Oiling issue during autocross
 

In ran my 986S in an autocross last weekend and experienced an unusual situation that perhaps you can help me with. It is an oiling issue I would expect to see on a track running sticky tires vs autocross on street tires.

I am running summer street tires (Sumitomo HTRZ3). PSS9 suspension. Oil is changed regularly, no metal flakes, engine runs very strong.

After a couple of runs I noticed a ticking sound, like a lifter tick after each run. Right after one of the runs, when there was the ticking sound, I turned off engine and checked the oil level with the electronic gauge and dipstick - the oil level was under the bottom level mark. The car never had a starting problem or warning light.

The tick went away after the car sat a minute or so, oil levels were right up to a little over the middle of the stick and gauge, and the engine ran extremely well.

During runs I was in second gear the whole time, and was at high RPMs a couple of times - not sure how high, however never hit rev limiter, my guess was around 6k tops.

Before autocross (and typically) I checked the oil level when car was cold, was a little over the middle (i.e. in between low and high lines) with dipstick and gauge. I have a relatively fresh change of Mobil 1 10w-40 I did in around March.

My theory - I have been running my oil level low by checking it cold vs hot. Is fine on the street, but G's and high rpm's cause low oil symptoms to show up. When hot more oil gets into various parts of engine vs sitting in sump. The manual says to check it warm, after a couple of minutes for oil to settle in sump - I have been using wrong technique by checking it cold.

I cannot imagine I need a deep sump, or accusump - again, my thought is that I was a little low on oil.

Has any experienced this, or can provide some insight?

Thanks!

Gary

I had a very similar ticking with my engine and I believe what you're hearing is a lifter. My ticking also started after a track session.

It was never noticeable on the street but it got progressively worse and would be easy to hear after coming off the track.

With over 130,000 miles on the engine, I just let it go and kept driving the car to/from the track and racing.

Ultimately (at 136,000 miles and 89 track days), a lifter failed and my engine had to be completely rebuilt including replacing all of the lifters and the lifter carrier/cradle. Here is the story: http://986forum.com/forums/general-discussions/52798-engine-failure-pics.html

I wouldn't worry too much right at this moment, but an engine noise is never a good thing and I'd recommend that you have your engine checked to have the ticking source identified so you know exactly what's going on.

thstone,

Thanks for the feedback, I remember reading what you went through and hoped you would reply. Is this something to fix preemptively, or just let it go? I saw you asked similar questions with no answers.

I have only heard the tick when oil was really low after the autoX runs, hopefully I am right and it was low oil. Only way to find out is to keep driving it! Hhmm - wonder what 3.6 rebuild costs... :-)

Did you drive this car over the past winter where temps were near or below zero?

Its a reconstruction at our level and if its elective its17K, normally 18,500.00 for a Stage I 3.6, my Stage II is 3.8 and about 2K more expensive with the "elective discount".

I am so tired of every single engine we see being blown to hell that I am offering big discounts for elective work. This year we have not had a single elective build. The failures are killing productivity; because we can't find the core parts to make up for all the broken stuff.

So is it a lifter failing or debris in the lifter?

Trying to understand how it can come and go?

Does the heat or thinning oil allow bypassing the internal lifter seals?

Mike

I have the same issue after the car is tracked (or AX'd in really hot days).
The problem is that the oil temperature gets too high and causes a significant drop in oil pressure.

For my car (Base 986, running Motul 300v 10W40, EBS oil baffle, Boxster S Oil cooler) the ticking happens when oil temperature hits 230F.
At this temperature or above, the oil pressure @ idle drops bellow 10psi and the tick becomes audible.
Under these circumstances - coming back to the paddock or after finishing an autocross run - I keep the revs above idle where oil pressure is 15psi or above (no ticking)
Of course, this is no real solution.

At this time, I'm hesitant to install a 3rd radiator. I wonder if using 15W50 would help minimize the oil pressure drop when the oil temp hits 230-240F

I've added a temp gauge and oil pressure gauge -- I'll have to keep an eye on
those my next track day.

contemplating adding a fan and external oil cooler.

As I have the S -- I already have 3 coolant radiators.

Mike

Sounds like a lifter ran temporarily dry.

I had that happen at a PDS where we were doing successive skidpad exercises in one direction and oil pooled on one side of the engine. I was also running with oil level 1/2 way on the gauge. One of the local performance shop owners recommended to always run with oil at the very top of the measurable gauge without overfilling to avoid running lifters dry or worse. I followed his advice and never had this issue again.

Always check oil when the car is warm.

Yes. Very important.
Unfortunately for me, that did not prevent the issue.

My main point was to say that the ticking is reason enough to take the car in and have it evaluated.

