[flash]

it's definitely not pretty, and i would stop where you are - forget about the track, i wouldn't take that to the grocery store until i figured out what it is - something is very wrong there - mine isn't that clattery even after sitting for 3 months

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[rl968]

thanks...the problem is that there are very few people who are qualified to work on a 968 engine? My mechanic has a lot of experience with Porsche engines, just not the 968. We are trying to understand the oil flow in the engine and where the problems might be coming from. What if the problem is happening before the oil goes to the lifters, then I've changed the lifters for no reason and they aren't cheap (16 of them at $20-$30 a pop.) Just too expensive for trial and error so want to try to pin it down.

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[flash]

you're not far from pete

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[madridcab]

Mine suddenly sounded like that, had it flat bedded to my mechanic...(who laughed at me being over cautious..) Verdict was hydraulic lifters on the exhaust side, I have the bill here somewhere, but was not too bad, I believe south of $1K - I decided to do the variocam pads and chain at the same time. All quiet and drive with peace of mind now..

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[rl968]

Just an update here: We cracked the valve cover and everything looks normal and in great shape. Took j-tube off and it was in perfect shape (no cracks), oil pressure relief valve also in near new condition. Doesn't appear to be a lifter problem either and instead potentially an oil starvation issue, but not pinpointed yet. Next step is to look at the bottom end. Plan is to replace rod bearings and oil pick-up tube ("while you are in there"), pan gasket which weeps also going to get replaced as well as oil level sender, whose light comes on the dash periodically. Don't know when rod bearings were done last, if ever, so with 137k miles on the clock, seems like it's overdue.



Hopefully this thread will help others diagnose similar problems, I'll provide an update when the work is done in the next week or so.

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[Cloud9...68]

Yes, people say that rod bearings are due at about 100K miles. Not sure I buy it, but better safe than sorry. I just took mine out (116K), and they look to be in very good shape, with no obvious scoring even much in the way of scratches. But my oil pressure was on the low side, so maybe they're thin. I'll measure them when I get the chance.



I'm sure you're aware, but you have to drop the front suspension to get the oil pan off, which means an alignment. It's not a terribly difficult job, but very time-consuming. If I remember right, the hardest part of it (when I replaced my engine mounts several years ago) was getting the sway bar back on.



Good luck tracking down your problem - sounds like a fairly elusive one.

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[rl968]

yeah, thanks. Alignment was on the list, needed one before this work anyway. I'm pretty confident that having this work done will solve the problem. There isn't much more it can be. I'm not doing the work myself, have a friend working on it for me.



I've had this car for a year now and have done a lot of work to it, probably more than has been done to most of them in their lifetime. I'm hoping after this the car will be fully sorted with the only defects being some cracks in the dash and non-working driver side speakers, both of which are trivial IMO!

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[rl968]

Issue has been resolved. The issue was related to oil starvation. The lifters were making noise, but it was all of them and only because they were not getting enough oil, not because they were bad. The pick-up/siphon tube was cracked at teh top and bottom (see pics), pretty nasty. We didn't have much clue here as the oil pressure gauge was reading relatively normal at a little above 4 at 3000 rpms. After replacing the tube and the rod bearings, pressure is running at about 4-3/4 and a little over 3 at idle. Runs quiet as a kitten (see before/after video.) BTW, this is a not a prevalent issue, but it is fairly common. If anyone needs a mechanic in the New Jersey area, let me know, I've got a very good one!!



One last thing, the rod bearings were in pretty good shape, hardly any scoring, even in #2, but we replaced them anyway given it was all opened up and the parts are relatively cheap.











Before:

http://www.youtube.com/watch?v=RwLqzsXM_wg



After:

http://www.youtube.com/watch?v=nU9W0DBXBno

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[tim944s]

Awesome! Great thread!

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[tamathumper]

In my experience, the oil sender's just not in a position that tells you when you have oil pressure problems at the top end. <img src="/forum/images/smilies/968/sad.gif" class="smilie" alt="" /> Glad you got it sorted. <img src="/forum/images/smilies/968/smile.gif" class="smilie" alt="" />

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[Cloud9...68]

Congratulations on solving your problem. You were smart not to drive it much in that condition. I've heard the oil pick-up tubes are weak spots in these engines, but I haven't heard of too many specific cases of actual problems.

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[RS Barn]

Turned out to be cracked oil pick up tube

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[flash]

and it's this kind of thing that made me say "stop driving" - glad it was resolved

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[Cloud9...68]

Since reading this thread, I took a closer look at mine, and it appears that there might be a hairline crack developing in it as well. It's hard to tell, and it would be impossible to convey through a photograph, so I may have to take it to somebody locally with some experience looking at these things, but to me, it looks like a small crack may be starting. Will most likely add it to the long list of things I'm replacing or upgrading.

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[rl968]

it's not an expensive part so might as well replace it if there was any doubt. Pete was a huge help on pointing me in the right direction!!

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[RS Barn]

I'm not a fan of adding braces. The tube is very thin and welding a bracket to tube will only add stress.

Just replace at rod bearing service intervals.

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[mbardeen]

Last week I started my engine up after an extended rest period (about two months) and all was normal. I moved the car out of the carport, turned it off, cleaned the carport floor. When I returned about 10 minutes later to move the car back in to the carport it started making a noise strikingly similar to what's described here -- definite metal on metal clacking. Letting it warm up some did nothing to reduce the noise.



I've gone through and checked the timing and under the valve cover, but did not see anything out of the ordinary. Cranking the engine by hand doesn't reveal any abnormal sounds. Oil pressure is reading right around where it always has, 4 lines or so on the gauge at startup.



So I'm thinking that it's the oil pickup tube that has gone to heaven. Does anyone know of a good way to check this without removing the pan and all that involved?



And related question -- to remove the crossmember, I'd have to support the engine from above?

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[vliegwielolaf1234]

No easy way to find out , as far as i can tell , dropping the oilpan is the only way .



And yes you have to support the engine from above when you drop the crossmember .



Lifter noise sometimes won't go away until oil has been warmed up .

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[DaveN]

If you have 4 steady bars then one would assume the oil pump must be picking up oil, no?

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[flash]

i've had my lifters make a racket on occasion. once i drive it for a minute it goes away. they don't like to sit for long.

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