Not going to happen again!!!

[Lay26]

2yrs ago I suffered a catastrophic drive failure while chasing the season championship. In the last heat of the last race my mono drive wrapped up on itself. It was due to the fact it didn't have enough lube...I probably didn't grease the shaft before that heat and I paid for it. Fast forward this season...my new mono I think I have that problem solved. this drive has three ports for oil...one closest to the motor was thanks to Wally...I saw it in his mono and chased down the pill bottles from win dixie while I was in Florida christmas..I probably cleared out all they had on the shelf that day. What you guys think...did I miss anything?

 

[Wally Duarte]

Looks good - the oil reservoir port will draw the oil to the strut as you’re running. If I’m seeing this right any other hole is going to push the oil out and keep the inside of the hull well lubricated haha

 

[Wally Duarte]

Oh and make sure you drill a small pin hole thru the center of the cap so the container will breathe and release the oil

 

[Lay26]

The second one I was planing on pluging it with the Tygon tubing. It's a port for the grease gun I use. Thanks for the tip as I didn't think of that.

 

[Wasted wages]

Not sure what changed in the last 13-15 years with all of this shaft lubing nonsense....but I think it all causes more problems than it solves.

I run flex shafts, with bushings in the tube at the strut, use blue waterproof wheel bearing grease for lube and run all weekend with no problems....done it this way forever...and I've never wrapped up a cable. EVER.
Hell, I threw in my gas mono this weekend, first time in 15 years I've had a transmitter in my hands.. never even pulled the cable from when I greased it 15 years ago....cranked it up and burned laps...
If it any broke, don't fix it.

 

[Lay26]

Frank you probably used a good grease from the start...that's one of the lessons I learned late with the monos...i ran mostly hydros and they don't need as much cause they're not dragging a lot of surface area through the water....monos do and sometimes I didn't apply grease between heats....I wasn't using a good grease at that time, that's why I think it failed...but it's not happening again!!

 

[Daniel's Racing]

Leighton,
The hydro driveline is not different because of less surface area of boat through the water. The difference is a hydro's driveline goes right through the bottom and it water cooled. You are dragging the Hydro driveline through cool water. The Mono has the drivelive in the boat getting red hot with no cooling at all from the water. If you want a mono drive that works like a hydro you have to water cool the stuffing tube. Night and day difference in driveline longevity. Then some of the drives for monos are setup wrong and the stuffing tube doesn't go all the way through to keep the lube in the driveline and it also doesn't all make it to the bushing that way and you lose it all out of the stuffing tube because it isn't captured.

You usually would only want to feed oil lubricant in the front. The windings in the cable are extremely effective at moving it from front to rear. The rear is usually the last section to be starved.

Not a lot of benefit to feeding in the back as it could actually have enough force to push back up out of the rear fitting.

I guess maybe that is better than losing it going out the bushing in the back and it can go back to tank to go back in the front. Recirculating system. Lol. As long as enough still gets back to the drive and I think it would. Not going to be a problem but may not help much either since the cable already is moving lube rearward with some force.

Watercooled mono drive,

 

[K F Wheeler]

FYI, twenty years ago, I use to use a fairly thin oqua grease. Can't remember who sold it. Technologies Hobbies(?) sells an equivalent.
What I'm wondering is, is there a difference between the Teflon lead bushings that I used in my Sport 40 and B hydro? And the brass bushing that I'm using now. With the lead bushing I would grease every two heats. Tried one time to go a third heat but could hear all kinds of noise in the drive line. Never did that again! With the brass bushing in the end of the strut, the drive cable seems to need re-greasing about every heat! After one heat it looks awfully dry for my liking... Any thoughts? This is on a Sport 40.

Ken

 

[Wasted wages]

I've run sub surface and surface drive mono's for years....tube from motor collet through the strut.

Again, no issues. Never runs hot.
20's through F nitro mono's and gas mono's.

Don't see the need to overcomplicte things..

I will share a secret, just something I do.

YMMV....

Once the new tube has been installed, and the strut is set, I take a cable that I keep just for this purpose, coat it in diamond grit valve grinding compound, and spin it in the tube with my air powered die grinder. Slowly moving it in and out.
It polishes the inside of the tube to a mirror finish...

Is it necessary? Maybe not, but it works for me...

 

[Wasted wages]

More food for thought,,
Typical marine grade grease has a 500 degree F
drop out temp... with a 1400+ deg F 4 ball wear test point,,, with only a 6 % loss rate.

It's my belief that with the entire cable coated with grease, the cable rides on a hydrodynamic wedge of lubricant all the time. Much like the way a main bearing in an engine works...the cable actually never touches the wall of the tubing under normal conditions..

