Timeing gear Idler

[The Jug]

I'm getting ready to put this motor together for my JD 350 ill just call it 3152 when i noticed part # 10 B under front cover (screw that holds idler gear on) is a little under weather. When i took it apart it was totally loose and on the way to a catastrophic failer, I believe i got to it just in time.
I looked up part number 10A and 10 B both screws were not threaded to top. But then when i took a look at the idler shaft part # 3B R109863 this makes sense for this is also no threads in the respective area. Now here is what I'm not sure of. The Idler shaft i have is threaded so i looked at the sub T26323 which is threaded and R 89824 also threaded. What would be the proper screw for the threaded shaft, or should i get the non-threaded shaft and new screw to match? i hope this doesn't seem like off the wall question and i was clear in describing this. I'm just not sure why this screw was loose. Was it improper parts or improper Tork on screw? If i know the correct parts to use I'm sure i can get the other part correct and should lead to no more loose screw. Last but not least if i use the parts i have but make sure Tork is proper would this do the job?

[Jim B]

What exactly is wrong with the parts that were in it, besides the screw was loose?

If the threads on the screw are bad get a new screw from JD. You can clean/degrease the internal threads and the screw's thread and put a bit of blue thread locker on it, then properly torque it.

It appears all the shafts sub to R109863 in the end. If you decide to change your current one, get that one and get all the parts that go with it.

[The Jug]

The idler shaft is threaded all the way out. The bolt that was in there is not threaded all the way i guess like a carriage bolt you could say. It seems some of the idler shafts are not threaded. so i guess what i am trying to find out if i have the incorrect bolt or incorrect shaft.

[Jim B]

Sorry, I'm not being much help here. Not having the parts in hand or being able to see it is a disadvantage.

The shaft with no threads would say the bolt passes through the unthreaded hole and threads into the block or a nut behind the shaft, clamping the shaft in place.

Having internal threads would say it has a fastener that threads into it to pull it tight to a plate, like a nut on the end of a bolt; UNLESS the threaded hole is larger than the bolt diameter and the bolt just passes through the hole with no thread engagement.

I did a part number search and found that T26323 shaft used in some other engines and it appears to me the threads do not engage the bolt, thus the sub to an unthreaded shaft R109863 and a self locking bolt, T26327.

[The Jug]

Right my bad for not figuring out how to post pictures for sure would help for times like these. I'm not trying to put machine back like museum quality just trying to build solid machine. I do appreciate any help and input i can get. You have answered lots of questions that would make some think why am i even working on these machines. But i know the only stupid questions is usually the one never asked. I'm a master in the electrical field and still learn every day. working on these is just a hobby for my camp in central Maine. I think your right ill just use the locking bolt and the threaded shaft that passes through shaft (even know that it has threads but doesn't make contact). Ill replace the thrust washer for it has slop in it and use blue lock tight to make sure it won't come loose again. Call it a day and move forward. the oil slinger will be replaced also. everything else looks good so far.

[Jim B]

I am thinking the bolt passes through the internal threads of the idler shaft without engaging them, thus threads or no thread inside the shaft doesn't matter. It would appear the shaft gets tightened against the block or front plate; the shaft has a roll pin in it to keep it from turning. That idler shaft may have been used in another application where a larger bolt engaged the shaft threads to tighten and hold it in place, making the idler shaft act like a nut on the bolt.

Keep plugging away at it.