Oil tank shield

[4004]

I've used TITESEAL for those occasions for many, many years - excellent sealant also. One of my mentors put me on to it 65 years ago.

[a64pilot]

It is not part of any kit, pn 0450166. Interestingly, it is not required on 140's after sn 14305, but is on all lower serial numbers, and on all 120's regardless of serial number. I believe this coincides with the change to the C90 in the 140.

Didn’t the aircraft with the C-90 have a lip that was added to the lower cowl to increase the negative pressure in the cowl to improve cooling?
If so then it may not be needed.

[6643]

Didn’t the aircraft with the C-90 have a lip that was added to the lower cowl to increase the negative pressure in the cowl to improve cooling?
If so then it may not be needed.

Yes, but they call it a "doubler". It's required if you convert an earlier plane to a C90, also. Not sure if it increases negative pressure, but that all makes sense.

I have a C90, a true doubler (not a lip), and the oil tank baffle. If anything, it runs too cool.

[7981]

My C-120 was missing the sump baffle and oil screen blast tube. Made a new blast tube. HUGE differance in oil temp. Baffle not available that I can find so I am going to make one from soft Aluminum sheet and heat treat it. Have not seen any official approval to run without it.

[a64pilot]

Why heat treat? it’s under no stress and isn’t load bearing.
Then how are you going to heat treat? At work if memory serves first we soaked the parts in a molten salt bath for an hour or so, then took them out and very quickly quenched them in water, if we wanted to delay the heat treat, they went into the freezer, if not then it took a few days at room temp to harden.
It’s the heating up to almost 1000f that’s going to be tough to do, and holding that temp for an hour, and I believe it has to be an even temp, hence the molten salt solution and not an oven.

Unless you have the facilities, I’m not sure you can do it.

[tonycondon]

I just changed the gasket on the oil tank in my 120. This thread was very helpful so I knew what to expect. Went ahead and put on the MS20142-4 locking nuts instead of castellated. The shield was a pain to remove but easier to put back. We loosened up the carb heat cable to help.

Went with the ~$8 silicone seal from Aircraft Spruce. 15 in-lbs. Used a small torque wrench with a crows foot. found the running torque of the lock nuts and added 15 and converted for the crows foot.