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I had a scraping noise on my '84 Venture earlier this sping. It was suggested that I clean and grease the driveshaft. Did that and it was needed. I thought maybe the noise seemed to go away but now its back. I can feel a scrape (in the floorboards) when I am crawling forward in first gear. Does my driveshaft need to be done again ? What about the U-joint ? Has anyone had this problem and traced it to a bad U-joint ? Any other ideas ?

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Thanks Dan.

 

I'm embarrassed to say I had not thought of running it in first gear on the center stand. I did however try rotating the back wheel and I that's why I don't think its a dragging brake. I've read the threads that suggest that U-joints rarely go so I don't want to dismantle everything that needs to come apart just to check it unless I am reasonably sure that is the issue.

 

I was hoping someone had similar issues but it would appear otherwise. I'll try running the bike on the stand but I have a sneaking suspicion that I would hear the scraping. Although the back wheel does not spin as freely as the front, I don't hear a scrape when I spin it so that's why I think it ain't a brake issue. The U-joint must also be spinning when the bike is on its stand and I am manually spinning the back wheel but I still don't get the scraping noise. I am thinking U-Joint because my weight on the bike probably changes the angle on the knuckle.

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Thanks Dan.

 

I'm embarrassed to say I had not thought of running it in first gear on the center stand. I did however try rotating the back wheel and I that's why I don't think its a dragging brake. I've read the threads that suggest that U-joints rarely go so I don't want to dismantle everything that needs to come apart just to check it unless I am reasonably sure that is the issue.

 

I was hoping someone had similar issues but it would appear otherwise. I'll try running the bike on the stand but I have a sneaking suspicion that I would hear the scraping. Although the back wheel does not spin as freely as the front, I don't hear a scrape when I spin it so that's why I think it ain't a brake issue. The U-joint must also be spinning when the bike is on its stand and I am manually spinning the back wheel but I still don't get the scraping noise. I am thinking U-Joint because my weight on the bike probably changes the angle on the knuckle.

 

Check with Friesman on this one. After VWIV his lower engine is a basket case. He can fill you in on the details of what caused it...

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I had a scraping noise on my '84 Venture earlier this sping. It was suggested that I clean and grease the driveshaft. Did that and it was needed. I thought maybe the noise seemed to go away but now its back. I can feel a scrape (in the floorboards) when I am crawling forward in first gear. Does my driveshaft need to be done again ? What about the U-joint ? Has anyone had this problem and traced it to a bad U-joint ? Any other ideas ?

 

I thought mine was a lightly dragging brake from time to time i would hear it. And occasionally when i would go over a bump it would change the angle somehow and i would feel something rubbing down low on the pegs, but couldnt track it down as the ujoint looked ok. I started leaking oil about a month ago from the left lower side and asked 3 different techs to try and find the leak but no success, but i got almost all the gaskets changed in the process. Finally at VWIV it started flinging lots of oil out the back and the trans started to whine even louder until i got a loud bang at low speed and lost all forward motion. I am not a mechanic so it was described to me as the seal around the trans output shaft was worn and leaking causing the output shaft to be slightly out of align wearing the gears on the final driveshaft finally breaking them causing the gears to lockup snapping the shaft in front of the ujoint.

 

So in short check your output shaft seal and bushing.

 

Brian

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look where your driveshaft ujoint goes into the transmission housing on the left side and check for leaks and side to side play.

To make you feel better the mechanic that looked at mine in SLO had never seen it happen before and neither had the guys at a local salvage shop around town here but it is worth having a look.

I am not sure whether a bushing could allow enough play for that to happen, and Ive talked to a couple of other mechanics since I was at VWIV and their opinion is that there was likely a flaw in the gear first, setting up a vibration that took out the oil seal. to me it seems a bit more likely to have happened this way but I am a computer geek not a mechanic so who really knows what caused all the carnage!!!:confused24::confused24:

 

All i know is if you get an oil leak, and you hear scraping, check your output shaft bushings....

