Problem with 2nd Gear Grinding Options

[RMWorks]

Hi All - got a 1975 with side shift. 2nd gear is grinding primarily on downshifts and hoping to get some direction for best next steps. Here’s the backstory:

When I bought car 18 months ago the shifting was pretty vague but all the gears were there and no grinding on anything except very occasionally on downshifts into 1st while still rolling (pretty much normal for 914, right?).

Info from previous owner suggests transmission was replaced under his ownership with rebuilt unit - and if true, that means less than 1000 miles on it.

Early this summer, took the car out one day and all of a sudden 2nd gear was grinding on both upshifts and downshifts. Though it seemed more likely to grind on downshift, it would always grind on quicker upshifts as well.

Over the next couple of months I had the following done:

-transmission drained & refilled
-all main points of shift linkage checked for integrity
-replaced worn (loose and disintegrating) bushings
-checked cone screws
-found crown bushing hole in shift console was worn quite large and had developed significant play - had that fixed by welding part and sizing new opening for bushing… replaced seal/gasket and re-installed

Result is that shifting is much improved and vagueness all but gone. The car shifts quite nicely now with positive throws into each gear almost all the time.

Although I did not get a ton of road time following the repairs listed above (before putting it into winter storage), it grinds badly on downshifts into 2nd every time now (actually a little worse than before). It grinds a tiny bit on upshift into 2nd but ONLY if you shift quickly from 1st to 2nd - and only a tiny bit. If you upshift at ‘normal’ or leisurely speed from 1st to 2nd there is no problem at all. In the 20 or so miles I drove, I detected a slight grind on upshift from 2nd to 3rd once. No problem with any other gears.

Rev-matching downshift into 2nd makes no difference - still grinds. Double-clutching also makes no difference - still grinds.

I am no expert here by any means, but doesn’t the fact that it still grinds even with double-clutching mean it’s likely not a bad synchro? I also feel like the grinding on upshifts went almost completely away with the linkage improvements, so that maybe points to it not being a synchro issue..? Also thinking that the suddenness of the initial problem cropping up was more to do with linkage than a bad synchro or bad gear - which presumably would have gotten progressively bad/worse over time.

The whole shift pattern is not off to the point there’s trouble finding the gears… but could there still be some adjustment needed that would account for this 2nd gear problem?

Anything else I’m not thinking of? I consider a rebuild the last resort and based on PO’s info should not be necessary. I have heard though that you can replace 1st gear & synchro without removing the whole tranny from the car… is it likewise possible to do 2nd gear that way if necessary (wishful thinking?)?

Thanks for reading,
Dave

[brant]

The common (and inaccurate) statement about “worn synchros” on these cars is really a misleads statement

Synchros can and do wear
But the “slider” inside the transmission sounds like your actual problem
It’s an expensive part
And it’s very common for the slider to be damage and mistakenly be called a bad “synchro”

My guess is your 1st gear slider is shot
Pulling the gear stack (opening the transmission) is the only way to be sure and to fix the problem

It’s around a 500 part unfortunately

[johnhora]

Other things to review...
What's the age of the clutch and pressure plate?
How's the clutch cable/pedal package...is it adjusted correctly?

[RMWorks]

Thanks, Brant. Sounds like a definitely possibility. Wish I knew the condition of the rest of the gearbox without tearing into it so I had a better sense of whether or not to just look for a whole new box.

Will explore any other simpler & cheaper things first I guess.

The common (and inaccurate) statement about “worn synchros” on these cars is really a misleads statement

Synchros can and do wear
But the “slider” inside the transmission sounds like your actual problem
It’s an expensive part
And it’s very common for the slider to be damage and mistakenly be called a bad “synchro”

My guess is your 1st gear slider is shot
Pulling the gear stack (opening the transmission) is the only way to be sure and to fix the problem

It’s around a 500 part unfortunately

[RMWorks]

Did not inherit full service records but the clutch feels great and seems to be adjusted correctly. No visible signs that cable is out of adjustment or damaged at all. I haven't had a mechanic really look into that closely because I figured if it's not happening equally in other gears it really shouldn't be clutch related... but could be wrong about that..?

Other things to review...
What's the age of the clutch and pressure plate?
How's the clutch cable/pedal package...is it adjusted correctly?

[rhodyguy]

Is the clutch cable double nuted?

[Rand]

I trust Brant's experience. But dang if that doesn't sound like a synchro. Second gear is the puzzler though. It's usually going into first, and then downshifting to 3rd first helps. Please share the solution when you find it.

[yeahmag]

I love Brant, but I think based solely on your description it's either a worn 2nd gear syncro or an adjustment issue (and you're nicking reverse). So here are a couple of tests to run:

* Does reverse gear grind? This test needs to be done with the engine running and the car not moving. This will test the clutch adjustment. If it does, adjust the clutch. If not, move on.

* Try adjusting the shifter a bit. We are looking for a problem with selecting 2nd. Specifically nicking reverse. With the engine off, put the car in 2nd gear and make sure the stick is dead center and forward. At this point we aren't too worried about anything other than R-1-2, so take it for a drive and see if anything has changed.

