The International Cessna^® 170 Association

I have been trying to track down an oil leak on the lower half of my accessory case. In the process of tightening everything I can, I found the nuts on the tach cable housing were loose. I was surprised to see that they were nylon locking nuts - didn't expect to see them on the engine. I checked the Continental parts book and was even more surprised to see that it did indeed call for that type of nut.

I removed the old nuts and found that the nylon inserts were trashed and replaced them with all metal self locking nuts.

This may be something to check next time you are nosing around the back of your engine.

Bruce

Mine has regular steel nuts with lock washers.

When I had my gen/failure fiasco with Ron's Aircraft at North Las Vegas airport... Ron himself tried to tell me that the nylock nuts on my generator were "illegal" and should be replaced with plain nuts/lock-washers.

I suggested he consult the TCM and Cessna manuals and to install the fastener specified. (It was the fiberlock/nylock nuts already installed.)

The accy case is not a particularly high-temp area and nylock nuts perform fine in that function,. It's what serves just fine on my airplane, but I cannot find any reason that all-metal locknuts wouldn't be superior replacements, (although they probably place more stress and wear upon the stud's threads.)