To answer your question, if the problem is the lifters, my understanding is that they can be replaced preemptively and may not require removal of the engine. Of course, you'd have to take everything (miles on engine, planned use, budget, etc) into account to determine what the best path might be for you.

If someone says its the lifters, be sure to ask the mechanic about replacement of the lifter carrier/cradle also as there have been reported instances where new lifters were installed in a used carrier/cradle and shortly thereafter one of the new lifters failed.

With all of that being said, a 3.6 upgrade sure sounds tempting, doesn't it?

[QUOTE=Jake Raby;415858]Did you drive this car over the past winter where temps were near or below zero?


Jake, no I did not drive it during the cold winter, when I did drive it temps were above 40. I will call your shop sometime soon to learn about what you can do add more fun and increase reliability. I live about 2.5 hours away, may drop in one day!
Thanks, Gary

[QUOTE=thstone;415935]My main point was to say that the ticking is reason enough to take the car in and have it evaluated.

I agree - will get it checked out. I am confident I just didn't have enough oil, it only ticked when level in sump was very low, stopped when sump level increased.

3.6l in a 986 sounds awesome!! I can feel my wallet shaking :-)

Topless - Based on conversations so far this is the consensus, however I am still going to get it checked out. Nevertheless, I have changed my oil checking technique.

I have been interested in getting oil pressure and temp gauges anyway, this is a good reason to go ahead. Also considering a deeper sump/baffle/accusump, doing homework now.

[QUOTE=heymanwatchthis;415967] Sounds good... Call and set up a time for a tour at least a week in advance.. We are far from a "normal shop".... You can't get within 1/4 mile of the shop without a gate access code :-)

First thing I did when I got my Boxster s for the track was to add 1/2qt deep sump and EBS baffle plate.

I run amsoil 20w/50 racing oil.

As mentioned earlier I also added oil pressure and oil temp gauges.

I run my oil fairly full. I'd risk an aos issue before spinning a bearing or collapsing a lifter.

I also went with a under drive pulliy to protect my power steering pump.

Not a fool proof plan, but I'm hoping it's good enuf for now .

Mike

I'm running the EBS baffle but not the deep sump extension. I run my oil about 2-3 bars below the top. I have a UDP but haven't installed it yet. I'm still fairly new so I doubt I am generating too many excessive lateral g forces :)

Mike,

Why did you get 1/2 qt vs 2 qt sump extension? I am considering this and baffle as it seems like cheap and easy upgrade.

Also regarding gauges - how did you get the signal? Did you need to set up sensors, etc or is it plug and play?

I'm happily going down the 'slippery slope' - this stuff is fun!

Thanks, Gary

Running the oil level low is only beneficial if you have an extra deep sump and you just want to drop the oil level in the sump while retaining the same level of oil in the engine.

Don't just throw a heavier oil at it, use an oil with the proper viscosity index for the temperatures that you'll be running.

Good questions.

I have a track membership
~30 miles from my house and this is my drive to track car.
I've also lowered it about 1".

I wanted to make sure I didn't have issues driving to/from the track
With pan clearance.

I run the 20w/50 here based on the Texas weather and anecdotal data that my 924s Chumpcar holds better pressure on track even after 24 hours of thrashing.

Maybe coincidence but moving to Amsoil and the 20w/50 or sometimes 60.
We also added a 2nd oil cooler.
We haven't had engine issues on track, since.
Many factors come into play but we lost two engines prior to this.
Not exactly scientific, but
Call it superstitious, I just like to stick with what has appeared to
have worked in the past. My guess it's a combo of all three and has a lot to do with keeping absolute oil temps lower.

As far as gauges, I had to add senders to engine,
There are some plugs at the top of the heads.
Probably other places to tap from, but they were the easiest (but not that easy)
With the engine in the car.

I'll try to snag pictures next time I get a chance.

Mike

Some good feedback from all. I like Tom have had my engine rebuilt recently after say 30+ track days and 8 or so AX's. I read all these posts and talk to as many knowledgeable people about the 986 oiling issues as I can. The inevitable thing I have realized is that we all are using a "street motor" for performance driving. It's not a question of if, it's when. The consensus seems to be that once a dry sump system is created it will solve these issues. Until then everyone has differing opinions of what works and doesn't. I just know if I use my car for track use more than less I'm that much closer to spending 10-12K on a rebuild. Nothing we all are doing is cheap.

Topless has some great insight on how to preserve your motor and get the most out of it. I try to now employ some of his tactics as I believe he has over 300 track hours on a 2.5. Hard to argue with that. His basic premise is go easier where you can. A lot of times down gearing seems faster but may not be. Keep you RPM's in G force situations down where oil will move due to lateral forces.