Moparts

what causes a driveshaft to fall out?

Posted By: ashburnmike

what causes a driveshaft to fall out? - 10/28/09 11:50 PM

I took my dart for a test run with a new edelbrock carburator last Sunday...was running fine....then the driveshaft hit the pavement. It has less than 200 miles on the road.
what could cause this? Did I forget to do something? took me by surprise.
here is a pic of the ujoint.

Attached picture 5572827-universaljointtwosides.jpg
Posted By: Commando1

Re: what causes a driveshaft to fall out? - 10/29/09 12:02 AM

Need more details.
WAAAAaaaaaay more details.
You install a carb and the driveshaft falls out?
Posted By: viperakron

Re: what causes a driveshaft to fall out? - 10/29/09 12:08 AM

Where are the caps?
Posted By: dave571

Re: what causes a driveshaft to fall out? - 10/29/09 12:11 AM

Typically something breaks, to cause a shaft to come out.

BUT....
Something like what's in the pic, could be caused by forgetting to put the snap rings on the caps. Without a snap ring, the cap just flys outward under the straps.
Posted By: meepmeep70

Re: what causes a driveshaft to fall out? - 10/29/09 12:11 AM

broken bolts in rear?looks like that little vibration must have been missing bolts and clamp on one side,200 miles nothing?
Posted By: RapidRobert

Re: what causes a driveshaft to fall out? - 10/29/09 12:24 AM

Mike did a strap bolt come loose or a needle bearing get moved out of place around the perimeter if a cap was taken off & put back on. When R&R ing a ujoint both ears on that end of the shaft need to be whacked between the shaft & the half moon ujoint cap with a medium blow w a bfh to align the ears back after the ujoint caps are pressed in so. Test by moving the cross (rear)back & forth in it's plane & the front yoke (front) in both its planes & it should be free & no roughness/binding. How did our joint venture on the carb turn out?. Found out you cant send metering rods in the mail because their machines have a problem w metal even a minute amt in an envelope. We were lucky one rod showed up! they must have figured it wasn't a terrorist device & resealed the envelope & sent it on it's way.
Posted By: 440challenger

Re: what causes a driveshaft to fall out? - 10/29/09 01:18 AM

I think the circlips were not installed
Posted By: MoparforLife

Re: what causes a driveshaft to fall out? - 10/29/09 01:29 AM

I agree that the circlips were not installed to keep the cross/caps centered in the yokes and also so thatthe rotation cannot push them out. Also is it an apticla illusion or does the left side cross look to have been real warm. (Hot)
Posted By: ashburnmike

Re: what causes a driveshaft to fall out? - 10/29/09 02:06 AM

Quote:

Where are the caps?




when I rolled to a stop on the side of the road this was all that was on the u joint. I took the DS out tonight and took the picture of it.
Posted By: ashburnmike

Re: what causes a driveshaft to fall out? - 10/29/09 02:12 AM

Quote:

Typically something breaks, to cause a shaft to come out.

BUT....
Something like what's in the pic, could be caused by forgetting to put the snap rings on the caps. Without a snap ring, the cap just flys outward under the straps.




I had the u joint pressed in the shaft by a local shop so a)I don't know if any snap rings were there at all to begin with and b) I didn't look for any as I didn't know there ws supposed to be any there in the first place and c) I just put it up on the yoke and torqued the two straps up. uh oh
Posted By: ashburnmike

Re: what causes a driveshaft to fall out? - 10/29/09 02:14 AM

Quote:

broken bolts in rear?looks like that little vibration must have been missing bolts and clamp on one side,200 miles nothing?




the two straps and the bolts that held the ujoint to the rear are both in place and tight.
Posted By: 1_WILD_RT

Re: what causes a driveshaft to fall out? - 10/29/09 02:18 AM

Quote:

Quote:

broken bolts in rear?looks like that little vibration must have been missing bolts and clamp on one side,200 miles nothing?




the two straps and the bolts that held the ujoint to the rear are both in place and tight.




Well then consider the missing clips confirmed... Learning curve just got an extra bend..
Posted By: ashburnmike

Re: what causes a driveshaft to fall out? - 10/29/09 02:26 AM

Quote:

Mike did a strap bolt come loose or a needle bearing get moved out of place around the perimeter if a cap was taken off & put back on. When R&R ing a ujoint both ears on that end of the shaft need to be whacked between the shaft & the half moon ujoint cap with a medium blow w a bfh to align the ears back after the ujoint caps are pressed in so. Test by moving the cross (rear)back & forth in it's plane & the front yoke (front) in both its planes & it should be free & no roughness/binding. How did our joint venture on the carb turn out?. Found out you cant send metering rods in the mail because their machines have a problem w metal even a minute amt in an envelope. We were lucky one rod showed up! they must have figured it wasn't a terrorist device & resealed the envelope & sent it on it's way.




