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> May have found my transmission problem?
914bub
post Oct 11 2017, 12:01 AM
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I have had a shifting problem since I got my 914 almost 4 years ago. When I got the car the clutch was toast so I replaced all the clutch related parts, including the flywheel. Once I got the car driving I realized it wouldn't go into first gear. I speculated that first gear had gone out and the previous owner had driven starting out in second, finishing off the clutch. The car had been parked since 1990 and the PO is deceased so it was just a guess.

The ball bushing at the base of the shifter was destroyed so I ordered a shifter bushing kit and replaced that bushing as well as,(if I remember correctly) the two ball bushings at the firewall.The car would grind and grind but wouldn't go into first gear. After reading a bunch of threads here I decided to pull the nose cone and replaced first gear and syncho with a marginally better set of parts out of a side-shifted core trans I have here.

Success! So I thought........ First gear worked well for about a week and a half, then back to the same old game. I found it hard to believe I installed parts that literally had a couple weeks of life left in them.

I pulled the pedal assembly out about a year ago and then got busy playing with motorcycles. I finally got it back together and in this week.( I rebuilt it not because I thought it would solve my first gear problem but it just needed it).After getting everything together I was looking at the linkage trying to see anything awry and I found this:

Attached Image

I apologize for the washed out picture but you should be able to see what I'm talking about. The bushing the shift rod goes through has NO play although it is old. The shift rod slides freely through it as well. I loosened the bracket and pryed it so the shift rod was more centered in the linkage coming out of the transmission but it seems like it could go a little higher up and be a little "happier". Sorry I didn't take an after picture, I can tomorrow.

My biggest question is should the end of the shift rod be as "hourglass" shaped as it is or is that all attributable to wear? I can drop the shift rod for a better picture, or if someone has a picture of a "good" one I can compare to? If it is worn our machinist at work can build it up if needed so I can shape it correctly.
I need to put the gas tank back in so I can drive it and see if it's better. Any advice would be greatly appreciated. I apologize for the long post.

The rest of the gears engage fine, I think the shifter adjustment is ok.
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76-914
post Oct 11 2017, 08:13 AM
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Maybe! Or the shift fork has so much resistance the part broke from stress. You'll know a soon as you replace that piece. Let us know. (IMG:style_emoticons/default/beerchug.gif)
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rhodyguy
post Oct 11 2017, 08:22 AM
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Have you ever checked above the inspection/access plate on the rear of the trans? There is a rolled pin that can partially fail.
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914bub
post Oct 11 2017, 08:38 AM
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QUOTE(76-914 @ Oct 11 2017, 07:13 AM) *

Maybe! Or the shift fork has so much resistance the part broke from stress. You'll know a soon as you replace that piece. Let us know. (IMG:style_emoticons/default/beerchug.gif)


"The part"..... Which part?

"That piece".... Which piece?


I'll get this yet. Hopefully, I'll be able to test drive tonight and offer more info. I found pictures of other severely worn shift rods that had a much more hourglass shape than mine. I still don't know if it should be a slight hourglass shape or not at all.


Rhodyguy, I meant to mention I will be checking that tonight. I read a thread about that after I posted last night. I also meant to ask if only side shift cars have cone set screws? I went to check my linkage and found nothing like I saw online. I haven't looked at my side shift linkage as it's packed away right now.

I have a side shift transmission and about 90% of the parts to install it but I didn't want to install it until I "needed to". Maybe I "need to"!
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Racer Chris
post Oct 11 2017, 08:53 AM
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Yes it should have the hourglass shape. The wear points are on the fore/aft surfaces. I've used brass shim stock before, to remove excess free play between those two components. And yes, it looks like it would fit better raised up a little further.
Grinding first is likely not related to the orientation of that area on the linkage though.
Have you checked the clutch tube? If you can eliminate the grinding by adjusting the clutch cable, then you have a problem with the tube or you don't have the cable end double nutted, or the roll pin in the clutch pedal has failed.
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Dr Evil
post Oct 11 2017, 09:24 AM
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100% with Chris.

