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YOUR RESEARCHOh Christ. What let go
Leading reported evidence
Check tank while doing other stuff
Performed · outcome unconfirmed
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Performed · outcome unconfirmed
Quick follow up on this as I just checked my tank while doing other stuff.
Leading evidence: 'Check tank while doing other stuff' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, the most frequently mentioned possible cause is 'oe and a fraction of the porsche part' (1 discussions; 0 report identifying it and 1 suggest it). The most frequently discussed action is 'Check coolant reservoir' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Performed · outcome unconfirmed
I don't see a Porsche logo on the top so the tank must have been replaced by a prior owner before the one I bought from.
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Suspected cause
Behr is a respectible brand, likely the OE and a fraction of the Porsche part.
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49 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Rennlist: 1 discussions
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That's extremely clean looking oil... Did you just change it? Did you over-fill it? This might explain the AOS being overwhelmed... Otherwise i don't know how or why you would just assume that the AOS "let go"... That's not the usual mode of failure (that would be hydrolock/broken rods/cylinders from oil ingestion.
Once it cools off check the coolant reservoir for intermix. Unfortunately MY 2000 had the most problems with heads cracking. I hope this is not the case here.
Just got to y marina. Car was parked here overnight. There�s a large stain where i parked. Drove car here and around last eve as well. Temp never went above 180. Thinking cracked head would have overheated pretty quick way I drive, shifting 4K above and cruise 3500 min.
Yes a lot of coolant parts on that side. If it was a large stain I would guess coolant. You checked the oil level?
A good possibility is a cracked coolant reservoir. Right above that area.
Well now, let's make a list: AOS, Bellow, Cam Plug, Plug Tube, Intermix, Cracked Head, Reservoir. And even oil hydrolock is mentioned, which, outside of the RL echo chamber has happened maybe once on a non-tracked M96. But the day is young, by tonite you're going to be told to replace everything between the flywheel and the MAF, while you are in there of course.
It's clearly not oil. Oil doesn't splash nor does it hiss when hitting the hot parts. I'll go with reservoir for the win (but hope for a hose).
To be fair if he had first said coolant then I think most would have said the reservoir. I am always amazed at the number of perfectly working parts people here seem to replace on their cars.
My fault dudes. I panicked a tad on way out door lol. It�s coolant and as I stated, driving a lower miles old car will in fact rear it�s ugly head of weak parts soon as ya out through paces. Keep ya posted
You can tell by the way it SMELLS ferchrissakes.
I'm still new to these cars but if there's one thing I've learned it is that they don't like to sit. Just like the English cars I used to drive, they need to have blood pumped through their veins on a routine basis.
Schu3507, with regard to your comment above that it never went over 180 and cracked heads, that's exactly what happened to my 99 C2 Cab. On my way to a restaurant in the rain, my temperature gauge warning light started blinking although the gauge was reading 180. Checked the coolant reservoir level in the restaurant parking lot, found it was low and topped up with water in 2 liter soda bottles that I carry in ALL my "fun" cars. Checked the coolant reservoir the next morning and found mayonnaise and, ultimately, a cracked head. Now, you would think the temperature gauge would indicate overheating BEFORE the warning light starts blinking. Moral of the story: the temperature gauges are unreliable on these cars, and when the warning light starts blinking, the damage is most likely already done.
There are several plastic coolant couplers that crack and break with age. Happened to my 2000 996. Big puddle in back. I replaced all plastic couplers and the coolant tank as they found a small leak there as well after replacing the couplers. Good luck! Could have been worse.
Coolant puddle under engine due to cracked and broken coolant plastic couplers.
I just changed my coolant tank in my 99 3.4 as I had the same issue. It is real easy to lower the motor and gives you enough room to get the coolant tank out!
Wait! What? No RL'r has posted you MUST buy the genuine Porsche replacement tank for $700!
Because someone once posted they didn't and it failed. Behr is a respectible brand, likely the OE and a fraction of the Porsche part. They sell hundreds, maybe even thousands yearly.
