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RayH

3416H driveshaft Length?

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RayH
While tearing down my 3416H to repaint, I noticed the drive shaft flange was on the BGB drive shaft by no more than 1/2 inch. In fact. the drive shaft key was rotating and tearing the metal on the BGB drive shaft. I dressed the shaft up to get the flange back on without having to beat the living H _ LL out of it. I am now wondering if some previous owner has replaced the drive shaft with a shorter drive shaft and this would be the reason for the flange being so far forward on the BGB drive shaft. There is no reference that I can find in the Manuals that give the length of the drive shaft. What is the correct drive shaft length for a 3416H tractor? Ray

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thedaddycat
I don't know the length of the drive shaft, but I can tell you how I adjusted mine after I put in the cross plates of my support plate project. Since the rear cross plate located the BGB 3/16" farther back I was getting less yoke engagement than I was comfortable with. I used 1/2" spacers between the rear flex-disc and the yoke, moving the yoke back onto the BGB input shaft. The front end also has spacers/washers and one set of bolts through the flex-disc has short stiff springs under the bolts. I can take pics and post them tonight after I get home if you'd like to see how I did it.

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Al
Hi, I would sooner think they don't have all the hardware in the system. Note that the special washers that face the flex plates have a rounded and a flat side. It is imperitive that the rounded side be against the plate on both sides of the flex plate. If they are put on backwards they can cause a round chunk the size of the washer to break out and the driveshaft will fly and all hell breaks loose. These driveshafts usually come out bent in a v or u.about 45 degrees. Regardind the springs, I personally would not be comfortable with them. The washers need to be tight and "crush" against the disk to transmit the torque. If they get the least bit loose, it doesn't take 5 minutes for the holes in the disk to egg out and in a few minutes the driveshaft flies as above. The disks have no lasting resistance to vibration and pressure edgewise they wear very fast. Have no idea what the springs are like, but personally I would be afraid of them. DO NOT INTERPET THIS TO MEAN I SAY YOU ARE WRONG. I am respectfully just stating my thoughts, they are free so value accordingly. Good luck, Al Eden

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HubbardRA
I have swapped several engines, and I adjust the fit on the bevel gear shaft by adding the spacers at the engine. This way all of the flex joints remain configured like they were from the factory. In fact, I never tighten the set screw on the BGB yoke until all other bolts of the driveshaft are torqued. This way there is no tension or preload on the couplings that could cause premature failure from fatigue. Rod H.

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thedaddycat
Though I would like to take credit for the spring idea it isn't mine. The tractor came that way and my friend who owned it before me said it was that way when he got it too. It has held up since at least the early 80's so I have no worries about it lasting. I tried to post pics last night but couldn't get on the site. It kept coming up as not configured at that address or some such thing. I just tried again and it keeps coming up as "Save Failed"

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Kent
Kirk, Try uploading your picture now. The site was moved to a different server yesterday, and I failed to get the file permissions set on the directory where those pics get stored. It should work now... Kent The foot-draggin' Clubhouse Custodian...

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MikeES
Check your engine mount location. The way I install a drive shaft; is to install it on the BGB end and then connect the engine end WITH THE ENGINE MOUNTS LOOSE. Silde the engine back to mate up to the coupling disk. This way the disk couplings are flat and not being pulled or pushed. Good Luck! Mike S.

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Al
Hi, I tend to lean with Rod, In our repower kits, we stress getting the BGB shaft clean and leave the set screw loose until there is no push or pull on the flex plates. Last thing tighten the screw. My 2 cents worth, its free value accordingly. Al Eden

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RayH
Thanks for the responses on this Gents ! The drive shaft is 18 inches exactly. When I bought this tractor the engine was in pieces sitting in a cardboard box, along with a heaping handfull of hardware. The spacers were still sitting on the attaching bolts...so I tend to believe they were being used when the previous owner removed the engine. The length of the slots in the tractor frame looks to be about 1 inch, so that should give some fore/aft adjusment to mate the driveshaft without "flexing" the drive disks. Thanks Ray

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thedaddycat
OK then, we're back in business.... Kent the Magician has made the uploading work once again, Thanks Kent! The first pic shows how the drive shaft is attached to the engine. The springs are compressed by the bolts holding the drive shaft to the flex disc. There are spacers between the flex disc and both the drive shaft and the engine. The camera wouldn't fit up past the electric lift too well so the pic is not that great. I should have rotated tha drive shaft for a better look at it. You can see the spacer I added to the left of the end of the bolt threads(it's one of the bolts holding the support plates to the frame), between the BGB input shaft yoke and the flex disc.

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