;' or a 'cut out the bad part' person?" Neither way is "wrong" or "right" and both have their benefits and drawbacks.
It would be good to have the spare radiator on hand in case you break the o-ring tightening the power steering thingy nut.
The other thing that makes me hold off from non urgent repairs: Suppose I do the repair, and then wreck the car on the test drive afterward.
If I owned one of these, and there was a problem like a leaking something-or-other, I would replace the leaking part and be willing and ready to replace other parts if needed. Collateral damage or domino-effect maintenance.
If committed to long term ownership on these things, expense cannot be spared. Otherwise the maintenance and repair snowball accelerates downhill and these cars start eating wallets exponentially.
If I owned one of these, and there was a problem like a leaking something-or-other, I would replace the leaking part and be willing and ready to replace other parts if needed. Collateral damage or domino-effect maintenance.
If committed to long term ownership on these things, expense cannot be spared. Otherwise the maintenance and repair snowball accelerates downhill and these cars start eating wallets exponentially.
If it were an aircraft, the whole engine would be rebuilt on a schedule designed to eliminate virtually all in-flight failures. But this is not an aircraft. Component failure leads to you pulling off to the side of the road and calling AAA, not desperately hoping for a safe place to land.
If I could re-do my radiator replacement, I first would have been more diligent about finding the source of the leaks (it turned out it was power steering fluid and coolant leaking from a lower radiator hose). If I went ahead with the radiator replacement, I would have changed the power steering pump and reservoir, and low pressure hoses, and the upper and lower radiator hoses, and lower heater hose while I was in there.
There are two risks in doing any work. One is disrupting a stable situation; for example, if you change the thermostat, you may find the upper radiator hose o-ring cannot be reused. It was sealing fine; now it does not anymore. The other is installing imperfect parts; I removed a probably good radiator and replaced with one on which the drain petcock promptly failed and the inlet pipe had to be polished to make a good seal. A friend of mine laboriously installed a fuel pump only to find out much later that the one he installed was bad. It is no longer a world in which parts quality can be relied upon.
If you are willing to have a risky vehicle, change parts on an as-needed basis. This is cheaper but costs you in gray hairs. If you want as-new aircraft level reliability, do complete rebuilds of subunits, but understand this will be expensive (cost you will not recover if a rock falls from the sky) and still may cost you gray hairs.
Data points on the maintenance spectrum:
- deferred maintenance --> not recommended
- fix only what's broke --> seems to be eric_in_sd's preference?
- preemptive maintenance --> this is my preference - fix what might be broke or could become broke, plus anything else in the neighborhood
- 10-year rebuild --> S-Prihadi example
- aircraft maintenance
If I owned one of these, and there was a problem like a leaking something-or-other, I would replace the leaking part and be willing and ready to replace other parts if needed. Collateral damage or domino-effect maintenance.
If committed to long term ownership on these things, expense cannot be spared. Otherwise the maintenance and repair snowball accelerates downhill and these cars start eating wallets exponentially.
If I owned one of these, and there was a problem like a leaking something-or-other, I would replace the leaking part and be willing and ready to replace other parts if needed. Collateral damage or domino-effect maintenance.
If committed to long term ownership on these things, expense cannot be spared. Otherwise the maintenance and repair snowball accelerates downhill and these cars start eating wallets exponentially.
And then systems that have the potential of prematurely ending the power plants life, such as cooling and lubrication, yes, sure fix that if it’s about to be broken - but only to the bare minimum necessary of ensuring continued operation.
It’s still just a $5000 car no matter how many parts you throw at it.
And then systems that have the potential of prematurely ending the power plants life, such as cooling and lubrication, yes, sure fix that if it’s about to be broken - but only to the bare minimum necessary of ensuring continued operation.
It’s still just a $5000 car no matter how many parts you throw at it.
I just spent some time troubleshooting the secondary air pump. It turned out to be a disconnected vacuum hose on one of the valves. Aargh. Useless! All because the Los Angeles basin traps air.
If you enjoy your vehicle and like what it offers, the real question is $6000 versus $30000 - $65000 for a newer/new one to replace it.
Sure, you could replace it with another one of a similar age for $5000 (though not where I live), but the odds are pretty good you'll still be facing material repair bills in short order.
If driving what you have is still enjoyable it's probably worth the repair. But if you begin to look at it with distrust or distain, then that $5000 value becomes a whole lot more relevant.