Its worth unbolting that small square plate at the bottom rear, 4 x 10mm nuts, and checking the rod in there and the roll pin that secures the shifter part of the rod. I actually have a pic of a /6 (same set up) that had the wrong roll pin in there (one layer, not several, think taco vs fruit roll up) that I had to replace. I cant post from here, but can tonight. That shift rod looks fine, just a little low, maybe. For first gear you need ability of it to command the shift rod fully FORWARD, and fully IN. Make sure that nothing is binding this, like the bracket. See what you need to do to the rod to get this actuation to happen. It will guide any adjustments. Check clutch tube like mentioned. Also, if it is grinding AT ALL going into reverse then your clutch is dragging and it will wear out 1st gear as well. HTH (IMG:style_emoticons/default/bye1.gif)
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914bub
post Oct 11 2017, 01:41 PM
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Thanks for all the replies so far. It's definitely not the roll pin at the pedal. The pedal assembly is rebuilt and I had my face up against it last night connecting the clutch cable so I verified that.

I'd like to think that if the roll pin inside was screwed up or loose I would have noticed that with the nose cone off, but stranger things have happened. I'll pull the cover tonight on the trans and have a look.I'm home now for lunch and almost went to tear it apart now but there's too much junk in the way to make it worth the effort, I'll tear into after work.

I did check the linkage at the inspection plate between the seats as I was running out the door this morning. The hardware, as well as the spot welds that hold the front part of the shaft together, are all good. I'm going to double check the balls at the firewall to be sure I replaced them, ( I have 2 spares in my box of parts which I shouldn't have). By clutch tube I assume you mean the metal tube that should be tack welded in the tunnel? I have not looked at that yet. Is a visual inspection all or is there a "test"? I thought I read somewhere about engaging the clutch pedal and watching through the inspection hole?

I'll report back tonight and I'll take all kinds of pictures of crap I don't even think I need pictures of. I learned the hard way recently and have to take another project apart because I didn't pay attention to whether certain parts were updated because at the time it didn't matter. A longer, more stupid story for sure.
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914bub
post Oct 11 2017, 11:35 PM
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Tonight I pulled the inspection cover on the trans. Everything looks great in there. No play between the shaft and the part the roll pin is retaining so I buttoned that back up. I pulled the rear shift rod and replaced the two ball bushings and the rear rod support bushing. The balls were within about a half mm of the old ones so they were worn but not terribly chewed up or falling apart.The rear support bushing is actually a little sloppier than the one I removed. I greased everything. I need to get the rubber boot that covers the shift rod at the rear bushing.

I pettered out as today was long at work. I didn't get the gas tank in so no test drive tonight. I should be able to drive it tomorrow. How do I check the clutch cable tube? Engage the clutch while feeling in the tunnel for movement? If I can figure out how to check it I'll probably run out tonight and check it.

i am currently not running a lock nut on the clutch cable. I looked for one when I did the clutch and couldn't find one but I'll put on an incorrect one for now so I have one. Thanks again for all the guidance and advice.

Pix:
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Racer Chris
post Oct 12 2017, 06:33 AM
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Position of the rod looks good in your last picture.

Two places to look for clutch tube trouble - at the firewall, and in the tunnel to the left of the shift lever. Actuate the clutch and observe if there is movement. The trouble usually starts at the front attachment and then eventually overstresses the firewall.

Jam nut on the cable is critical. The single nut will slowly unscrew itself with each operation of the clutch.
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914bub
post Oct 12 2017, 08:13 AM
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QUOTE(Racer Chris @ Oct 12 2017, 05:33 AM) *

Position of the rod looks good in your last picture.

Two places to look for clutch tube trouble - at the firewall, and in the tunnel to the left of the shift lever. Actuate the clutch and observe if there is movement. The trouble usually starts at the front attachment and then eventually overstresses the firewall.

Jam nut on the cable is critical. The single nut will slowly unscrew itself with each operation of the clutch.


Thank you. I'll check the clutch tube today. I knew I needed a lock nut, I'll get one installed today. I'll have more info tonight. Hopefully good news.
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Dr Evil
post Oct 12 2017, 08:14 AM
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Ya, that looks much better. Agree with jamb not, has to be there or clutch will eventually start to drag and you will wear out internal parts and hate driving.
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Dr Evil
post Oct 12 2017, 01:35 PM
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http://www.914world.com/bbs2/index.php?showtopic=109708

Recently bumped from the dead and very relevant for checking yourself.
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Dave_Darling
post Oct 12 2017, 05:47 PM
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Don't trust Nyloc nuts on the clutch cable. The nylon wears and the clutch will lose adjustment. Double-nut the adjustment; it really is the only way to go.

