Engine Failure at speed... |
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Engine Failure at speed... |
Cracker |
Oct 15 2017, 08:14 PM
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#1
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Advanced Member Group: Members Posts: 2,148 Joined: 2-February 10 From: Atlanta (area) Member No.: 11,316 Region Association: South East States |
Well, it is not "if an issue will occur on a race track" but rather just a matter of when! Sunday morning was gorgeous at roughly 65 degrees and cloud cover. The grip was surprisingly good and the dense, cool-ish air enabled the engine to run really strong.
The night before, a few of us "walked the track", taking in the nuances that really can only be seen on foot, kneeling down and taking our time. More drivers should take advantage of this to become more familiar with details that are completely missed behind the wheel of a car. Anywho... We were discussing an asphalt patch that is on entry into the downhill section to turn 10a...specifically, how the patch had an elevated center with ramps on either side. A friend mentioned, "hitting that at speed would cause quite the jolt to the car and driver". Also of concern was the potential loss of grip and the unsettling of the chassis at such a critical point. He was correct as I bore out witness the next morning. We have still not found the smoking gun and only hope it is not internal; the top-end is fully functional with each of the valves operation correctly. The engine does not turn over quickly and that obviously is a cause of rather great concern. I have been doing track events for some time now, over 15-years, and have never encountered such a failure. I guess I can say...enjoy the failure at my expense. PS: Talk about cutting it close...lose an engine down the hill; try to jump start the engine at turn 10a and just BARELY make it up the hill over T11 to glide back to the hot pits. Whew - that was close! (IMG:style_emoticons/default/biggrin.gif) Cheers! Tony https://www.youtube.com/watch?v=VRvMJeXJxTQ My son came in from college - great memories at the track with him! |
DM_2000 |
Oct 27 2017, 06:41 PM
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#2
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Member Group: Members Posts: 217 Joined: 16-August 17 From: PA Member No.: 21,351 Region Association: None |
As for the in car crank change, too much metal goes through the oiling system when a bearing burns down to make this a sake bet. ( Even if engine is out of car but not fully disassembled to clean oiling passages. ) I have changed many cranks in road cars but that was due to long term wear rather than a metal dump.
If a bearing actually spun, the bore will be damaged. Bore roundness is critical as that is what makes the bearing round not the bearing insert. Also, bearing tabs are there to laterally locate the bearing not to keep it from spinning, radial tension does that. When oil clearance gets too large, the crank journal hammers the bearing thin and the resulting loss of radial tension is what allows the bearing to spin and damage the bore. |
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