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Old 01-03-2015, 02:00 PM   #1
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Beater Boxster clutch diagnosis...??

I went for a ride this morning on the freeway arrived at my destination and parked. When I left and entered the freeway my RPM's jumped to 6000 and I was on 3rd. I rode for the next exit out and the car was smoking and and the car didn't seem to engage with the motor (slipping).

After I parked for awhile I started the car and there are no CEL on or any other fault light showing. I'm soliciting your opinions based on what I've said. Do you think it's the clutch gone bad? Prior to this incident the clutch never felt like it was slipping.

Any post test I can perform? I had Beater towed to my home and it's now in the garage. Since this isn't my primary car I'd like to do the repairs myself. I have tools and have access to more.

Any help would be greatly appreciated!!
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Old 01-03-2015, 03:22 PM   #2
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Year and transmission type is usually helpful. You said the car was smoking. Could you smell the smoke? A burning clutch usually fills the cabin with acrid smoke that tends to stick with you awhile. Did your brakes get spongy (thinking clutch slave cylinder leak here). I've been through a few clutches and they warned me by slipping a bit in higher gears (second gear a favorite) under load and then catching again as the load was reduced.
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Old 01-03-2015, 03:34 PM   #3
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Jamesp,

My car is a 2002 Base model Boxster, 5 speed manual. I could see the smoke coming from side vents after I stopped. You're right the car still has the odor of something burnt. This was a couple hours ago.

I didn't notice the brakes getting spongy during the event but I can check now if that makes any sense?

Should I start the engine and see if the brakes feels differently?

Any feedback is greatly appreciated.

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Year and transmission type is usually helpful. You said the car was smoking. Could you smell the smoke? A burning clutch usually fills the cabin with acrid smoke that tends to stick with you awhile. Did your brakes get spongy (thinking clutch slave cylinder leak here). I've been through a few clutches and they warned me by slipping a bit in higher gears (second gear a favorite) under load and then catching again as the load was reduced.
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Old 01-03-2015, 04:29 PM   #4
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Spongy brakes *could* mean that the clutch slave cylinder (which is part of the brake hydraulic circuit) is spraying hydraulic fluid onto the clutch / flywheel assembly. This is a bit of a stretch, but entirely possible with the sudden onset of smoking. If the engine was running normally, and the smoke was coming out of the side vents (not any out of the exhaust!), then starting would be ok, but not the course I would choose first. The only data I could imagine by starting that would be gained is a coolant leak and steam. If you smell burnt, and not sweet (like maple syrup) then a coolant leak is out. Look under the car where the engine and transaxle meet (just in front of the bell housing by the back of the engine) is there a drip of fluid there? If so soak it up with a paper towel. What color is it?, clearish with a few black specks would indicate brake fluid. Uniform dark brown or black is engine oil. I'm not sure how good your nose is, but if you know the difference in smell between brake fluid and engine oil that's a dead giveaway also. So I'd start by 1) smelling the smoke - does it smell burnt or sweet? if burnt then it's likely the clutch, 2) is it leaking fluid? if so then what is the fluid, brake fluid or oil? In general, the jumping RPMs indicate you are in for a clutch job due to wear or contamination. A coolant leak would not result in increased RPM without a corresponding increase in speed. If the transmission were shot I'd expect lots of sound followed by no forward motion at all.
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Old 01-04-2015, 12:25 PM   #5
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When clutches wear out there is a tendency for them to slip at low revs in the higher gears. This can go on for a long time (months). With a sudden onset of a loss of drive it indicates something else has occurred. With smoke bellowing out, a burnt smell and a loss of drive it points to a fluid or burnt disc that needs immediate attention. It could be a blown rear main seal which allows oil to soak the clutch lining.
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Old 01-04-2015, 01:31 PM   #6
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Gentlemen,

Thank you for taking the time responding. I took a look under the car with my iPhone and took a few photos. I see fluids leaks all over the place! I'm not sure what's going on with that wiring, I believe it is connected to the 02 sensor.

I wasn't clear if I could start up the engine and also pump the brake to check for sluggishness. At this point it won't matter much, just more fluid to clean up I suppose.

If I'm not providing a photo that gives the proper angle let me know and I will retake the shot.

I have the Wayne R. Dempsey "101 Projects for your Porsche Boxster" and the Bentley Porsche Boxster manual for reference. I'll try to keep up with your technical terms.

Once again thank you, it's greatly appreciated!







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Old 01-04-2015, 04:41 PM   #7
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It looks like you have oil or hydraulic fluid running out between the engine and trans. not a good sign. If its oil, its the imsb or the rms, both of which could oil the clutch and cause the slipping, but since it could be the imsb, i wouldnt even start the car. In any event, you are going to have to take out the tranny to diagnose the problem and replace the clutchnplate at least.
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Old 01-04-2015, 04:58 PM   #8
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I guess the next step is to start borrowing floor jacks. Question.. if it's the IMSB will this trip a CEL? Thank you.