The problem I see with these oil drip systems is, there can never be enough flow of oil to create this shear wedge... think about it, a main bearing in an engine is working under perfect conditions to live...
Polished journal, babbitt main bearing. oil being pumped in at 40 psi to create the hydrodynamic wedge, oil carrying off the heat.. all with several quarts of oil to be recirculated, filtered and reused.

Maybe if the cable had a large oil tank, oil pump, and recirculation system, I'd be impressed...
Otherwise I think the cable is merely surviving under poor application..

Having to cool a shaft log is merely treating a symptom, not curing the problem.

Just my .02..

 

[Daniel's Racing]

Having to cool a shaft log is merely treating a symptom, not curing the problem.

Just my .02..

Yea it is treating a symtom alright. The problem is heavy boats, big powerful engines and huge propellers. You fix that problem you won't be having much fun. Lol.

Do you have a iota of expirience with current high performance twin cylinder inline 61cc powered hulls that weigh close to 30 pounds and run upwards of 80 mph ?

These Inline Superboats are brutal on drivelines. Nothing you have ever run or used to would likely last 1 lap. Welded stub cables it twist them off like toothpicks.

I wasn't really suggesting to watercool your little single gas or nitro boat.

My point was to explain the difference in mono and hydro driveline that changes things considerably. A mono hull runs a driveline totally inside the boat so it gets no water cooling so they run very hot and a hydro has it's driveline under the boat where it is completely watercooled so it runs very cool. Just saying this does have a huge effect on how we need to lubricate the drivelines and why a mono may be harder on shafts than boats with driveline fully submerged.

Then I showed and example of a watercooled driveline in case anyone wondered how that worked.

Watecooling would though be beneficial though to any size mono. Keeping it cool has huge effect on longevity and keeps the lube thick so it doesn't all run out the back like water. No need though when they do not have issues. Why would anyone try to fix something that was working just fine ? Duh. No one suggested doing that. I wasn't really suggesting anyone do anything. If you don't like the idea at all I do not care

The inline superboats do have heating issues in their drivelines and this is the answer. My boat builds won the Superboat class at Winternationals twice and the Superboat shootout twice in last few years. Not one of the heats in any of the races was there a single DNF because of driveline failure. Every single one had a watercooled driveline.

 

[Wasted wages]

Yea it is treating a symtom alright. The problem is heavy boats, big powerful engines and huge propellers. You fix that problem you won't be having much fun. Lol.

Do you have a iota of expirience with current high performance 30.5cc and twin cylinder inline 61cc powered hulls that weigh close to 30 pounds and run upwards of 80 mph ?

These Inline Superboats are brutal on drivelines. Nothing you have ever run or used to would likely last 1 lap. Welded stub cables it twist them off like toothpicks.

I wasn't really suggesting to watercool your little single gas or nitro boat.

My point was to explain the difference in mono and hydro driveline that changes things considerably. A mono hull runs a driveline totally inside the boat so it gets no water cooling so they run very hot and a hydro has it's driveline under the boat where it is completely watercooled so it runs very cool. Just saying this does have a huge effect on how we need to lubricate the drivelines and why a mono may be harder on shafts than boats with driveline fully submerged.

Watecooling would though be beneficial though to any size mono. Keeping it cool has huge effect on longevity and keeps the lube thick so it doesn't all run out the back like water. No need though when they do not have issues.

The inline superboats do have heating issues in their drivelines and this is the answer. My boat builds won the Superboat class at Winternationals twice and the Superboat shootout twice in last few years. Not one of the heats in any of the races was there a single DNF because of driveline failure. Every single one had a watercooled driveline.

30.5 cc in my Rico superboat...1/4" welded stub cable,, brass strut bushings..greased .no issues with cables..

Inline twins, nah, not impressed.. I've seen a few run.. seem to be more trouble than they are worth..
Don't ever plan on running them.

My twins are all nitro baby !!

 

[Daniel's Racing]

If you are not having problems yea certainly wouldn't need to watercool it.

I was not suggesting and I have never water cooled any other driveline or suggested someone do so in anything other than a inline powered Superboat.

Leighton is not new to this. It appears he is still searching for a answer. Maybe I was suggesting maybe he try water cooling next. He is after something more, eh ? Twin oilers and everything.

Again my only point was to demonstrate the difference between a cool driveline under the boat in the water and one completely inside the boat that gets extremely hot.

Mike was noticing the difference in his mono versus his hydro driveline. Was just pointing out a huge difference the two have. That is all.

Inline Superboats were having problems because of the power, weight and size of props used that the drivelines were failing regularly and they benefit greatly from a water cooled driveline.

