Shifting Malfunction

Moderators: Sluggo, Amskeptic

Post Reply
User avatar
Ronin10
Getting Hooked!
Location: Columbia City, Seattle, WA
Status: Offline

Shifting Malfunction

Post by Ronin10 » Thu Oct 02, 2014 9:51 pm

BACKGROUND:
So back at the beginning of August, Colin and I installed a rebuilt transaxle into my bus. I haven't had the time to really wrap my head around the inner workings of transaxles, but it never seemed quite right. There was always a bit of a "soft wall" when shifting into first and the shift lever kept popping out of gear, particularly first and third, occasionally fourth. I adjusted the stop plate and was able to eliminate the popping out of third and fourth, but never first. I called up my rebuild guy and arranged to have him drive it. He agreed to replace 1st gear with a new gear even though it had passed inspection during the rebuild.

After reinstalling the transaxle, the "wall" to first gear still existing but there wasn't any popping out of any of the gears. Progress.

Yesterday, my son (who has been driving the bus to school lately) informed me that he couldn't get it into first gear and had to start from second gear in order to get home. Fortunately, I was already taking today off of work so I took it out for an extended drive, experimenting and trying to unlock this mystery of no first gear.

SYMPTOMS:
The "wall" to first still exists, but as before, you can push through it and get the same feel of shifting into first as before. Upon releasing he clutch however, first gear grinds.

A simultaneous issue arose that my son hadn't discovered. I can shift into reverse just fine, but when letting out the clutch, it is noticeably rougher than before. And then when trying to shift out of reverse, it's very difficult to disengage, requiring an inappropriate amount of force (and explitives).

ACTIONS SO FAR:
One of the things I felt was off previously during my reinstall was the fore/aft position of the engine/transaxle combo. The forward edge of the forks at the forward transaxle mount/limiting stop were flush with the forward edge of the limiting stop block. Previously, they extended 1/2 - 3/4 inch further forward of the limiting stop. Hoping it might have an impact on this issue, I loosened the two bolts holding the limiting stop, the two on the transaxle carrier, and the four on the engine bearer. I jacked the engine/transaxle up a bit to take the load off and wiggled the engine forward until it match the prior installation position and tightened everything up. Not unsurprising, but no change. Still grinding in 1st gear upon clutch release and reverse is still a bear to disengage.

I have a phone call into the rebuild guy for his feedback, but thought I'd check with the IAC crowd to help isolate the source of this problem.

Off to do some research. Thanks in advance for any insight and guidance you can offer.
Oscar: 1976 Sage Green Bus, Stock Motor, Solid Lifters, Manual Transaxle

User avatar
Amskeptic
IAC "Help Desk"
IAC "Help Desk"
Status: Offline

Re: Shifting Malfunction

Post by Amskeptic » Sat Oct 04, 2014 5:02 am

Ronin10 wrote:BACKGROUND:
rebuilt transaxle kept popping out of gear, particularly first and third, occasionally fourth. rebuild guy agreed to replace 1st gear with a new gear even though it had passed inspection during the rebuild.

The "wall" to first still exists, but as before, you can push through it and get the same feel of shifting into first as before. Upon releasing he clutch however, first gear grinds.

I can shift into reverse just fine, but when letting out the clutch, it is noticeably rougher than before. And then when trying to shift out of reverse, it's very difficult to disengage, requiring an inappropriate amount of force (and explitives).

thought I'd check with the IAC crowd to help isolate the source of this problem.
The wall is called "synchronizers doing their work". That wall should not be there when you shift with the engine off and clutch in.
You cannot downshift into 1st at anything but a crawl or stopped, unless you double-clutch.

Have you and your son been using "force" on the shifter? Not allowed. Stuff gets damaged.
The clutch does release fully, yes? As in, shifting into reverse is quiet, yes?

What is "rougher" in reverse? The sound of the straight-cut gears?
Getting out of reverse should be easy, they are straight-cut gears . . . !

Check the square shift coupler at the front of the transaxle for any evidence that it is slipping between the collar and the cage. It is a cheap swege. Also check that the square bushings are not sloppy. If they are, replace the square coupler, then readjust the stop plate.

If you still have symptoms after you have determined that the clutch is not sticking and the stop plate and coupler are behaving, you will need to go over this with your rebuilder again. He is likely going to be resistant, but you deserve a functional transmission.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

User avatar
Ronin10
Getting Hooked!
Location: Columbia City, Seattle, WA
Status: Offline

Re: Shifting Malfunction

Post by Ronin10 » Sat Oct 04, 2014 9:41 am

To clarify, it takes firmness to get it into first, but we're not slamming it into gear. Previously, sometimes it would seem to be into first gear and upon acceleration, you could hear and feel a small pop as it settled into gear. Sounds to me like further evidence for the synchros not functioning correctly.

On the reverse issue, by rougher I mean that the vehicle initially drives like it still has the parking brake on. It's spotty, doesn't happen all the time and once your speed gets up above a crawl, it smooths out. Could be the clutch sticking, but I'm not seeing it in other gears.