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It looks like you have oil or hydraulic fluid running out between the engine and trans. not a good sign. If its oil, its the imsb or the rms, both of which could oil the clutch and cause the slipping, but since it could be the imsb, i wouldnt even start the car. In any event, you are going to have to take out the tranny to diagnose the problem and replace the clutchnplate at least.
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Old 01-04-2015, 07:02 PM   #9
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Quote:
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I guess the next step is to start borrowing floor jacks. Question.. if it's the IMSB will this trip a CEL? Thank you.
No. Pull the oil filter and open it up and check for any foreign material.
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Old 01-05-2015, 03:13 AM   #10
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Looking at the picture I don't see any drips, but you clearly have leakage. I think you are in for a clutch, likely an IMSB seal and a rear main seal. I will tell you right now the most important thing to do before messing with the IMSB is to lock the engine at zero timing before you start. Read that last sentence again! If the engine is not locked at TDC, the valve springs will try to rotate the cams when the IMSB is loose, at TDC the valve springs cannot rotate the cams. If the cams move with the IMSB loose (you don't remove it to change the IMSB seal, it ends up just being loose) you can lose valve timing and you are in a world of hurt. Skip the drama and set the engine to TDC first thing before disassembly. Installing the seals and clutch parts is simple, just lots of nuts and bolts with plenty of various torque settings and seal installation depths to pay attention to.
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Last edited by Jamesp; 01-05-2015 at 01:54 PM. Reason: grammer
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Old 01-05-2015, 06:59 AM   #11
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Hello,

i agree with JamesP. That seems to be a leaking IMS seal, and or rear crankshaft seal.

Concenring the smoke. What is the mileage of the car and when was the clutch replaced the last time?

If you want us to check the the clutch slave cylinder at the transmission for a leakage you'll have to take a photo of it.

Regards
Markus

Last edited by Smallblock454; 01-05-2015 at 07:02 AM.
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Old 01-05-2015, 12:47 PM   #12
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The wiring looks fine except the outer protective sheath is oil-soaked. That's why it looks like eye lashes with mascara on...
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Old 02-01-2015, 12:12 AM   #13
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Pulled the transmission out and the clutch and flywheel are toast. I'll be purchasing both parts for replacement. The leak does seem to come from the IMS seal. If I remove the IMS bearing cover do I still need to be at TDC? I want to check if I have the original IMS bearing in place. The previous owner said he replaced it with a "ceramic"? type. I could never get paperwork from him supporting that statement. I don't know what the original cover should look like, I'm including photos of mine.

You can't see in the photo but there is a bead of silicon around the flange. This doesn't not look like a factory job, more like it leaked after somebody removed the cover.

Any thoughts would be greatly appreciated.

NOTE: Beater Boxster is: 2002, Base, 5 speed with approximately 85k








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Looking at the picture I don't see any drips, but you clearly have leakage. I think you are in for a clutch, likely an IMSB seal and a rear main seal. I will tell you right now the most important thing to do before messing with the IMSB is to lock the engine at zero timing before you start. Read that last sentence again! If the engine is not locked at TDC, the valve springs will try to rotate the cams when the IMSB is loose, at TDC the valve springs cannot rotate the cams. If the cams move with the IMSB loose (you don't remove it to change the IMSB seal, it ends up just being loose) you can lose valve timing and you are in a world of hurt. Skip the drama and set the engine to TDC first thing before disassembly. Installing the seals and clutch parts is simple, just lots of nuts and bolts with plenty of various torque settings and seal installation depths to pay attention to.
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Old 02-01-2015, 04:18 AM   #14
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YES before removing the cover be at TDC! Removing that cover while not at TDC is where the drama starts! Even more drama than is in this post.
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Old 02-01-2015, 04:22 AM   #15
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One more bit of TDC trivia. For those storing their cars for extended periods, set the timing to TDC to unload the valve train while in storage.
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Old 02-01-2015, 10:35 AM   #16
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Imsb

Looking at the IMSB nut it looks like a stock nut to me...meaning Porsche. With as much dirt and oil as you have I doubt a new bearing was installed. If it was done a long time ago and the bearing was ceramic it would have to be a LN bearing.
I do not think Jake ever offered a bearing with a nut like you have. He uses Torque nuts. You may want to asking him if he ever offered a nut option like the Porsche stock nut. If I had to bet I would guess the IMSB has never been changed and the clutch and fly wheel has never been off the car before. See attached
http://lnengineering.com/media/catalog/product/cache/1/small_image/504x504/9df78eab33525d08d6e5fb8d27136e95/1/0/106-08.4.JPG
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Old 02-01-2015, 12:19 PM   #17
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Not related to the oil leak but certainly a factor in avoiding a future disaster - check the free play on the DMF. There is a very specific procedure and measurement. It is often done incorrectly .Badly worn DMF= doom.Measure both 'rock' & 'rotational' play.
They normally last around 90k miles+/-
https://www.youtube.com/watch?v=uLp6nlYMssA
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Old 02-01-2015, 01:32 PM   #18
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Did you clean the RMS and IMSB areas before taking the picture? I 'd order a new RMS and release bearing as well. Was the car parked for a number of days before the 'event'?
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Old 02-01-2015, 09:56 PM   #19
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I guess it all points to getting the IMS bearing replaced. I know there are a ton of threads on this topic. I'll start researching on replacement manufacturer and tooling to do the job. I'm working with my indy mechanic on this. He's never replaced one before so I may be looking at other options. I'd hate to put it all back together only to have it all removed to install the IMS bearing.

Thank you for all the feedback, it really helps me out, at least knowing what section to read in the manuals.

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Old 02-07-2015, 07:32 AM   #20
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while you are there, it would be prudent to drop the oil pan and check for debris which may have settled in it. for the cost of a tube of silicone, it is worth the effort.
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