You don't need the vacuum system. Even if you bought it you'll need a decent compressor to run it. Unless your coolant is old or dirty just raise the rear, drop the engine a couple inches and let out enough coolant to empty the tank, maybe two gallons, then follow the FCP Euro instructions to replace the tank. Top it off while the rear is still raised, check for leaks and drive with the vent bale open, then check it a couple more times.
If you haven't been a DIY'r before this is a good one as I've heard of some paying and indy over a $k for p&l. You can do it all for ~$300.parts and no special tools. Label all your nuts & bolts and where the hoses go.
I have personally seen 3 or 4 behl tanks fail at the seam or the treads. Up to the po if he wants to do the job twice or hope doesnt get a dud. If he wants to save money he can go with the factory mk2 tank thats around $200 and modify the instal. There is a thread somewhere here with details.
Yeah I am in the camp of use the factory part. I rebuilt my engine in my '99 C4 a year ago and in the process put in a new Behr expansion tank. Two weeks ago it started leaking copiously at the seam. I wasn't a believer and was thinking I knew better, but I was wrong. One year and around 6000 miles and it was done.
However, I bought the .2 tank for $120 instead of the .1 part for $500. I get all of my genuine factory parts from Gaudin, they consistently have the best prices. Fit great without modification of the car or tank. Recommend...but the caveat is that I also dropped the engine to tweak the timing so the install was a piece of cake. YMMV with the engine in to get the .2 tank in, I can't speak to that.
Chuck
Bad:
New .2, good:
Sorry, but unless you're lucky that tank will fail in a year or two. I bought an "OEM" German tank that was supposed to be exactly the same as Genuine Porsche. It wasn't. It didn't last two years and probably around 5000 miles. It's not a fun job to repeat. I don't think I could have used the MK-II tanks as my car is a cabriolet and there is more stuff in the way (I think).
thanks for vote of confidence 😂 . If the Porsche is so superior mine went in 30k? He used same one and races the vehicle it�s in. I�d imagine that�s going threw some serious heat cycles? Also why are we insisting Porsche part is superior when it also fails. I don�t see the logic in spending nearly 53% more for a part they can�t warranty and garuntee won�t fail either. Seems hit or miss in my opinion of what I�ve read. Now being said if a Porsche one lasted 30k be fantastic. Again from what I�ve read some do and some take a turd earlier so? What�s the determining factor? Driving in cold weather and heat cycles? Beats me but I�ll roll dice once I guess. Happy Friday y�all
Not Mahle/Behr, and not in PRC, wish I would have taken a photo but the mfg and COO is cast into the top of the tank (not a sticker) and I'm not taking it back out! The Porsche one says made in Germany and the plastic has a different feel. I had the same thoughts as every one of the naysayers above, like I said, I thought I knew better but I was wrong. Original 1999 Porsche one in mine lasted 21 years and didn't actually fail, I proactively replaced it when the engine was out the first time.
Here's the one that failed.
Well, mine is the $700 MK1 that is 23 years and 180k miles old , and is still leak-free and the cap fits good, so there is that data point for the " Genuine Porsche Part"....lol
When/if it fails I'll go with the $120 Genuine Porsche MK2 "upgrade"...
and another datapoint. I changed mine proactively at 20 years (around 70k miles). It was still fine, but I didn't want any surprises when on a road trip. The mileage is less of a factor than the age and number of heat cycles.
Lots of threads on this. This advice should be a sticky, just like frequent oil changes, bore scope recommendations on PPIs, use the non-metal water pump, UAOS, etc.
Thank god for experts on Rennlist, my life with my 996 has been pretty great, as I have taken many recommendations and none have led me astray.
Quick follow up on this as I just checked my tank while doing other stuff. The reports here of bad tanks are certainly from knowledgeable members of the forum with more experience than I have.. Still, I would not be able to pay $600+ for a tank and would take my chances, maybe even with a URO tank (with FCP guarantee) as I don't see any specific reports of them failing, or a Mk2 tank.
Here's my tank. I knew the cap is not Porsche, I believe it is Rein. I don't see a Porsche logo on the top so the tank must have been replaced by a prior owner before the one I bought from. Fingers crossed.
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