 

Brian

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I thought mine was a lightly dragging brake from time to time i would hear it. And occasionally when i would go over a bump it would change the angle somehow and i would feel something rubbing down low on the pegs, but couldnt track it down as the ujoint looked ok. I started leaking oil about a month ago from the left lower side and asked 3 different techs to try and find the leak but no success, but i got almost all the gaskets changed in the process. Finally at VWIV it started flinging lots of oil out the back and the trans started to whine even louder until i got a loud bang at low speed and lost all forward motion. I am not a mechanic so it was described to me as the seal around the trans output shaft was worn and leaking causing the output shaft to be slightly out of align wearing the gears on the final driveshaft finally breaking them causing the gears to lockup snapping the shaft in front of the ujoint.

 

So in short check your output shaft seal and bushing.

 

Brian

Something is probably worn, allowing the shaft to move and damage the lip of the seal. Seals don't support shafts, they seal against the shaft to prevent oil from leaking and prevent dirt and moisture from getting in. Ronnie

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Something is probably worn, allowing the shaft to move and damage the lip of the seal. Seals don't support shafts, they seal against the shaft to prevent oil from leaking and prevent dirt and moisture from getting in. Ronnie

 

Yep I would say the final drive gear out my trans is worn a bit alright and it broke off the shaft just in front of ujoint as well.

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I am not a mechanic so it was described to me as the seal around the trans output shaft was worn and leaking causing the output shaft to be slightly out of align wearing the gears on the final driveshaft finally breaking them causing the gears to lockup snapping the shaft in front of the ujoint.

 

.

 

Brian

 

This may be a chicken or egg thing. I suspect the shaft broke first at the u-joint causing the rest of the damage. This happened to several members a while back.

RandyA

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This may be a chicken or egg thing. I suspect the shaft broke first at the u-joint causing the rest of the damage. This happened to several members a while back.

RandyA

 

IT started making grinding noises but I was still able to move forward slowly and was trying to get the bike to a shop when the shaft broke and stopped all forward movement with a bang, So i think the gears were the issue first.

 

Brian

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Wonder if it started with the crush sleeve at the u-joint mount being loose and not retightened? That would allow play in the middle pinion gear setup, poosibly allowing the damage to the pinion. Looks like the pinion gear was eating into the driven axle pinion, be interesting to see what that looks like. Should be able to view it thru the case opening where you took this shaft out of. If it's bad too, you'll have to break open the case to replace the gear.

Dang, THAT HURTS!!!!!!!!

 

Dan

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IT started making grinding noises but I was still able to move forward slowly and was trying to get the bike to a shop when the shaft broke and stopped all forward movement with a bang, So i think the gears were the issue first.

 

Brian

 

The reason I suspected the shaft breaking at the nut first was if this happens, the output shaft is still contained and the u-joint coupling splines will contain the driveshaft/u-joint coupler, but what you end up getting is a lot of meshing on the two 90 degree gears. After a while it will get so bad that it tears up the teeth like yours did. Remember, what keeps the gear mesh in the correct range is the nut on the u-joint coupler. If the nut breaks, you can still ride the bike for awhile, it will just get more and more noisy until the gears or bearing fails. It appears you rode it for a while with severe gear mesh problems, with the nut broke off.

Again, the nut breaking on the output shaft is not a real uncommon problem. It is just most will hear the increased noise and investigate it before more severe damage is done..

RandyA

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The reason I suspected the shaft breaking at the nut first was if this happens, the output shaft is still contained and the u-joint coupling splines will contain the driveshaft/u-joint coupler, but what you end up getting is a lot of meshing on the two 90 degree gears. After a while it will get so bad that it tears up the teeth like yours did. Remember, what keeps the gear mesh in the correct range is the nut on the u-joint coupler. If the nut breaks, you can still ride the bike for awhile, it will just get more and more noisy until the gears or bearing fails. It appears you rode it for a while with severe gear mesh problems, with the nut broke off.

Again, the nut breaking on the output shaft is not a real uncommon problem. It is just most will hear the increased noise and investigate it before more severe damage is done..

RandyA

 

Now that you describe it that way, its possible that is what has happened, as I was 1800 miles from home and trying to get it to a shop to have a look when it totally quit after making grinding noises. I knew i was doing damage but I wanted to get ol' brownie looked after... but I only made it 3 or 4 miles , if that.

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