I've tried searching this site for the problem but I've come up empty handed, or I'm just missing it somewhere.
Has anyone ever experienced an issue with reverse coming ("grinding") out of gear when trying to back up? It's strange, if I forcefully hold the shifter in reverse and ride the clutch it helps to some degree before embarrassing me. I've learned to find a parking spot that suits this problem but it make getting it out of the garage a real pain in the butt ritual. Someone mentioned checking the shifter linkage under the rear seat panel? I use to have the problem with it slipping out of 1st but was able to fix that with simply adjusting the shifter location.
Any help would greatly be appreciated.
Thanks guys,
Drew
I think reverse hates me...
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Marc
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- Joined: Thu May 23, 2002 12:01 am
Re: I think reverse hates me...
Very common problem, unfortunately, and there's nothing you can do externally to make it better other than ensuring that the shifter adjustment is allowing full engagement of Reverse/2nd/4th. It probably is, but you can be sure by lifting up the back seat and removing the oval plate over the shift coupler. Watch it work as you run through the gears - parked/engine-off, of course 
The transmission has internal detents for each gear position so as the linkage gets verrrry close to each gear, you can actually see the shaft that comes out of the transmission's nose pull itself into place as the spring-loaded detent ball inside finds home. Further motion of the shifter only makes the internals overshoot their ideal position slightly.
You mentioned previously adjusting the shifter to get more First gear engagement. If you did that without making the check I just described, you may have shortchanged the engagement of Reverse, 2nd, and 4th and shortened your Reverse life expectancy dramatically.
When you are driving in First or Second, romp on and off the throttle and watch the shift knob. Does it move by itself? That's a classic symptom of a loose or shot front transmission mount - if you overadjusted the shifter towards First to compensate, guess what? You are to blame for the present problem.
What's going on inside is that the Reverse sliding gear (the one that moves into place to engage straight-cut teeth on the perimeter of the 1/2 operating sleeve) gets worn, until it's all rounded off and looks smeared. The teeth on the 1/2 slider wear also, but usually not quite as much. As soon as any torque is applied (as you let out the clutch in Reverse) these rounded-over gears simply refuse to stay meshed and the Reverse sliding gear gets "spit out".
It doesn't take an entire transaxle overhaul to "patch" Reverse if the 1/2 slider isn't too bad, but just replacing that little Reverse sliding gear still requires some major surgery, beyond what the average shade-tree mechanic can do...takes some special tools, too, so it's best left to a pro. You can remove the transaxle, and if you feel adventurous the axles too, but I would not advise going much further.
Most folks just start shopping for a better used transmission at this point, and pick their parking spaces carefully to preserve as much as possible of Reverse for emergencies. When I was a broke hippie in my youth, I drove my `56 with NO Reverse for about 6 months....no Reverse and NO battery for another three...plus a bit longer with no throttle cable, either...but I didn't have to park in a garage.
The best one for you, for the minimum amount of parts-swapping to use it, would be a `61 through `66...but the odds of finding an early one that's still nice inside are getting pretty slim - I'd look specifically for a `65 or `66, and avoid anything older than a `64 unless the price is really right. It's a lot of work to put one in and test it; junkyards may offer a parts-only replacement guarantee (based upon the assumption that the trans must be good since the car was on the road up until the scene of the wreck...right?) but your labor is worth more than the used transaxle so try to find one that was actually road-tested before it was pulled. `67 and `68 transaxles are stronger still, and geared 6% taller for 15/1600cc engines, but they have different axles (and maybe brakes) so there's significant extra work involved in configuring one for a `65...they also use a smaller-O.D. starter bushing and the steel-sleeve approach to make one accept a 6V starter is a sketchy solution. Is your car still 6 volt? If it's 12 volt, what starter and flywheel are you using?
The transmission has internal detents for each gear position so as the linkage gets verrrry close to each gear, you can actually see the shaft that comes out of the transmission's nose pull itself into place as the spring-loaded detent ball inside finds home. Further motion of the shifter only makes the internals overshoot their ideal position slightly.
