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! |
Cracker |
Oct 21 2017, 08:57 PM
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#2
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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 |
Update
Well...it doesn't look good. I checked power at the fuse panel and have ignition, fuel and spark - Hell, I got power everything. The engine started up and then died within seconds; a second attempt led to the engine dying even more quickly. After the third start (again having difficulty turning over but catches) it made a strange noise as it shut down - a rotational scraping type noise. I did not hear it the two times it ran. At this point, unfortunately, I believe my original assessment at the track may unfortunately be true - something is likely wrong on the bottom end. Oh well. One interesting observation: When the ecu primes the high pressure fuel pump the gauge will "hold" that pressure for startup; however, right now that pressure is dropping immediately after the pump cycles off. Hmm? I plan on getting the car up on the stands tomorrow afternoon and pull the pan - I'll be looking for bits and pieces that shouldn't belong. If I have anything that warrants pictures I'll share the gory details. Tony |
DM_2000 |
Oct 22 2017, 06:31 AM
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#3
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Member Group: Members Posts: 217 Joined: 16-August 17 From: PA Member No.: 21,351 Region Association: None |
Update One interesting observation: When the ecu primes the high pressure fuel pump the gauge will "hold" that pressure for startup; however, right now that pressure is dropping immediately after the pump cycles off. Hmm? Before you pull the pan, pull the spark plugs and bar the motor over. For an engine to stall due to friction, you will barely be able to turn it by hand. With this drop in static fuel pressure, you might have hydro locked a cylinder due to a leaking injector / manifold referenced fuel pressure regulator. This is a bit of a stretch given you didn't note any fuel smell / rich exhaust when it was running. Given the battery voltage was so low on track , the starter may have stayed engaged while the engine was running. This would have out run alternator output discharging the battery. A failed lower end won't directly cause the battery to discharge. Is the fan belt still driving the alternator? |
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