Re: Before you take anything apart

I have a 2001S 6speed. I did a 2 hour drive to see my mother. The temp was
approx 80 outside and when I got there I parked the car on the drive way. I came
out about 1/2hr later and noticed a wet spot in front of the driver's side front tire.
It was approx a couple of dozen drops. I could smell it was coolant and also felt
it with my finger. I checked later and it had stopped dripping and the wet spot
had evaporated. I check the coolant level and it looked OK and I drove the car
home (2hrs) in 90 degree weather watching the temp gauge the whole way. There
weren't any problems and when I got home I checked the coolant level and it still
looked OK. Also, didn't notice any drips when I got home. I'm guessing it's a small
leak and only when the system is pressurized.

Does anyone have any suggestions as to what it could be before I start disassembling
the front end to see what is leaking? I'm guessing I need to pull the front bumper cover,
wheel wells to get in there and see. I have the shop manual (15 binders) but doesn't
show the front radiators. Also I've looked at the pdf file that has the part numbers and pics.
Anyone have some good pics showing the driver's side radiator and hoses?

i would suspect either a) a hose connection at the radiator, b) a crack at a weld/connection, or c) leaves caused corrosion and a leak.

Nothing i know of that's chronic

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

I would remove the front bumper skin, then the driver’s side radiator shroud and finally move the A/C condenser away from the radiator.
If there is a leak you will see the wet spot immediately.

Pedro Bonilla
1998 Boxster 986 - 311,000+ miles: [www.PedrosGarage.com]
PCA National Club Racing Scrutineer - PCA National HPDE Instructor - PCA Technical Committee (Boxster/Cayman)

---

Racecar spelled backwards is Racecar

"Racing is life. Anything before or after is just waiting" ... Steve McQueen as Michael Delaney in "LeMans"

"If you wait, all that happens is that you get older"... Mario Andretti

"Being second is to be the first of the ones who lose" ... Ayrton Senna

My street car (04 base) started dripping around the water pump bearing a couple of days back. Took the cover off the firewall and it was fairly clear...plus a bit noisy.

G

Grant

gee-lenahan-at-gee-mail-dot-com

Make sure it''s not condensation from the A/C, which is normal.

I didn't have the AC on at any time, so I don't think it is that. I did
think of that already, but the fluid smelled like coolant. I'll be pulling
the front bumper cover as soon as it cools off some. Expected 105F
for the next couple of days.

I am expecting it to be a small leak when the system is pressurized.
I was trying to come up with a way to pressurize the system without starting
and running the car to get it hot. I do have a power bleeder that would be
perfect for doing this, but the caps are different between the brake master
cylinder and the coolant reservoir. I did pull out my old coolant cap when everyone
said to replace it to get rid of coolant condensation around the fill area. The
cap has something like a pressure release mechanism under the cap, so
I cannot drill a hole in the top and put a fixture to attach the power bleeder to,
even if you pull the mechanism out. If you look at the cap you will see what
I'm talking about. Any ideas on what cap I could get that would seal the opening
so I could drill a hole in the top to attach my power bleeder. If I'm successful
in finding a cap that would work, what pressure should I apply to the system
to look for a leak? What would be a ballpark pressure that the system runs
at when hot?

Quote
Larry Nakamura
I didn't have the AC on at any time, so I don't think it is that. I did
think of that already, but the fluid smelled like coolant. I'll be pulling
the front bumper cover as soon as it cools off some. Expected 105F
for the next couple of days.

I am expecting it to be a small leak when the system is pressurized.
I was trying to come up with a way to pressurize the system without starting
and running the car to get it hot. I do have a power bleeder that would be
perfect for doing this, but the caps are different between the brake master
cylinder and the coolant reservoir. I did pull out my old coolant cap when everyone
said to replace it to get rid of coolant condensation around the fill area. The
cap has something like a pressure release mechanism under the cap, so
I cannot drill a hole in the top and put a fixture to attach the power bleeder to,
even if you pull the mechanism out. If you look at the cap you will see what
I'm talking about. Any ideas on what cap I could get that would seal the opening
so I could drill a hole in the top to attach my power bleeder. If I'm successful
in finding a cap that would work, what pressure should I apply to the system
to look for a leak? What would be a ballpark pressure that the system runs
at when hot?

Best way to confirm the leak -- there's a leak if the fluid was coolant -- and to locate it is to pressurize the system hot.

Top up the coolant tank with distilled water. Do no overfill but bring the level up to something in the acceptable range.

