hi folks, new guy. 904 torqueflite on a 318, 75 valiant. i just did the low-reverse band adjustment as per a 70s chilton manual (4 turns out), and the carb to tranny linkage adjustment via advice posted online (gas pedal depressed to the floor, carb linkage adjusted all the way back toward firewall, and tranny linkage all the way back toward rear of car). things improved, as before this i was slipping real bad going into 3rd, now it drives soild. my issue is now i only detect one shift and cant be sure what gears i have, if in fact one is missing. it starts from a stop just fine, so i dont think 1st gear is gone. i can open it up on the highway and it sails, but as soon as i take my foot off the gas, speed decreases rapidly as if something were pulling it back. before this adjustment, 2nd gear peaked at about 45mph, so its hard to believe its still in 2nd, not reaching 3rd, if i can go 70mph - but if i move the gear select to 2, i can open it up as if in D. i havent tried to go highway speeds with the shifter on 2, but my feeling is it will. maybe the linkage adjustment tightened things so much im just not used to it, and the missing shift is seemless? looking at a long distance trip so i want to get this right. any ideas?
904 band adjustment stopped the slip, but added a mystery
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With light throttle pressure on level ground, the car should shift into 2nd around 10-15 mph, and into 3rd around 25-30 mph. The more throttle you give it, the higher the speed it shifts at. My 66 Plymouth would shift at full throttle into 2nd at 42 mph and into 3rd at 68 mph. If you don't get the same reactions, it's possible that the downshift linkage is misadjusted.
A tachometer would tell you what gear you are in. Depending on axle ratio, you can expect around 3000 RPM at 70 mph in 3rd.
A tachometer would tell you what gear you are in. Depending on axle ratio, you can expect around 3000 RPM at 70 mph in 3rd.
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One thing for sure, the linkage adjustment is one of the most painful and time consuming things for the 727/904 transmissions. At this point, since the book never seems to get it right, follow the directions and it still doesn't work quite right, it's figure out where the shift points are and then adjust them to where they need to be to drive comfortably. Bob is right on the shift points, now getting there is the fun part. It usually takes several trial and error attempts to get it where you are comfortable, so make sure the springs are good, no binding, and then small incremental changes in the kickdown pivot on the carb linkage point. Now. Some of the adjustment rods are threaded, some are bolt and clamp, not sure which you have, but adjustments of .020-.030 at a time to dial it in, test drive, adjust again until you get it where you are happy. Have fun, and good luck.
To adjust the throttle lever linkage, first raise the car high enough to get to the tranny linkage [be safe]. There is a sliding block on the tranny throttle lever. Loosen the clamp bolt. This block must move freely on the linkage rod. Then open the carb choke fully and wire it open. Drop the fast idle cam down. Go back under the car and push the tranny throttle lever fully forward. Hold it there and tighten the clamp bolt.There should be a medium duty spring ahead of the clamp which keeps forward tension on the linkage assy. Road test.
Update: thanks for the help btw. I did just as pt006 said, clutch wired open, cam down, tranny lever forward, then reclamp the linkage. That gave me some progress.. at one point it shifted into 3rd at 75mph, every other time no dice. BUT, if I take my foot off the gas at high speed, at which point it slips out of gear, I can hit the gas and it catches in 3rd most of the time. So the slip is back in all gears when I lift my foot, but when I repress the pedal it catches seemingly in the right gear. I figure I will repeat the same adjustment. If that doesnt take then maybe ill try different fluid with stop slip to see what results I get
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My brother's 74 Valiant did this. Try adjusting both bands. If that doesn't work, the clutch material maybe worn down too far.
If the car is worth saving, I'd throw a used 904 back into it. 273, 318, 360 should fit. Non-lockup? They go in and out pretty quick. But pull the pan on the 'new' one and inspect before installing. And use the 'new' torque converter, as yours might be contaminated.
Right but its another chance buying a used one if I can find it and I was in the process of selling it when this all happened. Too broke to pour any more money in, already did the brakes, carb, tires and a bunch of other things. Now im just looking for someone to take it for a grand so I can move forward, but buyers are scarce in a small town, we'll see how it goes. Yeah its very much worth saving, very nice car
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Post pics, please.
I dont know why but it wont take anymore pics. I get an error msg. Clean interior of gold and brown, no cracks in dash. Tight headliner, no sag. Nice gold carpet. Carpeted trunk. V8 318 very strong. Hard top is coated with a sand textured coating, not vinyl. Rear leaf springs are orig and sag so I lowered the front via the equipped bolts to match. New belts hoses wires and all tune up, etc. Rebuilt carb, new tires. All that is new within 500 miles driving, as is entire front braking system from lines to calipers to discs
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Very nice car.
Would be much better to replace the rear springs. When you lower the car by adjusting the torsion bars, you change not only the spring rate of the front end, but also the handling characteristics and, I think, the alignment.
Would be much better to replace the rear springs. When you lower the car by adjusting the torsion bars, you change not only the spring rate of the front end, but also the handling characteristics and, I think, the alignment.
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My brother sold his Valiant without fixing whatever caused the unexpected downshift to 2nd, but I would try the band adjustment and fluid and filter change before giving up on it.
Also, maybe adjust the downshift rod further. At what speed does it shift from 1-2 on level ground with light throttle?
Also, maybe adjust the downshift rod further. At what speed does it shift from 1-2 on level ground with light throttle?
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