4+3 Shifting Problems
Thread Starter
Burning Brakes
Joined: Sep 2006
Posts: 1,202
Likes: 3
From: MD
4+3 Shifting Problems
Ok, I've decided to see if the 4+3 will hold up to my new stroker motor, but before I put it all back together I need to check into a problem it was having. My car had trouble shifting. When you tried to put it into gear, especially first, the shifter would get stuck. It didn't grind, it would just stop moving. Other gears did it too, but mostly first at a dead stop. My thoughts on this are that the shifter is worn out. With the trans out of the car, the dog-ears move easily in both directions in and out of gear. I can feel a little sticking in the shifter with the trans out, but I'm not sure what is causing it. Anyone else ever had this problem with a 4+3? Could it simply have been out of adjustment? If so, how do I adjust it?
Melting Slicks
Joined: Feb 2006
Posts: 2,753
Likes: 15
From: backwoods upstate ny
what you specifically described is most often caused by a ''dragging'' clutch ....if the clutch does not fully disengage....could be a clutch disc warped or bent (often bent by 'hanging' the trans unsupported in the disc during trans install/remove) , warped pressure plate. twisted trans input shaft, clutch linkage problem
Burning Brakes
Joined: Jul 2004
Posts: 806
Likes: 0
From: Langley B.C.
Originally Posted by redrose
what you specifically described is most often caused by a ''dragging'' clutch ....if the clutch does not fully disengage....could be a clutch disc warped or bent (often bent by 'hanging' the trans unsupported in the disc during trans install/remove) , warped pressure plate. twisted trans input shaft, clutch linkage problem
Thread Starter
Burning Brakes
Joined: Sep 2006
Posts: 1,202
Likes: 3
From: MD
Interesting. I would have thought that a clutch problem would cause grinding. Anyway, since my new 383 has to be externally balanced I'm getting a new flywheel, clutch disc, pressure plate, pilot bushing, etc. I'm also taking this opportunity to rebuild my clutch slave and master and replace the line. The only thing I'm not sure of is the trans input shaft. How would I check that?
Also, correct me if I'm wrong, but the clutch is self-adjusting, right?
Also, correct me if I'm wrong, but the clutch is self-adjusting, right?
Thread Starter
Burning Brakes
Joined: Sep 2006
Posts: 1,202
Likes: 3
From: MD
I was just remembering taking the enigne apart and thought maybe this was important too (probably should have included it at the beginning). When I removed the clutch and flywheel the pilot bushing fell out onto the floor. When I picked it up you could see that it had been spun inside the crank because the outside of the pilot bushing was scored. Could a loose pilot bushing cause my trans problems?
Melting Slicks
Joined: Feb 2006
Posts: 2,753
Likes: 15
From: backwoods upstate ny
Originally Posted by JLeatherman
Interesting. I would have thought that a clutch problem would cause grinding. Anyway, since my new 383 has to be externally balanced I'm getting a new flywheel, clutch disc, pressure plate, pilot bushing, etc. I'm also taking this opportunity to rebuild my clutch slave and master and replace the line. The only thing I'm not sure of is the trans input shaft. How would I check that?
Also, correct me if I'm wrong, but the clutch is self-adjusting, right?
Also, correct me if I'm wrong, but the clutch is self-adjusting, right?
the clutch is self adjusting unless someone has added the wrong fluid to the master and the mix created a precipitate which interferes with the operations, or if road grit at the pivot points or end of the fork causes excessive friction or worn ''ridges'' to appear.
a loose pilot bearing might be the culprit, might allow the trans input shaft to run out of true and angle the disc....or the input shaft may have excessive run-out which killed the pilot bushing...i would support the end of the input shaft with a vee-block and dial indicate it at its center while turning the trans output by hand...don't have actual specs for max allowable run-out, but would expect .002'' max
Last edited by redrose; Nov 22, 2006 at 05:10 PM.
Thread Starter
Burning Brakes
Joined: Sep 2006
Posts: 1,202
Likes: 3
From: MD
I'll check the run-out of the input shaft at the end and the middle out of curiosity. The bushing wasn't egged out or enlarged from the inside. It was spun in the same way a main bearing gets spun when it's over-revved or something. I'm not actually sure how it happened, but I'm hoping it's the culprit. I've got new everything, even the crank, so when I finally get the car back together I'm hoping this is gone. What, praytell, could possibly cause an input shaft to bend or twist?
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Melting Slicks
Joined: Feb 2006
Posts: 2,753
Likes: 15
From: backwoods upstate ny
Originally Posted by JLeatherman
What, praytell, could possibly cause an input shaft to bend or twist?
Thread Starter
Burning Brakes
Joined: Sep 2006
Posts: 1,202
Likes: 3
From: MD
Interesting. I asked my Dad and he offered an idea. The car sat, unstarted for over 4 years. He believes that a small amount of rust may have accumulated on the input shaft and frozen the pilot bushing onto the shaft. When the car was finally gotten running again the pilot bushing spun in the end of the crank until it broke free, which caused the slop I found in the bushing and ultimately caused the shifting problem. Sound plausible?
