48 state gearbox on a Viking 130.

I can't track down the source of this oil seepage and hoping you all have some other ideas. I figured I'd throw it out here before bugging Jan since I know they're busy plus this might help someone else too.

This isn't a whole lot of oil but this is after a 1/2 hour flight.  There are definitely some drops pooling plus some blown back on the upper parts behind the gearbox.

Things I've done:

 - replaced temp sensor

 - replaced the plug in the spare hole

 - replaced the o ring on the fill hole plug

 - tried to tighten the lug that is top front

 - used loctite 567 high temp thread sealant on the temp sensor and the spare plug

 - tightened both plugs on back of box and overflow port.

 - no oil on lower portion of gearbox or engine

 - no dripping or oil puddles after long sits in the hangar

- I've ziptied tightly rolled paper towel around the base of both the temp sensor and spare plug before flight.  Both were dry on the inside part after the flight yet still oil seepage so 99% sure the oil isn't coming from them.

 - The last thing I tried last night was the new o ring but didn't get to try to wrap it in paper towel to test. It might be hard to zip tie that part.

- I can't see oil seepage while idling on the ground. It might be happening but I just can't get too close due to the prop.

Any ideas?  

Thanks - Jim

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Hey Jim, are you sure it is gear oil and not coolant? -Alissa

Good thought Jan. I’ll look into that as soon as I get back in town later this week.
Thinking about the viscosity during all the times I’ve wiped it clean to try something new, I’m almost positive it’s oil and not coolant.
If I can get back from Chicago on Friday night, I’m planning on going up to Zenith on Saturday.

Thanks - Jim

Update - I met Jan and Alissa at the Zenith Homecoming last weekend.  Jan noticed right away that the brass plug was cross threaded.  We replaced the plug and screwed it in correctly with loctite 567.  

 Unfortunately that didn't fix the problem.  I tried a few more things such as washers and even re-tap just a little but all to no avail.

 Reading on-line - most people recommend a permatex thread sealant and locker.  I applied that yesterday.  The directions say 72 hours for a full cure so it will sit for about a week now until I get back from a work trip.

 I'll update you all next week.

 - Jim

Hey Jim,

got an update on the leak?


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