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> 1975 914 1st gear jumping out issue
ndfrigi
post Nov 4 2011, 12:39 PM
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Hi 914's owner! I have 75' 2.0 914 and I'm having a problem with my 1st gear. It jump out upon releasing the clutch. I already replaced all the shift bushings but when I push down to 1st gear and while releasing my clutch, there you go it jump out or grinding from the gear happens. Any suggestions on how to fix it? thank you and God Bless!


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jimkelly
post Nov 4 2011, 01:05 PM
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your issue could be in here?

ignore that in pic - 1st gear of blocked off : )

your 1st gear dogteeth could be toast, or your 1st gear/reverse slider could be toast, or both could be toast.



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ndfrigi
post Nov 4 2011, 01:09 PM
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QUOTE(jimkelly @ Nov 4 2011, 12:05 PM) *

your issue could be in here?

ignore that in pic - 1st gear of blocked off : )

your 1st gear dogteeth could be toast, or your 1st gear/reverse slider could be toast, or both could be toast.


Is this image part of the transmission at the end part? where you will be able to see it when you removed the gear shifter? thanks!
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poorsche914
post Nov 4 2011, 01:22 PM
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Is your linkage adjusted correctly?
Could be not enough movement to engage first gear completely.
Are you able to engage 3rd and 5th gears?

(IMG:style_emoticons/default/driving.gif)
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ndfrigi
post Nov 4 2011, 01:26 PM
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QUOTE(poorsche914 @ Nov 4 2011, 12:22 PM) *

Is your linkage adjusted correctly?
Could be not enough movement to engage first gear completely.
Are you able to engage 3rd and 5th gears?

(IMG:style_emoticons/default/driving.gif)



Yes, I can shift to 2nd, 3rd, 4th and 5th properly. For the meantime I start with the 2nd gear. Reverse is also doing ok.
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jimkelly
post Nov 4 2011, 01:28 PM
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yes - this pic is what is inside the end cap/cone.

that said - you could remove the linkage from your trans - tie wrap it away - and put trans into 1st gear by hand - and see if you can drive a few feet this way without it popping out.
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underthetire
post Nov 4 2011, 02:03 PM
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Personally I would suspect shifter adjustment as well, especially after doing the bushings.
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ndfrigi
post Nov 4 2011, 02:41 PM
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QUOTE(jimkelly @ Nov 4 2011, 12:28 PM) *

yes - this pic is what is inside the end cap/cone.

that said - you could remove the linkage from your trans - tie wrap it away - and put trans into 1st gear by hand - and see if you can drive a few feet this way without it popping out.


thanks again and I'll try that! God Bless!
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ndfrigi
post Nov 4 2011, 02:42 PM
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QUOTE(underthetire @ Nov 4 2011, 01:03 PM) *

Personally I would suspect shifter adjustment as well, especially after doing the bushings.


thank you!
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Richard Casto
post Nov 4 2011, 03:13 PM
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In short there is a recess that is machined within the syncro hub (that is mounted to the gear) and the associated slider (that moves when you shift gears). That positive feel of engagement you get when you shift into gear is when the hub and slider are becoming 100% engaged. The two recesses are now merged into one single recess and the synchro ring was compressed during the shifting motion has now popped into the merged recess. The force of the syncro ring living in that recess is what keeps the slider and hub engaged (car in gear). To shift out of that gear you get another positive feel of disengagement as you compress the ring to get it out of the recess and then the slider disengages from the hub and you are back into neutral.

So what causes it to pop out of gear? Ultimately there is not enough force keeping the slider and hub engaged. Typical causes would be...

1. Worn hub, slider and/or synchro (items associated with the ring in the recess are worn out an no longer provide the required force to keep engaged).
2. Incorrect adjustment on the shift fork (not able to fully engage 1st so it pops out before it is 100% engaged).
3. Incorrect adjustment on the shift linkage (not able to fully engage 1st so it pops out before it is 100% engaged).

Any are possible. As you say you have problems only with 1st, I tend to think it is most likely #1 and not #2 or #3. If you said you had a problem with 1st, 3rd and 5th, then it would be more likely to be a shift lever adjustment problem.

Depending upon how mechanically inclined you are, you can (as Jim suggested above) shift into first via your lever. Then detach the shift linkage and then double check directly at the linkage on the transmission that it is in first gear and fully engaged. This should remove any questions as to linkage issues. Then see if it pops out of 1st gear when you apply power (drive the car).

If you have narrowed it down to being inside the transmission then I would not use 1st gear until you can get it fixed. The first/reverse slider is a particular costly item and any 1st gear "grinding" is an indication that you are damaging the slider and synchro hub. They may already be worn beyond reuse at this point.

Lastly you mention that reverse work fine. If you had said you also grinding when shifting into reverse, I would say that your clutch is not fully disengaging. But that does not sound like the case.

Sorry about your problems. Let me know if there is anything else I can do to help.

