blown engine
10-15-2015, 10:23 PM
#422
Rennlist Member
I am still loving my 996 even though I feel like I'm living on the edge with my second IMSB engine.
02-23-2016, 12:38 AM
#424
Latest updates:
- Crank magnafluxed and cleaned. It's in good shape.
- All IMS, timing chains, and broken pieces sent to LN engineering and the super expert in GA
for careful analysis. It was found that the bearing was a collateral damage due to excessive slop on the IMS bearing end, snapped IMS paddle and 1/4" stretched IMS drive chain.
- Despite the finding, Charles kept his word that he would help me rebuild this engine. "Help" may be a weak word if you consider what Charles has to offer
- Placed order for the 3.8 Nickies and other goodies
- Crank magnafluxed and cleaned. It's in good shape.
- All IMS, timing chains, and broken pieces sent to LN engineering and the super expert in GA
for careful analysis. It was found that the bearing was a collateral damage due to excessive slop on the IMS bearing end, snapped IMS paddle and 1/4" stretched IMS drive chain.- Despite the finding, Charles kept his word that he would help me rebuild this engine. "Help" may be a weak word if you consider what Charles has to offer
- Placed order for the 3.8 Nickies and other goodies
02-23-2016, 02:51 AM
#425
IMSB completely submerged in engine oil
In the photo below you can see the oil dip stick sleeve installed in the engine case. There's a small hole near its end. That hole is very close to the "MAX" mark on the dip stick. If you extend a line horizontally from that hole, you can imagine that the IMS and IMSB are completely submerged in the engine oil when the engine is at rest. Just thought that was interesting. I always thought only part of the lower portion of the bearing is submerged in oil.
02-23-2016, 12:00 PM
#426
^^ Cool observation. When the engine is running I believe the oil level is a bit lower than when the motor is shut down (with oil circulating throughout the engine). How much I don't know...
02-23-2016, 12:30 PM
#427
Drifting
Ahsai, Useful fact on a subject where assertions often overwhelm the facts.
You are correct ,I too recall some big names saying( the lower 1/3 of) the bearing is submerged . Perhaps they meant 'while the engine is running' ? That too is confusing because Pedro's video simulation shows oil being spun out of the bearing as soon as the engine is spinning.I'm not saying Pedro's video is an accurate representation of what really happens to the oil around the IMSB, just that it is interesting and nobody has done any more convincing video of the issue yet?
You are correct ,I too recall some big names saying( the lower 1/3 of) the bearing is submerged . Perhaps they meant 'while the engine is running' ? That too is confusing because Pedro's video simulation shows oil being spun out of the bearing as soon as the engine is spinning.I'm not saying Pedro's video is an accurate representation of what really happens to the oil around the IMSB, just that it is interesting and nobody has done any more convincing video of the issue yet?
02-23-2016, 08:16 PM
#429
Intermediate
Join Date: Jan 2016
Posts: 31
Likes: 0
Received 0 Likes
on
0 Posts
Ahsai, Useful fact on a subject where assertions often overwhelm the facts.
You are correct ,I too recall some big names saying( the lower 1/3 of) the bearing is submerged . Perhaps they meant 'while the engine is running' ? That too is confusing because Pedro's video simulation shows oil being spun out of the bearing as soon as the engine is spinning.I'm not saying Pedro's video is an accurate representation of what really happens to the oil around the IMSB, just that it is interesting and nobody has done any more convincing video of the issue yet?
Porsche IMS Bearing Story featuring the Direct Oil Feed (DO) - YouTube
You are correct ,I too recall some big names saying( the lower 1/3 of) the bearing is submerged . Perhaps they meant 'while the engine is running' ? That too is confusing because Pedro's video simulation shows oil being spun out of the bearing as soon as the engine is spinning.I'm not saying Pedro's video is an accurate representation of what really happens to the oil around the IMSB, just that it is interesting and nobody has done any more convincing video of the issue yet?
Porsche IMS Bearing Story featuring the Direct Oil Feed (DO) - YouTube
02-23-2016, 10:16 PM
#430
Former Vendor
"Convincing video"
Hell, we can't make a video.. If we do we are considered "fear mongers", or accused of making this whole issue up.
To be a true resource, something should not be "convincing". It should be filled with fact, and have years of first hand experience behind it.
It's hard to help people today. So hard that it's not worth it.
Hell, we can't make a video.. If we do we are considered "fear mongers", or accused of making this whole issue up.
To be a true resource, something should not be "convincing". It should be filled with fact, and have years of first hand experience behind it.
It's hard to help people today. So hard that it's not worth it.
02-24-2016, 05:15 PM
#431
Racer
These >convincing videos> show the simple centrifugal forces at play which I'm sure is a contributing factor to some or all failures, but barring impurities/imperfections during bearing manufacture which contribute to few failures, it still does not explain why some bearings fail while others live a long life within the same M96 design and subjected to the same forces at play.
02-24-2016, 05:24 PM
#432
Former Vendor
These >convincing videos> show the simple centrifugal forces at play which I'm sure is a contributing factor to some or all failures, but barring impurities/imperfections during bearing manufacture which contribute to few failures, it still does not explain why some bearings fail while others live a long life within the same M96 design and subjected to the same forces at play.
An open IMS bearing only requires 1cc of oil per minute, you can spin the shaft 20,000 RPM and let it sling oil to Mars, and it'll still retain 1cc of oil per minute.
Of course, some guy thats working out of his garage, developing products with a shop vac doesn't know that.
02-24-2016, 05:31 PM
#433
Race Director
I think it would be great to have a beer with Pedro. Some of his test rigs are...dubious, but on the put-up or shut-up continuum, he's way out near the far end of put-up...
02-24-2016, 05:43 PM
#434
Former Vendor
During lunch at my hands- on classes we play those videos. The laughter from the room filled with seasoned technicians can be heard 1/4 mile away.
The instructors don't even stay in the room.. I turn on the youtube channel and walk out, then ago eat my lunch in the other presentation room while we listen to the roars of laughter that fill the building..
The instructors don't even stay in the room.. I turn on the youtube channel and walk out, then ago eat my lunch in the other presentation room while we listen to the roars of laughter that fill the building..
02-24-2016, 05:49 PM
#435
Racer
Agree Schnell!
The bearing centrifugal forces take place in much, much more confined area than his plastic container so I'm sure quite a bit more oil get back to the bearing area by splashing back from various closed in parts.
Interesting comment you make Jake!
Would some engines' IM shafts and bearings be installed misaligned at the factory by any chance ... due to minute manufacturing imperfections?
The bearing centrifugal forces take place in much, much more confined area than his plastic container so I'm sure quite a bit more oil get back to the bearing area by splashing back from various closed in parts.
Interesting comment you make Jake!
Would some engines' IM shafts and bearings be installed misaligned at the factory by any chance ... due to minute manufacturing imperfections?