* If you are indeed rev matching and/or double clutching properly (there is a technique) even with no synchronization in effect you can get a pretty good shift. If you don't do this all the time or haven't had somebody teach you, I'd guess you are doing it wrong. One way to test this is to not use the clutch to engage the gear. Odds are this is a red herring...

Let us know what you find.

[RMWorks]

I figured it might not be synchro since it came on so suddenly, but as I'll address in reply to yeahmag I may also not be properly double-clutching... so maybe it still is just that. I've read that 1st gear synchro can be replaced without pulling the whole tranny out of the car... wonder if you could pull enough of the stack out to do 2nd that way too (wishful thinking probably).

Thanks for the reply.

I trust Brant's experience. But dang if that doesn't sound like a synchro. Second gear is the puzzler though. It's usually going into first, and then downshifting to 3rd first helps. Please share the solution when you find it.

[RMWorks]

As far as I can recall I've had no grinding going into reverse.

I was really hoping it might be just a shifter adjustment, but was thinking the whole pattern would be off if that was the case...? And therefore would grind pretty much everywhere. I may just be showing my lack of knowledge here though.

I can appreciate the red herring comment since I will freely admit I may not know how to properly double-clutch. I honestly didn't think there was anything more to it than shifting to neutral in between clutching out of one gear and then clutching into the next... so sounds like more lack of knowledge on my part.

I am going to find out all I can about adjusting the shifter & shift pattern and make that the priority - sounds like the easiest and least expensive option so fingers-crossed.

Thank you very much for the info.

I love Brant, but I think based solely on your description it's either a worn 2nd gear syncro or an adjustment issue (and you're nicking reverse). So here are a couple of tests to run:

* Does reverse gear grind? This test needs to be done with the engine running and the car not moving. This will test the clutch adjustment. If it does, adjust the clutch. If not, move on.

* Try adjusting the shifter a bit. We are looking for a problem with selecting 2nd. Specifically nicking reverse. With the engine off, put the car in 2nd gear and make sure the stick is dead center and forward. At this point we aren't too worried about anything other than R-1-2, so take it for a drive and see if anything has changed.

* If you are indeed rev matching and/or double clutching properly (there is a technique) even with no synchronization in effect you can get a pretty good shift. If you don't do this all the time or haven't had somebody teach you, I'd guess you are doing it wrong. One way to test this is to not use the clutch to engage the gear. Odds are this is a red herring...

Let us know what you find.

[RMWorks]

Thread is pretty old now but just circling back to thank everyone for their input. After making a bunch of adjustments, took the car to transmission shop and ended up getting it partially rebuilt. Still needs some fine adjustment, but no more grinding.

[vitamin914]

Thread is pretty old now but just circling back to thank everyone for their input. After making a bunch of adjustments, took the car to transmission shop and ended up getting it partially rebuilt. Still needs some fine adjustment, but no more grinding.

The thread may be old but... but the help it gives is timeless.

I seem to have exactly what yeahmag describes in his point 2.

In my 74, the individual gears do not grind, but sometimes 1st is hard to engage. My biggest problem is the shift from 1st to 2nd. It is very easy to nick reverse going for second. That grinding sound may as well be a 100000 volt shock though the shift knob it is so horrible. I thought there may have been a weak spring making the shift towards reverse too easy.

Does anyone have some recommendations on the procedure how to adjust the shifter a bit to solve too easy touching of the reverse gear? This is something I have never done.

[Chaznaster]

Thread is pretty old now but just circling back to thank everyone for their input. After making a bunch of adjustments, took the car to transmission shop and ended up getting it partially rebuilt. Still needs some fine adjustment, but no more grinding.

The thread may be old but... but the help it gives is timeless.

I seem to have exactly what yeahmag describes in his point 2.

In my 74, the individual gears do not grind, but sometimes 1st is hard to engage. My biggest problem is the shift from 1st to 2nd. It is very easy to nick reverse going for second. That grinding sound may as well be a 100000 volt shock though the shift knob it is so horrible. I thought there may have been a weak spring making the shift towards reverse too easy.

Does anyone have some recommendations on the procedure how to adjust the shifter a bit to solve too easy touching of the reverse gear? This is something I have never done.

I found this string helpful. If I recall there are other links embedded with additional information. Although I’d recommend checking your linkage bushings if they have not already been replaced.
http://www.914world.com/bbs2/index.php?showtopic=188120

[windforfun]

Have you replaced the bushing in the firewall? BTDT.

[vitamin914]

Have you replaced the bushing in the firewall? BTDT.

No - I have not checked that yet - but will. There is a lot great information for me to go through in these threads. Plenty of tips and tricks to learn. Working on this for the first time will be a bit scary. My biggest fear is screwing something up and making things worse rather than better.

[930cabman]

Cheapest/easiest is checking the clutch engagement. How is your free play at the pedal?