haha, remember Robert, we think terrorist attack all the time here in the Washington DC area...lately it's been from Congress and the White House on we, the American taxpayers.
I gave up on the AVS and borrowed a Edelbrock performer 600cfm from someone locally. Thats was I was testing when this occured.
Posted By: ashburnmike

Re: what causes a driveshaft to fall out? - 10/29/09 02:39 AM

Quote:

I think the circlips were not installed




I just googled circlip to find out what they are.
I DID NOT put any circlips or snap rings on when I put the drive shaft on the yoke.
I just put the straps over the u joint and tightened them down.
Thank you gents for the education and that "learning curve just got another bend" comment is great.
keeps me from being in this situation

Attached picture 5573310-Ontherollbackonwaxpool.jpg
Posted By: RapidRobert

Re: what causes a driveshaft to fall out? - 10/29/09 02:50 AM

The ujoint box contains the new loose clips whether you buy it at a parts store or it is delivered to their shop. The shop should have pushed the clips onto the caps when they did the R&R. & if not they should have gave them to you when you picked up the shaft but there is no reason that they wouldn't have taken a few seconds to push them on the caps to finish the job before the shaft goes out the door to the customer.
Posted By: Reggie

Re: what causes a driveshaft to fall out? - 10/29/09 03:43 AM

Closely inspect that driveshaft if you plan on reusing it. Even a small ding can cause a vibration. Been there.
Posted By: RapidRobert

Re: what causes a driveshaft to fall out? - 10/29/09 04:05 AM

Quote:

I gave up on the AVS


Mike does that mean you took my portfolio down from your garage wall?
Posted By: phantomx

Re: what causes a driveshaft to fall out? - 10/29/09 04:38 AM

I kicked a driveshaft out of my 67 Barracuda once. I had just swapped the 3rd member and used a new set of u-joint straps. Turned out they were for the larger joint. They bolted on fine, but they did not stretch down over the caps, they fit flush without bolts. I didn't notice and used them. I took off down the road and up around 70mph my driver door started to vibrate. I thought to myself, "that's odd, never done that before", just then KABAAAMMM...thumpeta..thumpetaaaa. That sucked. Had the driveshaft repaired,installed with new correct straps, hammered the floor back down (big dent on rear seat footwell tunnel)and hit the road. After that it had a tiny vibe in the upper MPHs. A couple of months later I found out what the vibe was. I pulled off the freeway on a lonely offramp heading for my friends house and while gently pulling away from the stop sign, click, tink tink tink.. Looked under the car and there is the driveshaft on the ground with the yoke and half of the pinion still attached I'm glad that didn't happen moments before as I was playing with a Camaro at 100+mph. Appearently the original driveshaft pop-out episode caused a fracture in the pinion and it finally gave way. I am 100% certain on what straps I use on u-joints now. That learning curve nearly had a u-turn in it.
Travis..
Posted By: MoparforLife

Re: what causes a driveshaft to fall out? - 10/29/09 10:33 AM

By the way look at the other 2 cups that ate pressed into the drive shaft yoke. There should be cir clips on them also. They will be in a groove in the cup just to the inside of the driveshaft flange.
Posted By: ashburnmike

Re: what causes a driveshaft to fall out? - 10/29/09 12:02 PM

Quote:

Quote:

I gave up on the AVS


Mike does that mean you took my portfolio down from your garage wall?




no sir ! those custom covers you made have a permanent spot on my garage wall.
Posted By: BigBlockMopar

Re: what causes a driveshaft to fall out? - 10/29/09 12:03 PM

I can confirm that U-joints without circlips can also fail at 110mph.
That was my learning curve many years ago.
Posted By: ashburnmike

Re: what causes a driveshaft to fall out? - 10/29/09 12:05 PM

Quote:

The ujoint box contains the new loose clips whether you buy it at a parts store or it is delivered to their shop. The shop should have pushed the clips onto the caps when they did the R&R. & if not they should have gave them to you when you picked up the shaft but there is no reason that they wouldn't have taken a few seconds to push them on the caps to finish the job before the shaft goes out the door to the customer.