You mentioned previously adjusting the shifter to get more First gear engagement. If you did that without making the check I just described, you may have shortchanged the engagement of Reverse, 2nd, and 4th and shortened your Reverse life expectancy dramatically.
When you are driving in First or Second, romp on and off the throttle and watch the shift knob. Does it move by itself? That's a classic symptom of a loose or shot front transmission mount - if you overadjusted the shifter towards First to compensate, guess what? You are to blame for the present problem.
What's going on inside is that the Reverse sliding gear (the one that moves into place to engage straight-cut teeth on the perimeter of the 1/2 operating sleeve) gets worn, until it's all rounded off and looks smeared. The teeth on the 1/2 slider wear also, but usually not quite as much. As soon as any torque is applied (as you let out the clutch in Reverse) these rounded-over gears simply refuse to stay meshed and the Reverse sliding gear gets "spit out".
It doesn't take an entire transaxle overhaul to "patch" Reverse if the 1/2 slider isn't too bad, but just replacing that little Reverse sliding gear still requires some major surgery, beyond what the average shade-tree mechanic can do...takes some special tools, too, so it's best left to a pro. You can remove the transaxle, and if you feel adventurous the axles too, but I would not advise going much further.
Most folks just start shopping for a better used transmission at this point, and pick their parking spaces carefully to preserve as much as possible of Reverse for emergencies. When I was a broke hippie in my youth, I drove my `56 with NO Reverse for about 6 months....no Reverse and NO battery for another three...plus a bit longer with no throttle cable, either...but I didn't have to park in a garage.
The best one for you, for the minimum amount of parts-swapping to use it, would be a `61 through `66...but the odds of finding an early one that's still nice inside are getting pretty slim - I'd look specifically for a `65 or `66, and avoid anything older than a `64 unless the price is really right. It's a lot of work to put one in and test it; junkyards may offer a parts-only replacement guarantee (based upon the assumption that the trans must be good since the car was on the road up until the scene of the wreck...right?) but your labor is worth more than the used transaxle so try to find one that was actually road-tested before it was pulled. `67 and `68 transaxles are stronger still, and geared 6% taller for 15/1600cc engines, but they have different axles (and maybe brakes) so there's significant extra work involved in configuring one for a `65...they also use a smaller-O.D. starter bushing and the steel-sleeve approach to make one accept a 6V starter is a sketchy solution. Is your car still 6 volt? If it's 12 volt, what starter and flywheel are you using?
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65'VDuB
- Posts: 42
- Joined: Thu May 05, 2005 12:28 pm
Re: I think reverse hates me...
Thanks for your response. It's actually a '73 with a 12 volt 1776cc. The username was a past project. I guess I better start transaxle shopping!Marc wrote:Is your car still 6 volt? If it's 12 volt, what starter and flywheel are you using?
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Marc
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- Joined: Thu May 23, 2002 12:01 am
Re: I think reverse hates me...
They made the AT transmissions stronger overall, but took a big step backwards when it came to Reverse - the symptom you have is common on ATs (in my experience worse on the `74 and better on the `75-up - there were a couple of variations on the Reverse fork design). All of stuff I said about the shifter adjustment and front mount still applies.
You can graft in an AH (IRS trans from a `69-`72) but unless it's a late `72 (fat cross-shaft like your `73 has) you'll be putting in a weaker First so generally speaking that's not desirable. Look for a late AH - they have a zig-zag rib along the top of the case and have bolts rather than studs/nuts on the gear carrier, sideplate, etc.
You can graft in an AH (IRS trans from a `69-`72) but unless it's a late `72 (fat cross-shaft like your `73 has) you'll be putting in a weaker First so generally speaking that's not desirable. Look for a late AH - they have a zig-zag rib along the top of the case and have bolts rather than studs/nuts on the gear carrier, sideplate, etc.