biosurfer1

I've had my 968 about a week now and when I had the PPI inspection, the mechanic said there were some small oil leaks and the water pump was leaking. The water pump was just changed so the mechanic who changed it said he would look at it (different mechanic from PPI). I dropped it off this mornign and shortly there after got a call from him stating there was no water pump leak nor any signs of a coolant leak, but there is a "major" oil leak coming from the balance shaft. Confused, I am trying to get a hold of the PPI mechanic because in my mind, a coolant leak and oil leak are very different and should not get mixed up. I am wondering what the PPI mechanic saw to claim the water pump was leaking.

I am also wondering why, if there is such a major oil leak, is there apparently no sign of it on my garage floor nor has there been any drop on the oil dipstick? I have driven it roughly 500 miles since I got it and checked the garage floor and dipstick frequently...everything seemed normal.
The previous owner (who originally had the work done by the mechanic) said he told him everything was perfect back in Novemeber.

Is it possible for the balance shaft to go from "perfect" to a major leak in less than 6 months?

Also, one thing the mechanic mentioned is the PO had the timing belt re-tensioned and he didn't understand why that was needed since the 968's have automatic tensioners? From my research, even with the automatic tensioners they still need to be checked 1500-3000 miles after replacement...correct?

tamathumper

The balance shaft belt should be retensioned after 1,500 miles, the timing belt has a hydraulic tensioner on it already so is generally OK, but it's not a bad idea to give it a look-see at the same interval to make sure it's not getting rubbed by something.

On my car, and on a few others I've heard of (anecdotally), the car can start to weep oil from various orifices if it has synthetic oil added after years of running conventional oils. My car came without a single leak and a big note in the glove box saying "If a mechanic recommends synthetic oil, fire him." The maintenance records indicated it was taken in for multiple oil leaks, and that conventional oil was added and the leaks all stopped. The mechanic's note on the slip indicated the synthetic vs. conventional theory/advise.

I put Mobil 1 in it and immediately had several weeps of oil whereas before there was none. I put conventional in it on the second change and the seeps stopped. Most recently I've put Mobil 1 15W 50 into it, and I'm "monitoring the situation".

Yours may be a case of a new leak caused by synthetic oils added when you purchased the car?

docmirror

^^ Yup, good words ^^

More than likely you had dino oil in there, and someone put some synth in. The lower balance shaft seals are notorious for leaking as they get a fair amount of heat from the headers, and then cold soak at the bottom of the engine after it cools. The re-seal job is not difficult but I would not recommend it unless you are young, or you have a lift at your disposal.

Clarks garage has a write up for balance shaft removal and replacement that is quite useful. You will need all the seals from the front to the back of the shaft, a bit of Yamabond or equivalent, and I suggest a new balance belt unless the one you have on is fairly new. Another good WYAIT job is the right side motor mount. Don't go cheap on that either as the low cost ones tend to vibrate after a short time(ask me how I know).

Roger at 928sRUS has the list of parts for the lower balance shaft re-seal, and he can get them to you in a few days at good price. He supplied all my bits. 817-430-2688.

biosurfer1

Thanks guys...I will have to check on the oil. I know it was changed within the last 3000 miles but I'm not sure if it was syn or not and what was used prior to that...I'll have to check the records.

Thanks for the advice on the balance shaft seals. I'm waiting to hear how much the mechanic wants to change them then I'll decide if I want to DIY. I usually do all my own work but have learned to pass it off if its not worth the time.

I hate conflicting mechanic reports for two guys I don't know. Both have good reputations but when one says there is an oil leak and the other says its a coolant leak, it's very frustrating.

docmirror

The job isn't too bad. Fitting your fingers up in the motor mount area and the balance shaft bolts gets a bit dodgy but it can be done on your back. I just took out the right MM and replaced it while I was down there. Don't forget the heat shields going back in, and then the shaft tension adjustment is a bit tricky as well.

biosurfer1

Thanks. I think I am going to tackle it myself... I talked to the PPI mechanic and this is the main reason I don't trust almost any mechanic. He says there definitely a drip of coolant but maybe the gasket swelled up and it working correctly now?!? The other mechanic says there is no indication at all of any type of leak?!?
I also got quotes for the balance shaft seal replacement and one tells me 3-3.5 hours, the other says 6+.

Screw it, I'll just fix it myself and learn something in the meantime. All the mechanics point at each other and of course, neither was wrong in their assessment according to them. Waste of time and money to trust them.

tamathumper

There are a bunch of spots what a mechanic might choose to call "the water pump" could leak, including all the points the hoses attach at the top - heck, I think there's even an o-ring inside the top fitting that can cause a leak. Often, just tightening the hose clamps is enough to stop it, and maybe that's what happened?

RajDatta

While doing my recent timing/bs belt change, I saw that the new interval for re-tension is 3k miles. Interesting..

docmirror

As the first time job, I would say 6 hours is pretty accurate. Now that I've done it, I could do it around 4 hours, but 3.5 sounds right for a pro mechanic with all the right tools. Roger will have my parts list from when I did it last year, and I got everything cause I don't like oil leaks. I now use syn oil with few issues. Only a very slight seep from the back of the cam cover.

Read up at Clark's garage. You prolly find a half dozen other gotchas while you're under there. I straightened the tabs that fit the rocker covers, re-routed the wiring to the starter, replaced the starter pick wire(this is important as they lose insulation and can cause an uncommanded starter engagement, ask me how I know), cleaned the bottom of the engine, re-fit the bolts to the power steering, and mess with the grill which is usually trashed. Roger has a grill for sale too.

mbardeen

As to why oil can leak and not show up on your garage floor -- the car has a drip tray to catch such occurrences.

Getting in and doing it yourself is a good way to get intimately connected to your car. You can find the workshop manuals here:
http://www.2010.cannell.co.uk/manual...s_porsche.html

biosurfer1

thanks...that was the first thing I downloaded months ago before I bought.

I know it has a drip tray but I thought after 500 miles driving (quickly at times) I would have seen at least a drop or two. Maybe I'm just still in a 914 mind and used to seeing drips on a regular basis.

docmirror

Not to be pedantic, but it's not a drip tray. It's a protective plate, to keep the underside from damage and to help cooling air flow.

mbardeen

The one I'm referring to sits right behind the "batwing" and is plastic, semi-concave, with holes that have lips around them... effectively holding whatever small (or large, in some cases) amounts of fluid that happen to fall from the engine and preventing them from hitting the ground.

So while the primary purposes may be protection and cooling, it also functions as a drip tray.. But I'm not pedantic so you may call it whatever you like .

docmirror

Ectually, to move into the pedantic realm, having a tray that retains flammable fluids is counterproductive. You'll find a couple of drain holes at the low point, at the ends of the troughs that drains off fluids rather than retain them.

It's two functions are to protect the bottom areas of the engine from road damage, and to allow an area of low pressure to form under and just behind the engine so that hot air exiting the radiator is drawn down and out of the engine bay.

/pedantic

mbardeen

Yes, I can see your point...

But please explain that to the 20(?) years of accumulated powersteering fluid, oil, and road grime that I pressure washed/scrubbed/scraped off the darn thing.