Robert, I didn't notice the weren't there but I also didn't know enough to look to see if they were there. I'll certainly look alot closer this time.
Posted By: ashburnmike

Re: what causes a driveshaft to fall out? - 10/29/09 12:09 PM

Quote:

Closely inspect that driveshaft if you plan on reusing it. Even a small ding can cause a vibration. Been there.




the shaft end is a little scraped up where it hit the pavement. I'm going to try and reuse it as my budget is a little tight these days. But if I sense any vibration during the test run...I'll replace it.I can imagine the vibration could turn into more serious problems.
Posted By: ashburnmike

Re: what causes a driveshaft to fall out? - 10/29/09 12:10 PM

Quote:

By the way look at the other 2 cups that ate pressed into the drive shaft yoke. There should be cir clips on them also. They will be in a groove in the cup just to the inside of the driveshaft flange.




will do, thanks
Posted By: ashburnmike

Re: what causes a driveshaft to fall out? - 10/29/09 12:12 PM

Quote:

I can confirm that U-joints without circlips can also fail at 110mph.
That was my learning curve many years ago.




110mph? holy mackeral!
Posted By: JohnRR

Re: what causes a driveshaft to fall out? - 10/29/09 12:16 PM

Quote:

Quote:

Closely inspect that driveshaft if you plan on reusing it. Even a small ding can cause a vibration. Been there.




the shaft end is a little scraped up where it hit the pavement. I'm going to try and reuse it as my budget is a little tight these days. But if I sense any vibration during the test run...I'll replace it.I can imagine the vibration could turn into more serious problems.




I would take it back to the shop that put in the last joint , ask if he gave you the other clips or put then on the caps , and make sure you get them THIS TIME , and have them spin the shaft , makes no sense to the job twice ...
Posted By: ashburnmike

Re: what causes a driveshaft to fall out? - 10/29/09 12:19 PM

Quote:

I kicked a driveshaft out of my 67 Barracuda once. I had just swapped the 3rd member and used a new set of u-joint straps. Turned out they were for the larger joint. They bolted on fine, but they did not stretch down over the caps, they fit flush without bolts. I didn't notice and used them. I took off down the road and up around 70mph my driver door started to vibrate. I thought to myself, "that's odd, never done that before", just then KABAAAMMM...thumpeta..thumpetaaaa. That sucked. Had the driveshaft repaired,installed with new correct straps, hammered the floor back down (big dent on rear seat footwell tunnel)and hit the road. After that it had a tiny vibe in the upper MPHs. A couple of months later I found out what the vibe was. I pulled off the freeway on a lonely offramp heading for my friends house and while gently pulling away from the stop sign, click, tink tink tink.. Looked under the car and there is the driveshaft on the ground with the yoke and half of the pinion still attached I'm glad that didn't happen moments before as I was playing with a Camaro at 100+mph. Appearently the original driveshaft pop-out episode caused a fracture in the pinion and it finally gave way. I am 100% certain on what straps I use on u-joints now. That learning curve nearly had a u-turn in it.
Travis..




the comforting part of this whole event from all the help and suggestions you guys made is...apparently I'm not the first...and certainly won't be the last...to be on the side of the road, laying under the car thinking..."what did I do wrong to cause this?"
Posted By: therocks

Re: what causes a driveshaft to fall out? - 10/29/09 12:45 PM

That rear dose have the large yoke does it?Over the years lots of things get changed.Like said look at the joint in the shaft.You should see 2 clips on the inside part.Two also go on the 2 ends at the rear and also like said check that the straps are for the small joint.I think somethin should at least be bent even if the caps flew off.Double check everything.Was the rear and straps in the car before and was anything changed other than the joint?Rocky
Posted By: ashburnmike

Re: what causes a driveshaft to fall out? - 10/30/09 03:52 PM

Quote:

That rear dose have the large yoke does it?Over the years lots of things get changed.Like said look at the joint in the shaft.You should see 2 clips on the inside part.Two also go on the 2 ends at the rear and also like said check that the straps are for the small joint.I think somethin should at least be bent even if the caps flew off.Double check everything.Was the rear and straps in the car before and was anything changed other than the joint?Rocky [/quote

it's an 8 3/4" rear. I bought the 3.91 assembly from Randy's ring and pinion. I had a shop install it because I didn't know how to do that kind of work. I had the same guys install the new u joint on the driveshaft at the same time. I was told that it needed to be pressed in place and not just hammered in on the driveshaft. I put the driveshaft in the trans and hooked it up (incorrectly, I know now) to the rear. I don't remember ever putting any snap rings in place when I put it in.
I'll take a super close look at it this time...and will take pictures and send them out to the board members to make sure I don't install it wrong again.
thanks Rocky
Mike
Posted By: 68KillerBee

Re: what causes a driveshaft to fall out? - 10/31/09 04:11 AM

First drive with my car... No windows (check), 50 degree weather (check), toolbox for me to sit on and bucket for mom (check), circlips missing (check). haha. made it around the subdivision then heard ping ping ping ping. dad realized instantly what he did haha. tow strap up the drive from the bottom of the hill. no wonder my mom doesn't like riding in it haha
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