OS Lower unit maintenance

[fidelity101]

I took my TS3 (equipped with an OS lower unit powered by a reclaimed Traxxas Spartan motor) out for a run today. It was the first run and it was a blast out of the gate! I'm pretty sure this boat can do standing backflips on 4S. :)

My question is, how do you maintain the OS lower unit after a typical day of running? Under the advice of the original TS3 owner, I picked up some 20w motor oil and mixed it 50/50 with some 80w gear oil and I use that mixture inside a steel can to inject 1 or 2 pumps of oil after each use...pretty easy stuff. The problem I discovered upon returning home and trying to clean everything out is that the OS lower unit was full of water. As soon as I removed the line plugging the oil injection hole, water came out for a few seconds and it was almost 100% water. I let it drain out and shot 2 pumps of oil into the lower fitting until I could see it come out near the drive dog...all good right? Then I shot 5 pumps of oil into the fitting just below the motor until I discovered water shooting out of the top of the Spartan motor. I figure the water is coming out because the oil is forcing it out...which means the motor is now full of oil as well. Which leads me to start this thread on OSE and ask for help! What should I be doing differently and how do most people maintain their OS lower units after a days run.20150922_200107.jpg

[tlandauer]

After a day's run I always :
Take the motor down from the conversion plate, pull the flex cable out and lube it like any other boat with grease then with mobil1 10w-30.
While at the lake between runs I have the mixture similar to yours and I pump it down thru the oil fittings on the unit.
I use the red label CorrosionX and shoot that into the motor's openings, got to dispel any water that is INSIDE the motor, I also use bearing oil to lube both bearings.
I happen to enjoy this routine, so it wasn't a big deal for me----at least not before I discovered flying quad copters.....
But seriously there is so much water in the unit that for me I have to take the side cover down and clean it, the only thing I didn't do is disassemble the prop drive dog part, I figured with the amount of Corrosion X I spray, it should be OK.

[fidelity101]

Thank you.

The motor I'm using is the Castle 1420-1800kv.

So after reading your advise, I went back to the shop and did the following:

I removed the motor from the OS lower unit, pulled the adapter plate from the motor and then soaked the inside of the motor with some LPS-2 (Heavy duty lubricant) into each of the 6 screw holes until nothing but LPS was coming out. I had to remove the motor AND motor plate because the motor plate blocks the 6 screw holes on the motor itself. I then coated the flex cable with corrosionX followed by a large amount of grease to pack the hole before reinserting the flex cable. I had to let the motor sit for a few minutes until the LPS-2 stopped oozing out of the motor before I reinstalled everything.

Also, I noticed that most of the oil (20w mixed with 80w) I insert via the fittings starts oozing out the bottom of the OS lower unit within 5-10 minutes. So while that's a good idea to do at the Lake between runs, doing that at home just leaves me with a big mess the next morning. I'm curious as to why there is so much water INSIDE the OS lower unit. It must be finding it's way in from somewhere and displacing any oil/grease. This makes re-lubricating a vital part of the per run routine else I'm sure the flex shaft would fail quickly.

If I could find a way to seal the motor and prevent water from getting into it in the first place then I could probably just press grease into the lower unit fittings after each run, correct? If that's even possible?

Anyway, this isn't a time consuming process as it only takes about 15-20 minutes but it does make a pretty decent mess in the shop. :) I'm sure I will get better as it with practice but I'd really like to find a way to cut down a few steps if possible...like finding a way to seal up the motor to prevent water from getting in there in the first place. :)

Flying quads is definitely a cleaner (and easier) clean up process. :) Throw them in the back of your car and they're ready for the next run. Unless of course you hit a metal beam at full throttle like I did last week...then it takes a few minutes to fix them up. :) FPV quad racing a blast!

[fidelity101]

This was the first run for the TS3. Apologies for the radio noises and poor video camera skills...it's hard driving and filming at the same time. :)

https://www.youtube.com/watch?v=WxGmbGbRTOw

[tlandauer]

Agreed! I still love boats but the near 100 degree heat here really puts me off to go to the lake. It is a first class venue for racing and the Annual SAW is fantastic. But sometimes I yearn for a lake in a natural setting. For that I will have to drive further and the 24/7 grid locked traffic is enough to drive me crazy, lol... I can fly near an elementary school after hours when no one is on the play ground and it is only 2 min. driving from my home.
I really don't know if there is a 100% way to seal water from entering the motor, I just kind of accepted that is the way with these Out Board drive set ups.
It does leave a rather messy work area after all the necessary maintenance work is done. Do you use teflon tube in your O.S. unit or you have a curved brass tube up grade? Either way, I suppose if you are going to run the very next day, you can get away with NOT having to disassemble the unit. I think water enters from the side cover, although it is not sealed and therefore it would not "hold" water once the unit is out of water. But the inside recessed areas can retain water even if not much.
As with many set ups, the grease is replaced by a mixture with water and I think that's ok during the day's run, this mixture is still slippery and some have said that water is the best lubricant---up to a point before corrosion starts, IMO.

[tlandauer]

This was the first run for the TS3. Apologies for the radio noises and poor video camera skills...it's hard driving and filming at the same time. :)

https://www.youtube.com/watch?v=WxGmbGbRTOw

That looks great! I love Tunnels. I built one two years ago, now you just reminded me, lol....
Radio voice reminder is great! I got to like it after I got a DX6 tx for my quads.

[fidelity101]

I took the FrSky Taranis radio and turned it into a 2 stick surface radio simply by adding hot glue to the gimbals so the throttle only goes up/down and the other stick only goes side/side. I also tightened up the spring tension and backed out one screw which allowed the throttle stick to return to center when released. It's now a very cheap surface radio with amazing range and LOTS of telemetry options. :) 150A sensor, rpm sensors, temp sensor, voltage, gps, etc.

Thanks for the comments on the video, I honestly didn't expect it to be that fast out of the gate. At full throttle, the hull is barely in the water and it corners very well with reduced throttle. I still need to experiment with CG locations as the CG is located at about 7.75" from the transom and that requires a pretty light 4S 4000mah 25c battery pack.

Regarding the teflon liner ...I had to remove the side cover to answer your question as I'd never taken it apart before. There is a teflon liner inside. I packed the casing with some grease and tightened everything down again. I'm using some blue locktite to hold the screw in place, but I'm guess that's going to do nothing with all the oil and grease everywhere. Do you know anything about the copper liner "update"? Benefits?

100F plus weather sounds extremely hot! Buffalo, NY rarely gets above the mid 90's and even that's rare. On the flip side, you'll have nice weather in the winter while I'll be spending 6 months digging my way out of a snow storm. :)

[tlandauer]

Wow, I didn't realize you had converted a Taranis radio to a surface radio . man, that's trick, I wouldn't know what to do. I now realize how many people prefer that radio, but I am new to all this and since my first "hobby grade RTF" is a Blade 200QX, I got a DX6 so I will be there for a while before I move up to the FRSky. At first i thought it was a typo , I only knew FlySly, didn't know this brand, and being from China, I thought to myself "man, us Asians really can't speak between "R" and "L"! They should hire better people to write their website literature",
That is great that you get all the telemetry stuff..... the modification to the gimbals sound very complicated to me, oh well.
As for the liners;
I don't know the characteristics of the teflon liner in this unit, I have three units and they all have been fitted with a brass liner. I think the O.S. is so well designed that the teflon actually works. I have heard that in the ProBoat's Stiletto OB it makes a very big difference.
So if it ain't broke, don't fix it... lol