The Build · NCM series, part 2 of 3 · Race wrap-up
Black Flag Racing went to Bowling Green to find out what a summer in storage had done to the #86, and the car answered in full: an Accusump line, twice; a thermostat housing; a fan switch; the ignition wiring the fan switch was hiding behind; the radios; and, at seven o’clock on Sunday morning, a head gasket. Sixty-one laps, all on Saturday, all in a heat advisory, all by one driver, and every one of them made possible by two people who had never worked a pit wall before Thursday and ran ours like they’d been born on it.
A shakedown race is where you go to find out what’s wrong. By that standard, The Colonel & The Sinkhole was a complete success, and we would like it noted that we said so before the invoice from the engine shop arrived.
The scoreboard
The official result reads 85th overall of 97 entries, 29th of 30 in Class C, 61 laps, 192 miles, best lap 3:05.215. Read cold, that’s a bad day. Read with the lap chart open (part three of this series has all of it), it’s a car that ran quicker every stint it was on track, gained places every time it circulated, matched its own simulation to a fifth of a second, and then spent three hours of Saturday stationary and all of Sunday on jack stands. Seventeen teams didn’t turn a lap on Sunday either. We just had the most colorful reason.
Some context on the thermometer, because it was the other competitor that weekend. Saturday went green at 86°F and reached 97 by three in the afternoon, with the heat index between 97 and 99 and a Heat Advisory posted until seven that night. The forecast had called for 97. The forecast, unlike several of our hoses, delivered. One driver ran every lap of it. By plan, he recovered only in the paddock, never at a fuel stop, and climbed back in every time with a CamelBak full of ice and electrolytes pressed into his hands by a crew that had read the manual and then improved on it.
Two people, one wall, seven and a half hours
Here is the part that doesn’t show up on SpeedHive. Black Flag Racing brought three people to Kentucky. One of them drove. The other two, the newest members of the team, welcomed in the One Month Out article with a line about how glad we were to have them, did everything else. Everything else turned out to be most of the weekend.
They ran all four stops, including the fuel stop, where eleven gallons went in by gravity from two jugs, one person over the wall and one on it, exactly the way it was rehearsed in a driveway in Nokesville three weeks earlier. When the driver came in on lap 24 with the oil pressure falling, they found the split Accusump line, reworked it in the paddock, chased down a loose connection that briefly kept the car from leaving, and had it back on track in twenty-eight minutes, in 91°F, on a car they were still learning their way around. When it came in again on lap 44 with the same line loose and the temperature gauge heading somewhere new on the crawl back to the paddock, they did the two-hour repair in the full afternoon sun: line reattached, a thermostat housing found leaking and fixed, a dead fan switch diagnosed, the car sent back out at 3:35 to run fifteen more laps. When the car went dark on Saturday night, they were under the dash with a multimeter. On Sunday morning they read the dipstick, called it correctly, and loaded a race car that wasn’t going to race.
And the radios. Part one promised that the no-radio rehearsal would turn out to be the best hour we spent all summer, and here’s why: the Baofengs were unreliable all day, a swap at the fuel stop didn’t change their mind, and by early afternoon the team’s entire communications system was a pit board, two arms, and a driver willing to read at sixty miles an hour. It worked, because the crew had drilled it and because a pit board is honest in a way a radio never is. If it says FUEL, the driver comes in, and nobody has to ask anyone to repeat that. They picked up the board when the radios quit and never missed a call for the rest of the day.
We gave them a printed procedure and a rehearsal. They gave us a pit crew. There is an old rule in endurance racing that the driver gets the trophy and the crew gets the T-shirt. We didn’t win a trophy. The shirts are being ordered anyway, and everyone who sees them will assume that’s a race we finished, because in every way that matters to this team, we did.
What broke, in order
For the next team that reads this before their own shakedown, here is the chain. The details live in part three; this is the shape of it.
Two things to say about that list. First, the transmission. In part one we told you welding wasn’t an option and epoxy was, and that everyone nodded and nobody felt good. It did not leak. Not a drop, not on Friday, not through a race day that cooked everything else on the car. We have stopped mentioning this out loud in the shop in case the transmission hears us and gets ideas.