Start the engine and with the A/C off drive the car around town in stop and go traffic with idling and mild acceleration up to speed (even if it is only 35mph or less) following by a stop, idling. Repeat.

When you hear the radiator fans come on the coolant is probably up to 212F.

Head home. On the driveway raise RPMs to over 1K and hold until you hear or a helper hears and tells you the radiator fans are on.

Shut off the engine.

Wait.

As the heat soaks into the coolant from the engine this raises the coolant temperature and pressure. If there is a leak, and there is, it will leak under these conditions -- the same conditions it leaked under before -- and you will know where the leak is coming from.

Frankly I don't think you need to go to trouble. If you are sure the fluid was coolant the passenger front radiator is leaking. My Boxster radiators never leaked but all 3 of my Turbo radiators leaked and it was through the seam where the bottom tank connected to the radiator.

I say radiator because it is rare a hose is leaking. But when you expose the radiator (after taking off the front bumper cover) if you see coolant leak sign from a hose/fitting area you can try tightening the hose provided the hose appears to be in good condition. Squeeze the hose with your finger tips pressing the bottom side of the hose. If the hose feels soft -- in severe cases a tech an push his finger tips through a bad hose -- it is bad. In 16 years, 317K miles I never had to replace a hose in my Boxster. The techs told me the hoses just last but it helps to change the coolant every 4 years or so and regular use also helps maximize the life of radiator hoses.

If you replace the driver side radiator it might be worth the time/trouble/money to proactively replace the passenger side radiator, too. Same miles. Same exposure. You can inspect the passenger side radiator and if you see any sign of coolant residue that's a leak albeit probably small. But a small leak is in some cases worse than a large one in that at least with a large leak one doesn't continue to drive the car. Drive the car with a small leak and system will not remain pressurized and under some conditions this can allow coolant to flash to steam in the hottest parts of the engine and this steams blocks coolant flow and can lead to localized overheating which can result in collateral damage to the engine.

I only have 58K miles on the car. It's been garaged for 100% of it's life.
I've had the front radiator grills on the car for 15 years or so. If I recall, the
ones mad by Eric the plug guy. They work great in keeping debris out of the
radiator area. So much so, that I haven't ever found enough stuff to vacum
out. Maybe some small amount of small gravel.

Anyway, I'm not sure running the car to pressurize the system will work.
Remember I said I drove the car home 2hr in 90+ weather, and the coolant
level didn't drop at all and there was no leaking in front of the driver's side
tire when I got home.

That's why I was trying to come up with a way to pressurize the system
using my power bleeder. I just need a cap that fits the coolant reservoir opening
and drill a hole in it to add fixture to attach my bleeder to. If I took it to the dealer,
this is what they would do to look for a leak.

Also, I'm not sure I want to drive the car around with the bumper cover off. I mean
I would do it if I need to. My thoughts are a leak only does one of two things. Stays the
same or gets worst. It never gets better on it's own. The heat wave is still going on
here in the north bay, so it will be a few days before I start pulling stuff apart.

Quote
Larry Nakamura
I only have 58K miles on the car. It's been garaged for 100% of it's life.
I've had the front radiator grills on the car for 15 years or so. If I recall, the
ones mad by Eric the plug guy. They work great in keeping debris out of the
radiator area. So much so, that I haven't ever found enough stuff to vacum
out. Maybe some small amount of small gravel.

Anyway, I'm not sure running the car to pressurize the system will work.
Remember I said I drove the car home 2hr in 90+ weather, and the coolant
level didn't drop at all and there was no leaking in front of the driver's side
tire when I got home.

That's why I was trying to come up with a way to pressurize the system
using my power bleeder. I just need a cap that fits the coolant reservoir opening
and drill a hole in it to add fixture to attach my bleeder to. If I took it to the dealer,
this is what they would do to look for a leak.

Also, I'm not sure I want to drive the car around with the bumper cover off. I mean
I would do it if I need to. My thoughts are a leak only does one of two things. Stays the
same or gets worst. It never gets better on it's own. The heat wave is still going on
here in the north bay, so it will be a few days before I start pulling stuff apart.

If you have removed the bumper cover and unbolted the A/C condenser and gently swung it out of the way and found only a bit of gravel that's good. That means the radiator and condenser have (probably) not suffered any from corrosion as would be the case as most cars accumulate quite a collection of mostly plant trash/litter which packs in around the bottom of both the condenser and radiator.

