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-   -   Dropped a straw in my gearbox!!!! (https://www.cruisersforum.com/forums/f54/dropped-a-straw-in-my-gearbox-233960.html)

Swift Drift 08-05-2020 16:10

Re: Dropped a straw in my gearbox!!!!
 
1 Attachment(s)
Quote:

Originally Posted by a64pilot (Post 3135256)
Clutches should be in packs, like a motorcycle clutch if you have ever had one of them apart, I donít see how they could be hurt, but I can see how a tube may jam gears, it may eat it too, but it may bust something too as that ďstrawĒ is pretty tough.
Iíd want it out. Me, if I couldnít get it out with a scope and mechanical fingers, would remove the tranny, turn it upside down and shake it, it might work, and if not take it to a shop and have them disassemble and inspect everything and replace any worn parts, may as well start with a known good tranny if you have to pay to have it taken apart.

I think you will see it with a camera myself, itís stiff so it didnít go far. Get some mechanical fingers though so you can get it when you see it.
https://www.amazon.com/s?k=Mechanica...f=nb_sb_noss_2

I have a KBW-20 also and so Iím a little familiar.



Thanks for chiming in. Iíve followed much of your activity on this forum as you and I have the same drivetrain and I respect your mechanical prowess.
I think your assessment is right. I now have the side plate off and will try to source mechanical fingers and a endoscope locally if I can. If not, sounds like Iím pulling the unit. This would be stressful under normal circumstances but there is another layer now as I could get a green light to enter Grenada at any moment but may miss my window with this situation.

Attachment 214648

Orion Jim 08-05-2020 16:26

Re: Dropped a straw in my gearbox!!!!
 
Quote:

Originally Posted by Swift Drift (Post 3135290)
Thanks for chiming in. Iíve followed much of your activity on this forum as you and I have the same drivetrain and I respect your mechanical prowess.
I think your assessment is right. I now have the side plate off and will try to source mechanical fingers and a endoscope locally if I can. If not, sounds like Iím pulling the unit. This would be stressful under normal circumstances but there is another layer now as I could get a green light to enter Grenada at any moment but may miss my window with this situation.

Attachment 214648

A fair number of cruisers carry the cheap endoscopes (they are currently available on Amazon and eBay for as little as 7 bucks and decent units go for 35 bucks) which pair with apps on your cellphone. You may just find someone anchored nearby willing to lend you theirs.

Swift Drift 08-05-2020 17:47

Re: Dropped a straw in my gearbox!!!!
 
Quote:

Originally Posted by Orion Jim (Post 3135301)
A fair number of cruisers carry the cheap endoscopes (they are currently available on Amazon and eBay for as little as 7 bucks and decent units go for 35 bucks) which pair with apps on your cellphone. You may just find someone anchored nearby willing to lend you theirs.



Good thought. Iím going to try and source an endoscope and ďmechanical fingersĒ tomorrow. Even if I can get my hands on them Iím not holding my breath that Iíll be enable to extract the tube.

maine50 08-05-2020 18:04

Re: Dropped a straw in my gearbox!!!!
 
It might make sense to try one of the many diesel shops in Antigua. Power Systems is one,(Falmouth harbor) not far from Catamaram Marina and there's another one in Jolly Harbor. They might have the tools and knowledge.

a64pilot 08-05-2020 18:05

Re: Dropped a straw in my gearbox!!!!
 
Gears are set up with “lash” that means a little clearance between them, looseness if you will, but it’s not much at all, toss something in between them and that forces the gears apart and could worst case bust something.
Add to that that the gears in the KBW-20 are helical cut gears, that means the teeth are at an angle, that makes the gears run quieter but isn’t quite as strong as straight cut gears.
Helical cut gears when under a load get forced sideways, in this instance that lateral force is used to force the clutches tighter, pretty brilliant design in my opinion as it means the clutches have weak springs so that the shift lever is easy to move, however the more force applied to the gears the tighter the clutch plates are pressed together and that keeps them from slipping, so you get both a strong clutch, and an easy to shift transmission that the more torque fed through it, the tighter the clutches get to pass that torque along without slipping.
However put something in between the gears and that force could go through the roof and that could bust something, a gear or maybe a clutch pack, or maybe nothing, but I wouldn’t want to chance it far from home.

Sailmonkey 08-05-2020 19:02

Re: Dropped a straw in my gearbox!!!!
 