Melting Slicks
Joined: Feb 2006
Posts: 2,753
Likes: 15
From: backwoods upstate ny
rust could cause that....the pilot bushing is ''oil-lite bronze'', which is the original ''powdered metal'' manufacturing process but mixed with oil in the metal powder before being compressed--oil should leach out and reduce rusting, but could be another theory bites the dust....i have seen many loose pilot bearings upon disassembly of daily driven cars, do not consider it an unusual failure --i routinely check bellhousing alignments both ways, visual inspect everything else, install new ''wear'' items and have been fortunate to have no problems.
new factor is the 4-year hibernation (news to me at least)....corrosion of flywheel face or many other places could easily cause clutch drag...internal pitting (corrosion damage) of master and slave clutch cylinders is possible, resulting in premature pressure plate release, inspection required
new factor is the 4-year hibernation (news to me at least)....corrosion of flywheel face or many other places could easily cause clutch drag...internal pitting (corrosion damage) of master and slave clutch cylinders is possible, resulting in premature pressure plate release, inspection required
Le Mans Master
Joined: Jul 2001
Posts: 6,252
Likes: 2
From: Silicon Valley Kalifornia
Make sure the shifter is adjusted properly. Inside the tunnel, accessed from inside the car you will be able to adjust it. This is the tool you will need to adjust it in neutral:
Thread Starter
Burning Brakes
Joined: Sep 2006
Posts: 1,202
Likes: 3
From: MD
I can machine that at school this week. Do you have any links to instructions on how to adjust the shifter? I'm intending to buy and install a short-shift kit while I'm at it, so the adjustment will be totally off. What size is that square hole (or doesn't it matter)? Is this adjustment different than the adjustment to the rods?
Instructor
Joined: Dec 2005
Posts: 141
Likes: 0
From: SoCal California
Does not matter the size of the square hole. It is only a key. If you haven't already, look under your carpet under the driver's side. That is where I found my key. The key holds the shifter in what I would call a "true" nuetral position.
Adjustments are made from under the car by adjusting nuts on the linkage rods.
Adjustments are made from under the car by adjusting nuts on the linkage rods.
Racer
Joined: Jan 2004
Posts: 428
Likes: 2
From: Everfrost Second Life
First off....
The 4 plus 3 shifter wears at the bias point. Look at your shifter body. You will have a tack welded adjustment nut. This piece adjusts the reverse lock out rod so that it aligns correctly at the end of the 1-2 gate.
Once adjusted the set bolt is tact welded into place.
THE PROBLEM. The reverse rod WEARS. So now when you pull all the way over into first, sometimes you are grabbing the reverse gate. This gives a funky feel to the shifter.
FIX: If the rod isn't completely worn, grind the weld and make a new ajustement bolt to correctly move the rod in to compensate for wear.
In regards to clutch release issues.... I had written a whole piece on this at the FAQ section of http://www.5speeds.com/board.html
The 4 plus 3 shifter wears at the bias point. Look at your shifter body. You will have a tack welded adjustment nut. This piece adjusts the reverse lock out rod so that it aligns correctly at the end of the 1-2 gate.
Once adjusted the set bolt is tact welded into place.
THE PROBLEM. The reverse rod WEARS. So now when you pull all the way over into first, sometimes you are grabbing the reverse gate. This gives a funky feel to the shifter.
FIX: If the rod isn't completely worn, grind the weld and make a new ajustement bolt to correctly move the rod in to compensate for wear.
In regards to clutch release issues.... I had written a whole piece on this at the FAQ section of http://www.5speeds.com/board.html
Advanced
Joined: Jul 2004
Posts: 68
Likes: 13
From: Topeka, Kansas
I posted a question related to this in General Discussion and was referred here. Your input was helpful. My problem turned out to be the master and slave hydraulic cylenders needed to be rebuilt. I had that done ($650) and everything is fine now except my bank account. The clutch itself and the transmission are OK.
Hope this will be helpful to someone.
Hope this will be helpful to someone.
Team Owner
Joined: May 2002
Posts: 24,337
Likes: 25
From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Another possible way to spin the pilot is if it wasn't installed all the way and the input shaft was jammed into it and spun it when it was first started. There's usually a good 1/4" clearance though between it and the splines on the input shaft.
I would not disassemble the interior to align the shifter. I tried using a machined piece like shown, but it still wasn't right. That would work perfectly for a new shifter, but the edges of the shift gates will wear unevenly, especially if it has been out of alignment for awhile.
You have to fine tune it by feel. When moving side to side, the shifter will want to snag some of the gates. If it's catching the front of a gate, you can move that gate forward by adjusting the shift rod backwards slightly. There is a gate between 1-3 and 2-4 I believe, that doesn't move, so you have to line them up with this first. Some of the gates are slightly wider than others.
If the bushings on the back of the shift rods are shot, aligning the shifter will be a waste of time.
I would not disassemble the interior to align the shifter. I tried using a machined piece like shown, but it still wasn't right. That would work perfectly for a new shifter, but the edges of the shift gates will wear unevenly, especially if it has been out of alignment for awhile.
You have to fine tune it by feel. When moving side to side, the shifter will want to snag some of the gates. If it's catching the front of a gate, you can move that gate forward by adjusting the shift rod backwards slightly. There is a gate between 1-3 and 2-4 I believe, that doesn't move, so you have to line them up with this first. Some of the gates are slightly wider than others.
If the bushings on the back of the shift rods are shot, aligning the shifter will be a waste of time.