But that doesn't mean the radiator can't leak. I kept the radiator ducts of my Turbo clean -- they were cleaned as part of the every 5K mile oil/filter service -- yet all 3 radiators developed leaks and had to be replaced. The problem is the heat up and cool down cycles and the expansion and shrinkage that goes with this over time cause the joint/seal of the bottom of the radiator and the radiator core to fail over time. There is another contributing factor and that is the variability of the radiators. My Boxster radiators never leaked in 317K miles and this despite the fact with the Boxster the coolant temperature swings were greater than with the Turbo. Turbo radiators manifested leaks at 130K miles.

Oh running the engine -- with the A/C off -- to the point it is fully up to temperature and then running it some more until the coolant temperature climbs to where the radiator fans are switched on (212F by my observation) then shutting off the engine will pressurize the cooling system and in a way a regular pressure test can't.

The system is pressurized hot. In my experience a bad coolant tank that was mostly leak free -- except as it turned out in the rare cases where I did shut off the engine that was hot enough to have the radiator fans running at the time I shut off the engine -- when I purposely got the engine hot and with the fans running then shut off the engine gushed enough coolant out of the a split (the mold seam than runs along the bottom of the tank) to nearly empty the tank. Yet when left overnight to cool and the next morning after adding nearly a gallon of distilled water to the tank was leak free and remained leak free during the drive to the local Porsche dealer.

(In another case with another car a radiator pin hole leak only appeared those times I shut off the engine with the engine coolant hot and the system pressure increased from the engine heat soak. The tech found the leak fortunately helped by the fact the pinhole was on the back side of the radiator and up high so it was visible and it was the anti-freeze residue stain that caught the tech's eye.)

Driving your car even in warm weather won't get the coolant as hot as it can be in the procedure I described because 1) Often the A/C is in use and the radiator fans run all the time which moderates the coolant temperature and cooling system pressure; or even if the A/C is not being used as the coolant temperature rises and the fans come on *and the engine is allowed to continue to run* they will promptly lower the coolant temperature which lowers the coolant pressure and the system never sees very much pressure.

If there is any coolant leakage it will be small and because everything is hot the water will evaporate and there will be no sign of wetness. Just a white residue that is the solids from the anti-freeze will be present. This is as damning as liquid coolant though, or should be.

I never suggested you drive the car around with the bumper cover off. If you feel you must see the radiators totally exposed you remove the bumper cover at your house, in your garage. If you want to view the radiators and hoses/etc hot you drive the car before hand to get everything nice and hot, to the point the radiator fans are running. Then shut off the engine and proceed to remove the bumper cover and expose the radiators. Then you can start the engine and fast idle it until the radiator fans come on then shut off the engine and let the heat soak raise the coolant temperature and pressure. Then you will see liquid coolant.

Or you drive the car around and get the system hot then fast idle the engine to the point the radiator fans come on then shut off the engine. Wait. Then after awhile when you see coolant then you can remove the bumper cover and look for the source of the liquid coolant.

But as I said before there's a leak. That you spotted coolant is proof enough of that. It is just a question of where the leak is. Radiator? Or a hose? Or where a hose fits to the radiator? Thus there is no need to pressurize the system cold or hot. Almost certainly just removing the bumper cover and gently swinging the condensers out of the way and looking for anti-freeze residue and you will know where the leak is.

I must stress you should not continue to use the car as you normally would but get this leak fixed and for the reasons I covered in my first post.

Buy Pittsburgh radiator pressure test kit 63862 or use loner kit from Autozone for cap fit.
I don't know the pressure.

fit the coolant reservoir threads on my '00 S.

So I finally got around to looking at this issue. This is after the weather cooled some and
the smoke from the nearby fires finally cleared some. This was the Mendocino Complex fires
in CA. I live in Clearlake.

Anyway, I took off the 2 wheel wells and started to get ready to take off the front bumper
cover. I did tighten any hose clamps I could get to at this point. I then got the loaner kit from
Auto Zone to pressurize the system. First, I tried pressurizing the system for 4-5 hours and
did not see any leaks. Then I started the car (100 outside temp) and let it run for a while so
it would come up to temp and the fans kick on. Then I turned the car off and pressurized the
system again for a while and still did not see any leaks. So at this point I guessing it was
a clamp thing and didn't go any further. I also could not see any signs of residue.

I didn't take the bumper cover off as I didn't see any need to and also I probably would
need a second hand taking if off and putting it back on. Also, the only clamp I couldn't get
to was the one at the top of the radiator, and everything looked nice and clean.

I will keep a close eye on the coolant level to make sure I don't have any further issues.
Oh, I wish they would have made it easier to see the coolant level on the indicator in the
trunk. Maybe if it was clear not like smoked glass. Also, I do carry a spare quart of coolant
in the trunk.