Quote:

Originally Posted by a64pilot (Post 3135377)
Gears are set up with ďlashĒ that means a little clearance between them, looseness if you will, but itís not much at all, toss something in between them and that forces the gears apart and could worst case bust something.
Add to that that the gears in the KBW-20 are helical cut gears, that means the teeth are at an angle, that makes the gears run quieter but isnít quite as strong as straight cut gears.
Helical cut gears when under a load get forced sideways, in this instance that lateral force is used to force the clutches tighter, pretty brilliant design in my opinion as it means the clutches have weak springs so that the shift lever is easy to move, however the more force applied to the gears the tighter the clutch plates are pressed together and that keeps them from slipping, so you get both a strong clutch, and an easy to shift transmission that the more torque fed through it, the tighter the clutches get to pass that torque along without slipping.
However put something in between the gears and that force could go through the roof and that could bust something, a gear or maybe a clutch pack, or maybe nothing, but I wouldnít want to chance it far from home.



Iíd worry about cracking the gear case more than damaging the actual gears or clutches.

paralog 08-05-2020 19:06

Re: Dropped a straw in my gearbox!!!!
 
refill the gearbox to see it you can get it to float to the top.

mlydon 08-05-2020 19:17

Re: Dropped a straw in my gearbox!!!!
 
Ha - I was going to suggest floating it, but paralog beat me to it. Before trying though, see if the tubing floats in oil at all - do you have another piece you can test with?

Matt

Swift Drift 08-05-2020 20:19

Re: Dropped a straw in my gearbox!!!!
 
2 Attachment(s)
Good thoughts on floating. Iím going to do my best to extract without pulling the gearbox. If I need to pull and disassemble the gearbox, it appears fairly straightforward: I coupe and slide back shaft, unbolt housing from back of engine so I can access internal bolt heads holding gearbox to housing, then wrestle it out. Once out if I need to dig deeper yet, remove forward of box via bolts circled in picture below.

Am I missing something?
Attachment 214657
Attachment 214658

kmacdonald 08-05-2020 20:21

Re: Dropped a straw in my gearbox!!!!
 
I wouldn't run it with the straw in there. Take the gear off, pour the oil out and turn it upside down, shake it, etc, and figure out a way to get it out of the hole. If you're lucky you wont have to disassemble the gear. When you see the straw you could push a slightly tapered cone in the straw end until the cone bottoms out in the straw. Then pull it out. I don't know if that will work but you could try. Removing the gear is not a big deal at all. Half hour max.

You might even be able to get it without removing the gear.

mlydon 08-05-2020 20:39

Re: Dropped a straw in my gearbox!!!!
 
If you can pull a tranny in half an hour, you’re my new hero for life.

Matt

kmacdonald 08-05-2020 21:01

Re: Dropped a straw in my gearbox!!!!
 
Well, maybe 35 minutes.

jimbunyard 08-05-2020 22:27

Re: Dropped a straw in my gearbox!!!!
 
3 Attachment(s)
Quote:

Originally Posted by Swift Drift (Post 3135228)
I really want to believe this.... what about my clutches? Could they get messed up and not make proper contact, etc?

As previously noted, I don't expect you (nor anyone else who has little-to-no experience with these things) to 'believe' this advice.

10w40 motor oil has a specific gravity of about .857 g/cm3, polyethylene is .957, so it's not likely that it will float, unless you fill the box with something other than the recommended lube, which will almost certainly do more harm than the straw itself.

The 'meshing gears' in this transmission are located high in the housing, the straw will be located under the clutch pack, which cannot be affected by the straw.

Should the spinning oil cause the straw to be pushed up into the top of the transmission where it could conceivably (though it is very very unlikely) contact the gears that mesh with each other, the typical reaction is to push the alien object away, not draw it in.

In this case even if they somehow sucked it in, the gears wouldn't even notice it, the difference in hardnesses of the two materials is just too great.

The only real (however remote) problem would be that the straw somehow got into the shifting mechanism, and caused problems there, but again, steel and brass/bronze are so much stronger than the plastic of the straw that any problem would likely be short-lived .

Again, I don't think any of this this will assuage your concern, so if you take the shift cover off you'll probably be able to drag the offending item out from that side by using a thin hooked wire bent to thread under the clutch pack. If you're near a tig welder, a piece of 1/16" tig wire works really well for things like this...

Jim Cate 08-05-2020 23:28

Re: Dropped a straw in my gearbox!!!!
 
^^^^^

Sounds like good advice to me. More likely to do harm mucking about than leaving it be.

But I too understand the reluctance to do this!

Good luck... may the force show you the way!

Jim

GoneDiving 09-05-2020 02:17

Re: Dropped a straw in my gearbox!!!!
 
A totally unqualified suggestion:

Drain the oil out the bottom then use this port to blow the tube out the top with a blast of compressed air?

Of course residual oil is also going to be blown out and go everywhere. 😁

I have no idea if/what seals could be damaged by 100psi of internal pressure.


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