Surely I would not take the time to do this if it wasn't needed and sure as heck wouldn't continue to take the time with every Superboat build if it wasn't helping.

Night and day difference. The tube stays cool and the lube stays a thick consistency and doesn't all just flow out of the drive. The tubes were getting so hot it was taking the temper out of them and they get soft as heck and sticky wanting to bind up the cable and seize the driveline.

Inlines are a lot of fun. They take some work. Your right they are not for everyone. Too fast and everything about them takes effort to keep it going. With a proper build and maintenance they can be almost as dependable as any boat.



These are funny pics.

Was it horsepower or torque that wrapped that up ?

Talk about heat. Think he lost lubrication. Melted the shaft while in the water.

 

[Bryan haley]

Not sure what changed in the last 13-15 years with all of this shaft lubing nonsense....but I think it all causes more problems than it solves.

I run flex shafts, with bushings in the tube at the strut, use blue waterproof wheel bearing grease for lube and run all weekend with no problems....done it this way forever...and I've never wrapped up a cable. EVER.
Hell, I threw in my gas mono this weekend, first time in 15 years I've had a transmitter in my hands.. never even pulled the cable from when I greased it 15 years ago....cranked it up and burned laps...
If it any broke, don't fix it.

Yup I've been using the blue bel ray waterproof grease I use on my dirt bikes for years never had a issue and after a day running there is still lube on the shafts

 

[Rod Fonda]

More food for thought,,
Typical marine grade grease has a 500 degree F
drop out temp... with a 1400+ deg F 4 ball wear test point,,, with only a 6 % loss rate.

It's my belief that with the entire cable coated with grease, the cable rides on a hydrodynamic wedge of lubricant all the time. Much like the way a main bearing in an engine works...the cable actually never touches the wall of the tubing under normal conditions..

The problem I see with these oil drip systems is, there can never be enough flow of oil to create this shear wedge... think about it, a main bearing in an engine is working under perfect conditions to live...
Polished journal, babbitt main bearing. oil being pumped in at 40 psi to create the hydrodynamic wedge, oil carrying off the heat.. all with several quarts of oil to be recirculated, filtered and reused.

Maybe if the cable had a large oil tank, oil pump, and recirculation system, I'd be impressed...
Otherwise I think the cable is merely surviving under poor application..

Having to cool a shaft log is merely treating a symptom, not curing the problem.

Just my .02..

I love my .45 boats,,good ol 3/16 flex running in a teflon liner,,glacier/lead teflon bearings,,smear of grease,,go all day

 

[Wasted wages]

I would argue that this was caused by an out of balance condition on the prop...and not lack of lube..

Reason I say that is there is no way it made that much heat and didn't discolor the aluminum strut tube or more of the shaft, or take out the strut tube completely..

Now, if the shaft was being flexed sideways back and forth by an out of balance condition,
much like you would bend a paperclip,,
THAT would concentrate a specific heat point that may have allowed that shaft to get hot enough and twist in that one spot.... he got real lucky that the prop still stayed attached...

 

[Hydro Junkie]

I would have to agree with WW on this one. It is a balance issue, but not the prop. The problem is the set screw that secures the drive dog to the shaft. It may seem like a non-issue but, with the set screw being that long, it unbalances the shaft. The excess set screw length weight caused the shaft to whip and, once started, the weight of the prop made things worse and very quickly.

 

[Wasted wages]

Good eye, I didn't notice that long set screw in the drive dog... I was thinking maybe the prop picked up some trash from the water...piece of poly rope, fishing line...
I've seen props vibrating and dancing all over the place on boats running on the stand, seen a few snap off too...

 

[Hydro Junkie]

I was initially thinking an unbalanced prop as well. Had an almost paragraph long post and then noticed the long set screw in this picture:


What I noticed is that the set screw is pointed toward the general direction of the bend in the shaft and, having used overlength set screws in the past myself and knowing how much damage that I had on my first two boats because of the unbalanced shafts.......

 

[Daniel's Racing]

I pulled it out. I took the pictures.

It merrily went dry. For certain. I was there. I saw it. Bone frigging dry and the ONLY reason it occurred.

Nothing out of balance caused this. Same driveline/prop on Pats boat for months maybe years.

You can see the melt/bend actually occurred up in the bushing with brass marking up the shaft on either side of the melted portion.

It 100% for sure was run bone dry and it got so hot it melted the shaft. That is all that was going on. Complete coincidence it went in direction of the setscrew I would say but who knows but for sure the melted and bent shaft was not caused by a out of balance condition. The entire driveline went bone dry because Pat skimped on the lube session that day.

The driveline was replaced and the boat ran another year with the same prop that had already been on the boat for probably a year. Pat was not a prop guy. He had pretty much one good prop for each boat.