Second, the ignition. In part one we also mentioned that with the factory ignition and immobilizer gone, Honda no longer had a vote on whether the car starts, and promised that sentence would get funnier. Here’s the punchline. During a pit stop we noticed the electric-fan switch was dead, so the cover came off the switch box to get at it, and taking the cover off broke the connection to the ignition. The car went dark. The first theory was the battery, which is always the first theory, because batteries can’t defend themselves. The actual theory is that on this car nothing is allowed to fail alone. The fan switch brought a friend.
Sunday, 7 a.m.
The pre-race inspection is a checklist we run before every green flag, and on Sunday it got as far as the dipstick. The oil was frothy and the color of a milkshake, specifically a purple one, because Saturday night’s oil change had gone in with Royal Purple and the radiator had been topped off before anybody knew the two systems had started sharing. Combustion pressure was in the cooling system. When the radiator cap was loosened, the cap confirmed it enthusiastically, leaving the radiator at speed and in a direction we haven't been able to reconstruct.
One radiator cap, Honda, last seen departing the paddock at NCM Motorsports Park vertically. Answers to “cap.” Reward: one Black Flag Racing team patch and our sincere respect.
That’s the picture of a failed head gasket, and it’s our working diagnosis until the head comes off. The engine turns over. It doesn’t start. In Lemons those are two different sentences, and the first one is the one you want, because a K24 that turns over is a K24 with a future. It rode home to Virginia on the trailer and is now at Haas Auto Service Center in Manassas, where it will get a head gasket and a proper look inside, and where, for the first time in this car’s life, a repair will be performed by people who are not also trying to write a blog post about it.
Whether the pit-lane thermal event took out the gasket or the gasket caused the thermal event is a question for the teardown. What we do know is that the whole chain starts at one hose, and that the driver caught every oil-pressure drop from the seat and brought the car in every time. That reflex is why there is a head gasket to replace and not a block to recycle.
What the shakedown shook out
This is the accounting we came for, and the list of things that passed is longer than the list of things that failed.
Passed: the TSX brakes, bedded during the race and never faded; the Kendas, scrubbed in under green; the KTuner tune, finished in the first hour in traffic and good enough to put the car within two per cent of its simulation by the fourth stint; the fuel model, right to the gallon; the heat plan, which kept a solo driver flat through a 96°F stint; the push-button start, the quick-release wheel, and the printed dash; the epoxy; and the driver, who drove to the limit of the car rather than his own and brought it home three times when the gauges said to.
Failed: one Accusump line, three times; one fan switch; one ignition junction that shouldn’t have shared a box with it; one thermostat housing; the radios, for the third race running; and a head gasket, the only item on this list we’d have paid real money not to find.
Now look at the calendar. Summit Point is October 24 and 25. Houston is after that. Every item on the failed list is now a known, specific job with a date on it, instead of a surprise waiting in a corner of West Virginia. That’s the entire argument for a shakedown race, and Bowling Green made it for us in one day.
Next moves: Summit Point
- Head gasket at Haas, with a full look inside. Bores, bearings, and an honest answer about what three oil-loss events left behind. Nothing else on this list matters if the answer is bad.
- The Accusump plumbing gets solved on a bench or the Accusump comes off. Three failures of one line in a day is a routing, heat, or fitting problem. Either the fix is bulletproof or the baffled pan runs full and the safety device stops being the risk.
- Cooling system pressure-tested; fans and ignition rewired. The fans get a switch and wiring that survive a race weekend, in a box the ignition doesn’t share.
- An oil-pressure warning light on the dash, and a standing order. Under the red line means box this lap. The driver did it right three times; a light makes it automatic.
- Radios that work, tested at distance, before we leave the driveway. Antenna, headset, mount. The pit board stays in the trailer as the backup it proved to be, not as the plan.
- The crew of two becomes the core of the crew. They’ve done the hard version now. Summit Point gets the same two people, the same laminated procedures, and a car that owes them a quieter weekend.
- Plan the cold start. Carolina taught us what a cold, damp first hour costs. Bowling Green never got below 86°F, so that lesson is still waiting for us in October.
The #86 went to Kentucky to find out what it had forgotten over the summer. It told us, in order, with a missing radiator cap for emphasis. Now we know. Thank you to the two people who ran our pit, to the driver who ran our car, and to everyone who waved at the Accord as it made its way, slowly and purposefully, back to the paddock one more time.
Shakedown complete. Summit Point, you’re next. All the Way.