Richard
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ndfrigi
post Nov 4 2011, 03:35 PM
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QUOTE(Richard Casto @ Nov 4 2011, 02:13 PM) *

In short there is a recess that is machined within the syncro hub (that is mounted to the gear) and the associated slider (that moves when you shift gears). That positive feel of engagement you get when you shift into gear is when the hub and slider are becoming 100% engaged. The two recesses are now merged into one single recess and the synchro ring was compressed during the shifting motion has now popped into the merged recess. The force of the syncro ring living in that recess is what keeps the slider and hub engaged (car in gear). To shift out of that gear you get another positive feel of disengagement as you compress the ring to get it out of the recess and then the slider disengages from the hub and you are back into neutral.

So what causes it to pop out of gear? Ultimately there is not enough force keeping the slider and hub engaged. Typical causes would be...

1. Worn hub, slider and/or synchro (items associated with the ring in the recess are worn out an no longer provide the required force to keep engaged).
2. Incorrect adjustment on the shift fork (not able to fully engage 1st so it pops out before it is 100% engaged).
3. Incorrect adjustment on the shift linkage (not able to fully engage 1st so it pops out before it is 100% engaged).

Any are possible. As you say you have problems only with 1st, I tend to think it is most likely #1 and not #2 or #3. If you said you had a problem with 1st, 3rd and 5th, then it would be more likely to be a shift lever adjustment problem.

Depending upon how mechanically inclined you are, you can (as Jim suggested above) shift into first via your lever. Then detach the shift linkage and then double check directly at the linkage on the transmission that it is in first gear and fully engaged. This should remove any questions as to linkage issues. Then see if it pops out of 1st gear when you apply power (drive the car).

If you have narrowed it down to being inside the transmission then I would not use 1st gear until you can get it fixed. The first/reverse slider is a particular costly item and any 1st gear "grinding" is an indication that you are damaging the slider and synchro hub. They may already be worn beyond reuse at this point.

Lastly you mention that reverse work fine. If you had said you also grinding when shifting into reverse, I would say that your clutch is not fully disengaging. But that does not sound like the case.

Sorry about your problems. Let me know if there is anything else I can do to help.

Richard


Wow Thanks Richard! Now I have more idea what to look at. Keep you posted. God Bless!
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ScottD914
post Nov 4 2011, 07:01 PM
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(IMG:style_emoticons/default/idea.gif) Hmm... I would suspect the linkage first. 1st is left and back (pulling your shift ball forward on the transmission).

Try shortening the linkage an 1/8" by loosening the clamp that grips the splined shaft under your shift lever. Re-tighten and give it a try.

Worth a shot and better than tearing into the tranny.
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ndfrigi
post Nov 4 2011, 07:14 PM
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QUOTE(ScottD914 @ Nov 4 2011, 06:01 PM) *

(IMG:style_emoticons/default/idea.gif) Hmm... I would suspect the linkage first. 1st is left and back (pulling your shift ball forward on the transmission).

Try shortening the linkage an 1/8" by loosening the clamp that grips the splined shaft under your shift lever. Re-tighten and give it a try.

Worth a shot and better than tearing into the tranny.


I'll try also what the other guy by shifting it to 1st gear manually and try running it if will not pop up anymore. Thank you!
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Richard Casto
post Nov 5 2011, 11:15 AM
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QUOTE(ScottD914 @ Nov 4 2011, 09:01 PM) *
... and better than tearing into the tranny.

(IMG:style_emoticons/default/confused24.gif) Nobody suggested pulling the transmission apart as step #1. Both Jim and I suggested testing to see if it is linkage/adjustment related first.

Richard
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ndfrigi
post Nov 5 2011, 12:41 PM
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QUOTE(Richard Casto @ Nov 5 2011, 10:15 AM) *

QUOTE(ScottD914 @ Nov 4 2011, 09:01 PM) *
... and better than tearing into the tranny.

(IMG:style_emoticons/default/confused24.gif) Nobody suggested pulling the transmission apart as step #1. Both Jim and I suggested testing to see if it is linkage/adjustment related first.

Richard


Yup I will not do that, actually I just tried this morning to push by hand the shift from the bottom towards the 1st gear position and yes it did not pop up anymore. I tried adjusting the linkage from the bottom of the stick but it did'nt work or should I adjust the linkage from the gear shift (from the tail shift)?

Thanks again and hoping you will help me till I able to correct it.
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underthetire
post Nov 5 2011, 12:59 PM
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You have a side shift in that, not a tail shift. Loosen the pinch clamp between the shifter and firewall, shorten the linkage by a little at a time. It is possible a shifter forkis worn, the shifter fork clamp inside the trans, or the slider piece is off as well.
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flash914
post Nov 5 2011, 04:59 PM
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Send me a email please flash2point@yahoo.com
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Dr Evil
post Nov 5 2011, 09:01 PM
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If it is an adjustment issue, you need it fixed soon as it will cost a lot in parts if it continues. I do fear that it is going to be the parts, though. See the link in my signature for a step by step on what to check.
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