I went out last night and did some further inspection of the shift linkage. I pulled the set screw for the shift linkage. It didn't seem out of order, but I reset it anyway. The rest of the shift coupler is in good order. All buttoned back up and no difference in performance.

I also pulled the boots off either end of the shift rod tube. The rear bushing was there, but the forward one seems to be missing. Since it looks like I'm going to have to pull the engine/trans again, I'll get that in then, but really, nothing in this issues seems like it would be affected by the absence of the bushing.

Going to call the rebuilder again after breakfast.
Oscar: 1976 Sage Green Bus, Stock Motor, Solid Lifters, Manual Transaxle

User avatar
Ronin10
Getting Hooked!
Location: Columbia City, Seattle, WA
Status: Offline

Re: Shifting Malfunction

Post by Ronin10 » Sun Oct 05, 2014 9:05 pm

Went over to the rebuilder today and we tore down the transaxle together. Well, he tore it down and gave me a mini education in VW transaxles. It was really helpful in minimizing the black box perspective.

I still have to install the trans and confirm, but we did find the adjustment of the fork on the 1/2 operating sleeve was out of adjustment. It would not fully seat into first, hence the grinding on clutch release. Tomorrow night is about reinstallation so I should be able to give a test drive evaluation then.

On a side note, I've gotten pretty good at dropping the engine/trans in short order, having it done it about 3-4 in the past few months.
Oscar: 1976 Sage Green Bus, Stock Motor, Solid Lifters, Manual Transaxle

User avatar
asiab3
IAC Addict!
Location: San Diego, CA
Contact:
Status: Offline

Re: Shifting Malfunction

Post by asiab3 » Sun Oct 05, 2014 9:53 pm

That's so great that he let you anywhere near the shop while he did that. And the education aspect- yes!

I hope the adjustment cures your issue.

Robbie
1969 bus, "Buddy."
145k miles with me.
322k miles on Earth.

User avatar
Amskeptic
IAC "Help Desk"
IAC "Help Desk"
Status: Offline

Re: Shifting Malfunction

Post by Amskeptic » Mon Oct 06, 2014 7:03 am

asiab3 wrote:That's so great that he let you anywhere near the shop while he did that. And the education aspect- yes!

I hope the adjustment cures your issue.

Robbie
Man, I would love to be there for something like that.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

User avatar
Ronin10
Getting Hooked!
Location: Columbia City, Seattle, WA
Status: Offline

Re: Shifting Malfunction

Post by Ronin10 » Mon Oct 06, 2014 10:13 pm

The time spent with the rebuilder was very beneficial. It's one thing to read about the function of the synchros, interaction between the different gear stacks, etc. And a whole other thing to see it in action. He even had a trans body with a section cut away to show the shifting action in effect.

Tonight , I installed the engine and trans (first time without any kind of guide or walkthrough close at hand). I also replaced the shift rod bushings because one had gone all pear shaped. End result...drives wonderfully.

On to the next task. Thanks for the guidance!
Oscar: 1976 Sage Green Bus, Stock Motor, Solid Lifters, Manual Transaxle

User avatar
Amskeptic
IAC "Help Desk"
IAC "Help Desk"
Status: Offline

Re: Shifting Malfunction

Post by Amskeptic » Tue Oct 07, 2014 1:15 pm

Ronin10 wrote:The time spent with the rebuilder was very beneficial. It's one thing to read about the function of the synchros, interaction between the different gear stacks, etc. And a whole other thing to see it in action. He even had a trans body with a section cut away to show the shifting action in effect.

Tonight , I installed the engine and trans (first time without any kind of guide or walkthrough close at hand). I also replaced the shift rod bushings because one had gone all pear shaped. End result...drives wonderfully.

On to the next task. Thanks for the guidance!
Glad to hear it got resolved.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

User avatar
Bleyseng
IAC Addict!
Location: Seattle again
Contact:
Status: Offline

Re: Shifting Malfunction

Post by Bleyseng » Wed Oct 08, 2014 6:48 am

Who was the transmission rebuilder? Local?
Geoff
77 Sage Green Westy- CS 2.0L-160,000 miles
70 Ghia vert, black, stock 1600SP,- 139,000 miles,
76 914 2.1L-Nepal Orange- 160,000+ miles
http://bleysengaway.blogspot.com/

User avatar
Ronin10
Getting Hooked!
Location: Columbia City, Seattle, WA
Status: Offline

Re: Shifting Malfunction

Post by Ronin10 » Fri Oct 10, 2014 7:28 am

Yeah, local. As in not even 5 miles from my house on the south side of Lake Youngs. Gary's Transaxles. Gary's an old retired Boeing guy and does this as a part time for years and years and years. He only does the older manual transaxles for VWs and Porsches. I was referred to him by a couple of the local ACVW shops. Very helpful guy and more than willing to make things right. Given that I work in Everett, but live in North Kent/Renton, it was helpful to be able to work with him in the late afternoons, early evenings, and weekends.
Oscar: 1976 Sage Green Bus, Stock Motor, Solid Lifters, Manual Transaxle

Post Reply