4 spd. pops out of gear.

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mopar head

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I bought a 833 from a member here decade+ ago, was told good. The build took me a decade to finish and put into service, he lied... Any how The gears grind in all forward speeds unless slow shifting and pops out of 2nd only on deceleration.

I been wanting to rebuild or replace this trans. I inquired @ Brewers if their rebuild kit would solve these issues before I wasted $ on a kit and tearing it down.
Their guy said I would probably need to send in the 2nd gear for machining.
I asked what is done, build up of gear and machined back to size? He said no I just file the synchronizer . I don`t consider machine work and file work the same.

Any of you guys rebuild a trans with issues like this and have solved with the basic rebuild kit?
Thanks.
 
You will not fix the 2nd gear issue with just a rebuild kit. That might not even just be a "gear" issue, that could be an issue with shaft play. It might also be the adjustment on the shift rods, but it's not unusual for 833's to pop out of second gear on hard deceleration with engine braking. A high compression engine exaggerates that issue too, it will engine brake harder which makes the 2nd gear popping out thing more pronounced.
 
Not directly related, but I have read somewhere that second gear is the weakest to be found in the Mopar four-speed. This supports my experience at the drag strip, having had stripped all the teeth off second gear during a power shift with ten-inch slicks. Second thoughts, maybe it was third gear? Heck, it was forty-five years ago, please forgive me.
 
Common issue.

Adjust the linkage per the directions in the FSM for a baseline.

If it still happens, move the adjustable swivel in or out one turn, try it again.

I have not had one yet that took more than two turns.
 
Common issue.

Adjust the linkage per the directions in the FSM for a baseline.

If it still happens, move the adjustable swivel in or out one turn, try it again.

I have not had one yet that took more than two turns.

There was no amount of adjustment that would keep my duster in 2nd gear on hard deceleration. It always popped out if I engine braked it going downhill at any significant speed, and I played around with the adjustment quite a bit. While the adjustment is a factor, the overall clearances on the shafts is ultimately the source.
 
Common issue.

Adjust the linkage per the directions in the FSM for a baseline.

If it still happens, move the adjustable swivel in or out one turn, try it again.

I have not had one yet that took more than two turns.
I`ve checked linkage alignment several times to put that out of the equation.
What are you trying to achieve here? pulling the gear more in mesh or to it`s limit/ stop point?
 
I`ve checked linkage alignment several times to put that out of the equation.
What are you trying to achieve here? pulling the gear more in mesh or to it`s limit/ stop point?

You're trying to keep the shift linkage from putting any additional pressure on the gear, increasing the chances of popping out when you load it in the opposite direction like when you decelerate. If the linkage isn't quite right it adds to the "pull". But that's not the primary force at work. If the problem is relatively minor the adjustment can fix it. If it's a major issue, it's more likely to be coming from a shaft or gear clearance issue, not just the shifter.
 
The linkage adjustment at the shifter is for when all the linkage & arms are pristine.

The holes in the lever arms wear, so do the pins inside them.

So altering the adjustment has worked for me so far with the 2nd gear popping out issue on a few cars over the years.
 
Here's a thread that explains some of the issues better than I can. Needless to say, it isn't always just a shift linkage problem. That can be part of it, but it's not the primary cause in most cases. There are several contributing causes, the shift linkage adjustment is only one.

Bumping out of 2nd
 
Not directly related, but I have read somewhere that second gear is the weakest to be found in the Mopar four-speed. This supports my experience at the drag strip, having had stripped all the teeth off second gear during a power shift with ten-inch slicks. Second thoughts, maybe it was third gear? Heck, it was forty-five years ago, please forgive me.


Third gear.
 
The linkage is the easiest to check, so it is a place to start the search for a solution.
 
Here's a thread that explains some of the issues better than I can. Needless to say, it isn't always just a shift linkage problem. That can be part of it, but it's not the primary cause in most cases. There are several contributing causes, the shift linkage adjustment is only one.

Bumping out of 2nd
Thanks, yea I searched threads found and read that one a few days back.
 
The best way to tighten up an A833 is to replace bearings, bushing, small parts kit, and the clustershaft. Next look at the synchro teeth on the outer synchro sleeves and the synchro teeth on the gears. Sometmes they are just too Goobered up and need to be replaced. Next, the brass sychro stop rings. Jamie has put out a great inexpensive book if you want to tear into it yourself. It is amazing to me how people can ruin a Mopar 4 speed...
 
