Changing the oil level gage tube (dipstick tube)

On my IO-360-A1B6, the plastic Lycoming oil level gage tube (75736) is always coming loose, and now both of the available safety wire ears are broken. So I decided to replace it with the metal Superior tube, SL75767. The Superior tube is 1" shorter, so I expected to have to cut and remark the dipstick.

Surprise! The thread at the top of the SL75767 is larger in diameter than the the 75736 and the existing Lycoming dipstick won't thread in.

Has anyone else done this and used the Superior dipstick (oil level gage assy) SL14780? I would like to confirm that it

[1] has the correct thread for the SL75767 tube, and
[2] is long enough to mark for the IO-360-A1B6

Other options might be, if anyone knows the threads for both the SL75767 top end and the Lycoming dipstick, to make up an adapter.

Thanks,
Andy Elliott

Superior SL75767

No one came up with any help on this one, so I worked it out the old-fashioned way. Here is a pic of the Superior metal dipstick tube, SL75767. It is quite a nice piece. It is drilled for safety wire at the bottom on two sides, and I don't think the wire will pull out of this!



The lower threads (where it enters the case) are the same as the Lycoming plastic tube, UNF 1.125-12, and it uses the same gasket. The upper threads are not the same. The Superior tube is threaded UNF 1.250-12 and includes a ledge for an o-ring at the bottom of the threads. The tube is 10.57" long. So I used a 3D printer to make up a custom cap for it.



This cap is APLA, and I'm not sure it will do well in that location, so I'll probably need to make another from a higher-temp plastic. Regardless, I'll need to carefully measure the markings on the existing dipstick and match them depth-wise on the 1/4" aluminum rod that will get marked and JB Weld'ed into the cap. The assembly looks like this:



I expect to get it installed this weekend, and will advise how it works.
Andy

Another method of safety wiring something that doesn't have a "hole" is to put a worm-gear clamp around the object and safety wire around the screw head.
This is how I safety wire Rotax oil filters.

I had the same problem - went to the 75767 because the 735 was too short and found my cap didn't fit - 1/8" too small. I posted here but got no answers.

I don't have a 3D printer, but I have a lathe, so that's how I will be dealing with it. Beats paying $100 for a new dipstick which is essentially 35 cents worth of plastic and an aluminum or stainless rod.