The trans in my bus was recently rebuilt but has started to get stuck in 3rd gear. It shifts fine, but once you put it in 3rd, it wont come out and you need to pull over and shut down. When the motor is off, it comes out of 3rd just fine.
Any ideas as to why this happens?
Kurt
trans gets stuck in 3rd
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germansupplyscott
- Posts: 887
- Joined: Fri Jul 20, 2001 12:01 am
trans gets stuck in 3rd
vwkurt,
since no-one else had tried this one, i will, but i am not the best one for trans issues, just not enough experience there. that said, there are a few questions:
this rebuilt trans, who rebuilt it, and who installed it? is the trans the original from the van, or a different unit? is the trans rebuilt or "reconditioned"? is the clutch new as well? clutch cable new?
also, once in third and running, can you ever shift into fourth? and also you said "started" to do this - how did it start, like the day after you had the repairs completed or something?
i would look at the clutch cable first. think of it - if your trans is fine, but you clutch cable breaks or it too loose, you cannot shift gears. why this would occur in third only from a cable problem, i don't know, but it is the simplest thing to check, that the cable is tight enough and correctly installed.
next, look at the shift rod. since the trans has been out of the van, this has all been apart, and perhaps there is a linkage alignment problem that can be fixed by adjusting the position of the trans. the linkage itself is not adjustable, but the location of the trans is, and sometimes shifting problems occur due to misalignment of the trans - the trans has a "U" shaped rubber and steel mount that is held onto the nosecone by a heavy bracket, held by two nuts. this bracket is an adjustment point - it has slotted holes. if you loosen these two nuts, as well as the four on the rear engine bearer (moustache bar) you can adjust the attitude of the motor/trans and that might fix your problem.
failing that, the symptoms point to a synchromesh problem with third gear. the synchro rings allow the gears to mesh while the engine is turning, they act as a kind of clutch inside the gearbox. if the third gear synchro is bad, it might cause the symptom you are having. this points to a bad rebuild, unfortunately, so let's hope that the cable is at fault. the VW transaxle is not an everyman rebuilable item. i have rebuilt other gearboxes, and i would not attempt to do a bus transaxle. i wouldn't even take one to most transmission shops for repair, so when you say you have a rebuilt trans, the little red lights go on...
the only way to establish that the problem is internal in the trans is to eliminate all clutch and linkage issues as potential first. internal trans problems are another story.
scott lyons
[This message has been edited by punkinfair (edited 01-17-2002).]
since no-one else had tried this one, i will, but i am not the best one for trans issues, just not enough experience there. that said, there are a few questions:
this rebuilt trans, who rebuilt it, and who installed it? is the trans the original from the van, or a different unit? is the trans rebuilt or "reconditioned"? is the clutch new as well? clutch cable new?
also, once in third and running, can you ever shift into fourth? and also you said "started" to do this - how did it start, like the day after you had the repairs completed or something?
i would look at the clutch cable first. think of it - if your trans is fine, but you clutch cable breaks or it too loose, you cannot shift gears. why this would occur in third only from a cable problem, i don't know, but it is the simplest thing to check, that the cable is tight enough and correctly installed.
next, look at the shift rod. since the trans has been out of the van, this has all been apart, and perhaps there is a linkage alignment problem that can be fixed by adjusting the position of the trans. the linkage itself is not adjustable, but the location of the trans is, and sometimes shifting problems occur due to misalignment of the trans - the trans has a "U" shaped rubber and steel mount that is held onto the nosecone by a heavy bracket, held by two nuts. this bracket is an adjustment point - it has slotted holes. if you loosen these two nuts, as well as the four on the rear engine bearer (moustache bar) you can adjust the attitude of the motor/trans and that might fix your problem.
failing that, the symptoms point to a synchromesh problem with third gear. the synchro rings allow the gears to mesh while the engine is turning, they act as a kind of clutch inside the gearbox. if the third gear synchro is bad, it might cause the symptom you are having. this points to a bad rebuild, unfortunately, so let's hope that the cable is at fault. the VW transaxle is not an everyman rebuilable item. i have rebuilt other gearboxes, and i would not attempt to do a bus transaxle. i wouldn't even take one to most transmission shops for repair, so when you say you have a rebuilt trans, the little red lights go on...
the only way to establish that the problem is internal in the trans is to eliminate all clutch and linkage issues as potential first. internal trans problems are another story.
scott lyons
[This message has been edited by punkinfair (edited 01-17-2002).]