I rebuild probably 20 of these a year, I just did a trans for a guy for his 72 duster. He had same issue with grinding, I finally ended up driving an hour down to take a look for myself. First thing I noticed was he had one of the shift tabs on wrong gear selector shaft, next was wrong linkage! He swore up and down it was adjusted right, which in neutral, was correct, but once you move the shifter both shifter tabs move and than you get grinding. We got his tabs on right and a new set of linkage from Van’s auto I believe, doesn’t matter they all use same supplier, but anyway that solved the grinding. Now on to the popping out of gear issue, 99% of time it’s worn keys on the synchro hubs, or a broken spring. The springs hold the keys up , which in turn holds it in gear. Popping out normally happens on deceleration, because it not under load. Feel free to message me if you have any questions. This is the transmission I am referring to after I rebuilt it for him and installed rods and tabs correctly.
Jeff

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You can file or machine the teeth back into shape often. But if they are too far gone it wont work
 
I bought a 833 from a member here decade+ ago, was told good. The build took me a decade to finish and put into service, he lied... Any how The gears grind in all forward speeds unless slow shifting and pops out of 2nd only on deceleration.

I been wanting to rebuild or replace this trans. I inquired @ Brewers if their rebuild kit would solve these issues before I wasted $ on a kit and tearing it down.
Their guy said I would probably need to send in the 2nd gear for machining.
I asked what is done, build up of gear and machined back to size? He said no I just file the synchronizer . I don`t consider machine work and file work the same.

Any of you guys rebuild a trans with issues like this and have solved with the basic rebuild kit?
Thanks.
The work I do on 2nd gear to fix the issue you are having is done in a Bridgeport with a carbide endmill.....not a file.
 
Thanks Jeff would you be able to tell me the proper #/letter of 1st and 2nd shifter tabs?
I`m not sure they`re correct.

All numbers/letters face out so you can read them, 1-2 should be LOW or L, 3-4 should be DIR or D, reverse should be REV or R. All point up on a regular 4 speed and only 3-4 points down on an O/D.
 
I had a 4sp that the c shifter ( one that shifter bolts to on side casing and moves syncro) was installed upside down and actually worked but had the same issue. Flipped it 180° and worked fine after that. May not fix yours but relates to the issue.
 
The work I do on 2nd gear to fix the issue you are having is done in a Bridgeport with a carbide endmill.....not a file.
I asked a lady to speak to a tech, I wrote down Don, if you don`t have a Don there, then I`m mistaken and spoke to you Dan. I just typed what I recalled of the conversation.
If you would, pm me the est. cost to make that gear right and turn around time.
Thanks.

I want this trans right or go another route.
 
I have been hand grinding points on those clutch teeth since the 80s; this is not rocket science. Usually there are 6 to 8 splines on each slider that do all the work, and they need to be back-cut so different undamaged splines come into play. Again, not rocket-science; just zip-zip with the die-grinder, and it's done. There will be 6 to 8 clutch teeth, per gear, that will/may need a similar back cut.
But grinding in all gears is NEVER a transmission problem. Let me rephrase that; In the hundreds and hundreds of many types of transmissions that I have "rebuilt", I cannot recall ever seeing one with 4 worn out brass rings. I mean chances are there was one or even a few, but I just don't recall it. In 40 years I can't recall ever seeing four bad brass rings. When they come to me the second gear is the bad one, the fourth is like new, and the other two are inbetween somewhere.
Grinding in all gears would be one of two things; either slippery oil or a dragging disc. The dragging disc can be one or more of several reasons, namely; Clutch Departure,or a bellhouse out of alignment, or a six-cylinder pedal-kit... which goes back to clutch departure.

