Losing a bit of Anti-Freeze - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Rob175 · 02-21-2018, 09:21 AM

I own a 98 Boxster with 79,000 miles. I ONLY drive it in the summer months (about 4 to 5,000 miles/yr), it never sees rain or snow. A few times during each winter, if the roads are dry and the salt has been washed off the roads I'll take it out for an hour just to run it.

Question...... Once about every two years, the "low coolant light" will blink indicating its coolant level is low. Typically I add only about 1 to 2 cups (never more than 2 cups) of 50/50 anti-freeze and the light goes off for another couple of years (8-10,000 more miles).......IS THAT NORMAL?

I have replaced the coolant cap several years ago, there are no pools or spots of coolant on the garage floor, no moisture or coolant in the trunk and the car runs great and the temps are always within the normal operating range.

Normal? Concerned? Have it looked at? Does coolant evaporate ever?......any thoughts?

p3230 · 02-21-2018, 09:49 AM

Get a pressure test done on the system to see what is happening.

kk2002s · 02-21-2018, 10:01 AM

System is sealed so you shouldn't lose coolant.
Do you get condensation on trunk lid after driving?
Blinking light low is low. When I got condensation I may have had to add coolant periodically but never lost so much as to get blinking coolant low.

Condensation could be cap leak, purge valve leak or expansion tank crack leak
Then there is everything else associated with the cooling system that could leak.
As mentioned, a pressure test may reveal issue

78F350 · 02-21-2018, 10:59 AM

How old is the water pump?
They often fail slowly and a slow leak like yours would be a symptom.
If it's over 5 years, it would be good to replace even if it isn't leaking.

Paul · 02-21-2018, 11:27 AM

The cooling system includes dozens of rubber hoses and spring clamps, wonder what their recommended service life is.

Brian in Tucson · 02-21-2018, 03:04 PM

Quote:

Originally Posted by Paul

The cooling system includes dozens of rubber hoses and spring clamps, wonder what their recommended service life is.

Day-before-yesterday, and the day-after-tomorrow.

Brian in Tucson · 02-21-2018, 03:06 PM

Quote:

Originally Posted by p3230

Get a pressure test done on the system to see what is happening.

Best answer of the day.

Rob175 · 02-21-2018, 03:08 PM

Thanks guys....I'll have it pressure tested first. Hopefully it's something simple like a old hose or a old clamp leak.

Thanks

patssle · 02-21-2018, 07:56 PM

I've had a leak for 5 years. Have to add a cup or two annually. New cap and valve didn't fix it. But the car keeps running!

Rjbasile · 02-23-2018, 02:22 AM

Same exact thing happens with my 98. Been occurring for about three years now. I just add the little bit of coolant and everything is fine. My mentality is if it aint broke, don't fix it!

kk2002s · 02-23-2018, 04:33 AM

Quote:

Originally Posted by Rjbasile

Same exact thing happens with my 98. Been occurring for about three years now. I just add the little bit of coolant and everything is fine. My mentality is if it aint broke, don't fix it!

Hate to be the bearer of bad news but if you have to add coolant then something, somewhere is "broke"

But doesn't mean you can't just live with it if your not overheating

I live with a minuscule oil leak (RMS I think). More of a thorn in perfection when I see that drop hanging off the engine after a drive

p3230 · 02-23-2018, 05:00 AM

I have the same mentality as you but when I start adding liquids something is wrong and it's time to fix it.

Quote:

Originally Posted by Rjbasile

Same exact thing happens with my 98. Been occurring for about three years now. I just add the little bit of coolant and everything is fine. My mentality is if it aint broke, don't fix it!

Lew · 02-23-2018, 05:11 AM

I still have coolant condensation on my deck lid after replacing the old cap with the newer (04 part #) and the two O rings in the relief valve. I plan on rubber banding a zip lock bag over the coolant cap, and on over the relief valve. Maybe that will tell me where the leakage is coming from.....My coolant cap is very tight!

Burg Boxster · 02-23-2018, 06:51 AM

Quote:

Originally Posted by Lew

I still have coolant condensation on my deck lid after replacing the old cap with the newer (04 part #) and the two O rings in the relief valve. I plan on rubber banding a zip lock bag over the coolant cap, and on over the relief valve. Maybe that will tell me where the leakage is coming from.....My coolant cap is very tight!

A very simple pressure test which pretty much ANY qualified mechanic/repair shop can perform will pinpoint where your problem lies. Cost minimal and time less than 30min.

Good luck

rp17 · 02-24-2018, 06:21 PM

You can actually rent a pressure tester from your local auto parts shops.

Brian in Tucson · 02-25-2018, 05:47 AM

Not all coolant tank leaks are huge. Have you felt around underneath yours? A small leak would account for your problem and should show up a moisture in the carpet. I've been chasing down leaks on my 01 since I got it last summer. Everything in front of the firewall is sealed up, but I still have one from the tank ( which I replaced last fall.) If need be, I'll replace it again, if I can't seal it up. But it's gonna require pulling the tank off (again.) These cars are SO fiddly!

If you do have to pull the tank off, plan on replacing the two segments of hose in front of the firewall that connect to the metal tubes. The hose to the oil cooler has quick connects, mine leaked so I replaced it with a permanent junction. Much better!