Another noisy gear box or clutch issue

[loueelotus]

Hi All,
I have an issue that has started and I need to figure out the cause of a problem that has started this summer while driving the Lotus Elan S2.
First a little history. I replaced the slave cylinder about 1/1/2 years ago with the one from Lotus ReMarque which is made of billet aluminum... beautiful piece, but it was a bit loose and was told that?s OK.... Anyways, last winter I changed the oil pan while the engine was in the car. WOW!! What a job but it got done fairly well. I had to lift the engine as high as possible to replace the oil pan and was wondering if that is the cause of the issue which l will explain.
At the beginning of the spring May 2016 I took my baby Lotus Elan S2 out and shortly after a couple weeks I heard a sound coming (from gear box??) when I released the clutch pedal in gear. First it was in a couple of gears then progressed to all gear as the summer continued.. Then I noticed that it started when in gear traveling at about 60 mph (in 4th gear) and it was getting louder as the days passed and is on 2nd and 3rd gear now too. The sound is like a very slight grinding (it sound like a "ching'' just for a second) It seems to happen when accelerating or decelerating now but not all the time. Now this week I noticed it started in neutral too but it very low sounding now. I will be pulling the engine and transmission next year if I need to, but would like to drive it one more summer. Can anyone give me a reason for this sound.. The car runs perfectly.. No issues.. Could it be adjustment on the slave cylinder which I will check when the car is put away, or release bearing, pilot bearing, the fork, or main gear shaft? Or whatever you think it is..
Your input would be very much appreciated,

Regards,
Lou

[gearbox]

Have you tried shortening the clutch slave rod and checking the return spring? It may be just the throw out bearing not completely disengaging from the pressure plate when the clutch is released. Hard to diagonose a sound but I would check all the easy stuff first. Good luck, Allan

[Elan45]

As scarce as gearbox bits are today, I wouldn't take too many chances w/ a grinding noise.

From the little info you've provided, my 1st guess would be the pilot bearing inside the input shaft, 2nd guess would be perhaps the input shaft bearing coming loose on the input shaft, allowing it to move axially. Neither a good situation. I'd want to know what was making the noise.

Roger