Lockup Surge in Allison 1000s

这是一个案例。2001年2WD雪佛兰1500带6.6L柴油发动机和Allison 1000transmissionwas returned to a transmission shop. The transmission had been overhauled recently and the customer’s complaint was a cycling TCC, or what he described as a lockup surge. A scan check of the vehicle found no codes. The PCM would command the TCC solenoid off at regular intervals. The vehicle’s tachometer remained steady, but the live data on the scan tool showed a small repeating spike in the engine rpm. The pickup for the engine rpm sensor is the input speed sensor located in the bell housing of the transmission and is excited by the row of dimples on the torque converter closest to the engine.

It turned out that one of the dimples在转换器的外面was partially flattened by a handling mishap and was causing the rpm glitch. Replacing the converter fixed the problem.

在类似的事件中，2001年雪佛兰2500HD拾音器返回到具有相同锁定浪涌投诉的传输商店。再次，没有代码。PCM将命令PWM电磁阀升降至约60％，然后将TCC电磁阀关闭。然后它会重复循环。发动机RPM的电影快照显示了一个均匀间隔的150 rpm峰值。在这辆车上，发动机RPM毛刺是由排水塞引起的，即转换器Rebuilder在激励器凹槽行中的两个凹坑之间添加。

在另一辆车中报道了一个锁定浪涌。在这种情况下，浪涌不像其他两个那样频繁或发音。没有代码存在，锁定问题最初被诊断为发动机未命中。当发动机RPM的电影显示故障时，终于找到了问题。这次故障是由两个小型平衡重量引起的，这些重量被添加到盖子上，它遇到叶轮。

bob游戏怎么下载变矩器rebuilders将不得不修改their handling practices with the Allison 1000 cores. Small imperfections in the dimples that excite the speed sensors may now require removing the converter. Impeller run-out will also have to be monitored more closely. Most rpm sensors have working clearances in the .030” range.

We have all seen the small creases that can be found on many impellers. These creases originate when the plate steel passes over rollers on its way to becoming a roll of steel. Until recently these small creases had no negative effects on the functioning of a torque converter. But now, even these small creases cannot be tolerated on Allison 1000 converters.

There have also been some concerns about the interchangeability of the early vs. the late converters. The early-model converters were manufactured by the Aisin Corp. and the late models are being manufactured by LuL. There are some small dimensional differences in the dimples on these converters. The dimples on the early converters are .835” tall and the dimples on the late models are only .765” tall. The height difference on the dimples should not pose a problem because the diameters of the converters when measured at the dimples are the same. There is also a small difference in the angle of the dimples. This should not be a problem either, since the dimples are the same width and the area that the speed sensor passes over is the same on both. Both converters have 31 dimples and the input (engine) speed sensor (p/n 29536408) has been in use since May 2000.