The nuts are M7, which is an unusual size. Especially on these cars. M8 nuts will fit, but will let go the first time you push the pedal down. They will shoot across the garage and you'll never find them after that. (Voice of experience, there.)

--DD
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914bub
post Oct 13 2017, 01:36 AM
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QUOTE(Dave_Darling @ Oct 12 2017, 04:47 PM) *

Don't trust Nyloc nuts on the clutch cable. The nylon wears and the clutch will lose adjustment. Double-nut the adjustment; it really is the only way to go.

The nuts are M7, which is an unusual size. Especially on these cars. M8 nuts will fit, but will let go the first time you push the pedal down. They will shoot across the garage and you'll never find them after that. (Voice of experience, there.)

--DD


Dave, thank you, double nut was the plan. 7 X 1.0 ? I think I can get one even though it's such an oddball size. Reminds me of working on PRV engines in Volvos and DeLoreans. I planned on getting the gas tank in tonight but an ill family member sidetracked the night. Tomorrow night I should finally get to the point of a test drive. I'll call in the morning and see if I can get the nut at lunch. Pacific Bolt has come through with some pretty weird stuff. Fingers crossed.....
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Tbrown4x4
post Oct 13 2017, 02:44 AM
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914 rubber has the nuts
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914bub
post Oct 20 2017, 12:15 AM
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I'm adding a final post,not because I think anyone is fascinated with the thread, but because I can't stand finding old threads and reading them, only to find they were never resolved. I didn't fix my first gear problem and I'm throwing in the towel.

I verified that the clutch tube isn't loose and double nutted and readjusted the clutch. I found an old 914world thread that said rocker arm shaft retaining nuts are the same as the clutch adjusting nuts. Thanks to Mr Mueller I had one of those.

After all that I still couldn't get first gear so I adjusted the clutch even tighter. Too tight in fact as I wanted to see if it would go into first that way,.....nope. I still find it hard to believe that I installed a used first gear that only had a few minutes of life left in it but apparently that's the case. I really wanted to get this resolved. I was planning on the side shift conversion but I wanted to know if I had a good used tail shifted trans for a potential future 914. I also only have MOST of the conversion parts.

One question I had about the conversion was shifter adjustment. I've read a lot about it and what I was wondering is where do you start at "ground zero" when doing the conversion? The threads I read said to mark your linkage with a sharpie before starting so you know where you started. Do I just assemble the shifter linkage with everything about 50% if that makes sense? In other words, assemble everything set about "in the middle" or the ramge of adjustment and go from there?
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Old Yella
post Oct 20 2017, 03:48 AM
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Did you check the pedal stop is allowing the correct travel.



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Racer Chris
post Oct 20 2017, 06:27 AM
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QUOTE(914bub @ Oct 11 2017, 02:01 AM) *

After reading a bunch of threads here I decided to pull the nose cone and replaced first gear and syncho with a marginally better set of parts out of a side-shifted core trans I have here.

Did you replace the slider?
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914bub
post Oct 20 2017, 08:18 AM
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QUOTE(Racer Chris @ Oct 20 2017, 05:27 AM) *

QUOTE(914bub @ Oct 11 2017, 02:01 AM) *

After reading a bunch of threads here I decided to pull the nose cone and replaced first gear and syncho with a marginally better set of parts out of a side-shifted core trans I have here.

Did you replace the slider?

Yes, I did, however, it was used. I will double check pedal stop. If it never worked I'd feel a whole lot better and like I wasn't missing anything. It's the fact that it worked for a short time that has me pulling my hair out.
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Dr Evil
post Oct 20 2017, 01:02 PM
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Just to be thorough, ground strap in place? If not the cable becomes the ground and erodes/stretches until it breaks.

However, your question about shifter adjustment makes me think that there may be your issue. Read my 31 pages of notes link below, it has a shifter and clutch adjustment section for how I do it. Racer Chris has another method that is different than mine, but is also tried and true. Check that stuff and get back to us.

FYI, most tail shifters are really roached and not great for conversion. However, I have everything you need inside and out so you are not totally boned. Really just not optimal, but still workable.
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