Here's the test;
Start it up and let it idle. Depress the clutch pedal to the floor. Wait ~5 seconds , then attempt to put it into first. If it grinds,the input gear is still spinning, and you have either a departure problem, or an oil problem. Repeat but wait 10 seconds. If it still grinds you have a dragging clutch, probably because of insufficient Departure. But if no grind then drop the oil and install 75/90 EP Dyno oil with NO friction modifiers; that is to say NOT rear end oil. Then repeat the test.If problem solved yur done.
But if you have a departure problem with the pedal on the floor, then you got some homework to do.
First;verify that the freeplay is no more than 1 inch. I like 1/2 inch, because I have plenty of pedal left, NO departure problems, and I like the short stab on the pedal to make it happen. But 1" is the factory spec for lazy people, who don't like to crawl under there more than once a year.
Next you must verify that your Z-bar and TO fork are correct for your application. The Brewers site is very helpful.
Next you gotta verify that the Z-bar geometry is correct and stable. The bar must go from frame to bellhouse about parallel to the road and at 90* to the frame-rail in planview from above. And it must not move inboard/outboard on it's plastic bushings, and the frame end ball-stud must be securely welded to the fender/frame. The BH end must be securely anchored so it cannot move. On the stock BH this usually means 2 bolts.
Next; the TO fork must be the correct length, and sitting in the correct location in the window,which is; about centered vertically, and very near to the front edge. To change this, you use the fork pivot bracket, or the release bearing.
If you have a factory BH;
Finally, we get to measuring the departure. But first; with the trans in neutral, have a helper floor the clutch-pedal, then grab a tool and attempt to rotate the disc. It must move freely in both directions.
If it doesn't move at all with obvious departure, it's probably in backwards.
But assuming it moves;
keep turning it watching it wobble from side to side. If it drags on the PP or on the flywheel make a note of it. If it does it in several places make a note of that too. If it become hard to turn at any time, after all these checks have been made, then either the the disc is not properly floating on the splines, or, the departure is inadequate, or the disc is warped or damaged beyond usability, or the trans and crank are not on a common center.
The easiest to check is departure. I grab a couple of .080 feelers or anything about that thick, and with the helper still flooring the pedal jam them in there as far apart as you can and hanging down, then tell your helper to lift off the pedal. Let go of the feelers, then re floor it slowly. When the feelers drop out, yell to your helper to stop. Shimmy out and eyeball the distance from under the pedal to the floor (no floormat). This dimension should be more than 2 inches,and less than about three. Ok let your helper relax. But if this dimension is on or near the floor; OR, if the feelers don't drop out, then you have the wrong pedal ratio for your clutch. The whole pedal assembly will have to come out for inspection and possibly modification or replacement to the proper ratio.
Lessee where was I?.
Oh yeah, but if the departure works out right, then next is to make sure the disc is moving freely on the splines. IDK how you are gonna accomplish this; I always check this before I install the clutch. IDK. But I can tell you this; if you accidentally hung the trans on the disc with the retainer not yet in the BH, then chances are good that you bent the marcel carrier, and the wobbling during the spin test was pointing to that. And that brings us to;
If you have a scattershield, yur in trouble.
I suppose you could remove the driveshaft and insert a dummy-yoke into the tail, and you can turn the trans with that, but now you will have to put the trans into fourth, so the disc will spin, and you can sneak a peak thru the TO fork window. But I don't see how you can measure the departure. You'll have to figure something out.
And finally, when all else fails, did you dial-indicate your BH as to serviceability and make any required corrections? If the crank and the trans mainshaft are not on or nearly on the same centerline, you are gonna have issues. From hard- shifting to burned up mainshaft front pilot to unhappy bearings.
I think I got you covered.......

And here's a red-herring
There are two types of tail pieces, each with it's own Mainshaft bearing ........ and the big bearing, (a type of 308) is Mopar specific as to thickness. If you put a regular 308 in there, the mainshaft can walk backwards and forwards, which drags the gears with it, and so they may not be in the right place at the right time and the brass of course are out of their working range. And grinding in two gears is guaranteed. The only gear that is not affected is fourth/high.
As for the smaller 307 back bearing, I can't recall if it is Mopar specific.
And a double red-herring;
one of these bearings, maybe both, is retained in probably the most horrible way I have ever seen, and it is fairly difficult to properly install the retaining ring. If it was not properly seated, then the bearing is again free to walk back and forth, with guaranteed grinding in at least two gears. Again fourth is not affected, but the struts could pop out, making it impossible to return the trans to neutral.

Happy HotRodding
 
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ABodies with performance clutches need a firewall brace to eliminate firewall flex. I used hollow tubing flattened on each end and bent at each end to accommodate a master cylinder stud and then a bolt hole drilled into the driver's side shock tower/inner fenderwell. In the foto, it is painted black and is just barely visible running underneath the master cylinder and then underneath the two front header tubes on the driver's side.

65 Valiant  moter head on shot.jpg
 
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