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vwkurt
- Posts: 52
- Joined: Wed May 02, 2001 1:01 am
trans gets stuck in 3rd
Scott,
Thanks for the reply. The trans was rebuilt by a reputable VW only shop and was working fine. One day it was difficult to pull it out of third, but it came out. The next day it just got stuck and has ever since. I would point fingers at the rebuild if it happened from the beginning, but only started happening after a few weeks of driving daily. You do bring up a good point about the alignment and I was totally unaware of this. It does have a SCAT shifter as well which I wil replace with a stock one to eliminate that possibility.
Is there anywhere I can find the specifications for adjusting the trans?
Kurt
Thanks for the reply. The trans was rebuilt by a reputable VW only shop and was working fine. One day it was difficult to pull it out of third, but it came out. The next day it just got stuck and has ever since. I would point fingers at the rebuild if it happened from the beginning, but only started happening after a few weeks of driving daily. You do bring up a good point about the alignment and I was totally unaware of this. It does have a SCAT shifter as well which I wil replace with a stock one to eliminate that possibility.
Is there anywhere I can find the specifications for adjusting the trans?
Kurt
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rich2481
- Posts: 1539
- Joined: Tue Dec 18, 2001 12:01 am
trans gets stuck in 3rd
you say it can be taken out of third if you pull over and shut down, did you bleed your clutch out very well after you reinstalled the tranny,?? sounds like perhaps it ( tranny ) is still loaded when you try to shift and since it started to do it after a few months of driving, could be bad fluid, master cylinder, or the slave cylinder. I have had similar problems with a Ford that I put a new clutch and disk in. had to bleed it all out and keep runnning new fluid in it till it ran clear again. I use a one man brake bleeder with the pump and if all else fails get a friend to pump clutch while you crack bleeder
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germansupplyscott
- Posts: 887
- Joined: Fri Jul 20, 2001 12:01 am
trans gets stuck in 3rd
vwkurt,
the adjustment procedure is in the bentley manual, i think. but really, all you need to do is loosen the bolts on the engine carrier to frame (ones in the slotted holes), and the two nuts on the front mount (properly called the bump stop). the bump stop mount can move vertically, the carrier can move front to rear. then make sure the carrier is exactly 90deg to the frame and parallel to the engine case, and that the motor is horizontal and in line with the shift rod. you can check shift rod alignment by disconnecting the rear linkage cage and you can see if there is any pushing (up, down or sideways) required to make the linkage line up with the trans gear selector shaft. the main shift rod cannot move about its true center point, not much anyhow, without actually flexing. it should line up with the trans selector with no flexing at all.
yes, and lose the non-stock shift lever, at least until you sort things out.
the fact that it started after a while might point to the motor shifting on its mounts and causing the problem. lets hope so, since that is easy to fix.
also, i forgot that your clutch is hydraulic, so the post above sounds plausible, too
scott lyons
[This message has been edited by punkinfair (edited 01-18-2002).]
the adjustment procedure is in the bentley manual, i think. but really, all you need to do is loosen the bolts on the engine carrier to frame (ones in the slotted holes), and the two nuts on the front mount (properly called the bump stop). the bump stop mount can move vertically, the carrier can move front to rear. then make sure the carrier is exactly 90deg to the frame and parallel to the engine case, and that the motor is horizontal and in line with the shift rod. you can check shift rod alignment by disconnecting the rear linkage cage and you can see if there is any pushing (up, down or sideways) required to make the linkage line up with the trans gear selector shaft. the main shift rod cannot move about its true center point, not much anyhow, without actually flexing. it should line up with the trans selector with no flexing at all.
yes, and lose the non-stock shift lever, at least until you sort things out.
the fact that it started after a while might point to the motor shifting on its mounts and causing the problem. lets hope so, since that is easy to fix.
also, i forgot that your clutch is hydraulic, so the post above sounds plausible, too
scott lyons
[This message has been edited by punkinfair (edited 01-18-2002).]