Trans help for a friend needed

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memike

memike

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He is having a problem, at 700-800 rpm if you shift from Park to reverse, its very hard
He is about to pull the valve body and see what is going on, he don't race this nice Dart but changing just the accumulator spring help this ? everything works good.. It has a shift kit of some kind and I have found that the accumulator spring could do this I think. Thank you very much
 
Mike, there could be too much play in one or both of the U joints, the rearend may have the "traditional" clunk as do a lot of the cars that have not been gone through.

I would check the easy stuff first, then move on.

What car? What rearend?
 
Bad Sport said:
Mike, there could be too much play in one or both of the U joints, the rearend may have the "traditional" clunk as do a lot of the cars that have not been gone through.

I would check the easy stuff first, then move on.

What car? What rearend?
Click to expand...

Thank you Bad Sport, It is a member here Popdart ,383, 727, 8 3/4 rear 3.91, 73 Dart Swinger, "work in progress" I will send him this thread and see what we all can come up with and save him time and doing things 3 times or throwing monies at it :color:
 
............the line pressure could be set too high, u could check it with a gauge or pull the pan to see how many threads r showing......u could also back off the kd alittle.............kim........
 
when going from park to rev and it bangs hard try this hint. first pull the lever all the way to LOW then to rev. mostly this is 1. idle set to high. 2. converter stall to low for the cam. 3. the rev / low band is set to loose. or damaged. number 3. is the most common thing. if need be call these cats http://www.areds.com/.................have known them since the late 60s. they can answer ANY Q.
 
some shift kits install a rod in the the accumulator inside the spring so there is no damping.
 
pishta said:
some shift kits install a rod in the the accumulator inside the spring so there is no damping.
Click to expand...
This could be part of the kit that was put in, How could he reverse this pishta ? or will he need a new valve body if it was drilled out sir, or if it even was drilled for a kit.
 
oldkimmer said:
............the line pressure could be set too high, u could check it with a gauge or pull the pan to see how many threads r showing......u could also back off the kd alittle.............kim........
Click to expand...

Thank you Kim, I hope this helps him :cheers:
 
moe7404 said:
when going from park to rev and it bangs hard try this hint. first pull the lever all the way to LOW then to rev. mostly this is 1. idle set to high. 2. converter stall to low for the cam. 3. the rev / low band is set to loose. or damaged. number 3. is the most common thing. if need be call these cats http://www.areds.com/.................have known them since the late 60s. they can answer ANY Q.
Click to expand...
Thank you moe :glasses7:
 
Hi guys . . . . I'm the guy who needs direction. My 73 Dart Swinger has been a "work in progress". It's a 383, 727, 8 3/4 rear 3.91. I'm an ole guy, 66, just tryin' to get the Dart to be a reliable cruiser. She has a HURST VMatic shifter (which I hate, and it may be going this summer), supposedly has a shift kit installed, with LOKAR cable. One of the problems I'm having is that if I manage shifting the HURST from PARK down to DRIVE it's like slamming into the gear at 2500 rpm. Same into reverse. I had some problems with the engine idling too high but pretty much solved that with a new HOLLEY carb. and timing adjustments. The 1-2 and 2-3 shifts don't seem "hard", but then again I haven't really had opportunity to pour the coals to her to see how the shift would be. So I'm really addressing the idle in PARK to DRIVE or REVERSE shift, not 1-2 or 2-3 shifts.
I'm about ready to give up working all summer on the car with little or no cruising time. Don't get me wrong, I enjoy working on it, but I should enjoy driving it too. Thanks ahead for any comments . . . .
 
There are certainly a few things I would check before goin to all the trouble to snatch the valve body. The kick down being out of adjustment or not returning properly could certainly cause that. I would sure as heck check it.
 
I guess I'll start with the easy stuff as Bad Sport mentioned. I'll check the universals again. The car doesn't want to idle below 750-800, likes to stall. I would like to get it down to 600-650 if possible. But I believe that if I get the idle down, it will still have a pretty harsh engagement. I'll address that again when I can open the doors of the barn. To RustyRatRod, if it's not sticking, can the kickdown affect the trans engagement at an idle? It's presently adjusted so there is no contact (end of cable / carb throttle)? Can choke / fast idle (cold - warm) have an effect on this? I will check to see if it is sticking or influenced by fast idle. Tell me what you all think. Thanks
 
Pishta is right about the shift kit possibly swapping the accumulator spring for a blocker rod. That part of the mod makes it shift firmer into 2nd gear but it can also make it rough going into drive because there's no dampening there. I don't do that mod on a car unless it has a high stall converter to dampen the shift into drive.
 
-In Park the line pressure is dumped at the manual valve, and falls into the basement at some 5 to 30 psi.
-In reverse, the line pressure jumps to the max the pump is capable of; some 255psi. But worse, all this pressure goes straight to the L/R servo and hi drum(front clutch). And even worse; the accumulator is bypassed.
-So in the P to R shift the line pressure goes from absolute minimum pressure to absolute maximum pressure. Clunk (harsh engagement) is un-avoidable. A higher stall can absorb some of it.
-If the line pressure is set higher than normal it will aggravate this, and pulling the KD linkage ahead doesnt usually affect this as the internal adjustment nullifies this.I see no easy solution to this dilemma.
-Even in neutral the line pressure may be lowered to 60psi, but the N to R is still going to be harsh.
-If you yank the lever from Park(55psi) to Low(also 55psi), this will bring the accumulator on line with the L/R band, for a softer engagement. Then if you shift from Low to Reverse, the accumulator drops out, while the front clutch engages. this might soften the shift. But just try that shift.
-I think Chrysler put that wavy piston retainer in the front clutch for a very good reason. This is one of them.
-The line pressure adjuster works over a very small range. That wavy spring in the hi-drum and a bit of extra clearance there can work wonders, at a slight expense of the 2-3 shift. I always leave it in, in mine.
-I suppose a softer spring and a looser adjustment in the L/R servo would accomplish a similar result without the 2-3 compromise. Or the introduction of a leak in that pressure circuit, since its not used for anything else.
-Years ago I ran a 904 with a Trans-Go kit, behind a 318, in my S-clone. I spent many hours on that unit. In the end it was a dream. And no you cant have it, lol.
 
fishy68 said:
Pishta is right about the shift kit possibly swapping the accumulator spring for a blocker rod. That part of the mod makes it shift firmer into 2nd gear but it can also make it rough going into reverse because there's no dampening there. I don't do that mod on a car unless it has a high stall converter to dampen the shift into reverse.
Click to expand...
Just so I am reading this right, you are saying that the someone who installed a "shift kit" in my trans may have removed the accumulator spring and installed a blocker rod, correct? Just checking, in case I get in that far.
 
Popdart said:
Just so I am reading this right, you are saying that the someone who installed a "shift kit" in my trans may have removed the accumulator spring and installed a blocker rod, correct? Just checking, in case I get in that far.
Click to expand...


Exactly.

(just in case Tracy fishy68 got busy or something and couldn't answer.)
It mat even have the spring, but it could be broken jamming the accumulator.

I either case start there if there isn't any play in the u joints.

You have answered the other simple possibilities.
 
AJ/FormS said:
-In Park the line pressure is dumped at the manual valve, and falls into the basement at some 5 to 30 psi.
-In reverse, the line pressure jumps to the max the pump is capable of; some 255psi. But worse, all this pressure goes straight to the L/R servo and hi drum(front clutch). And even worse; the accumulator is bypassed.
-So in the P to R shift the line pressure goes from absolute minimum pressure to absolute maximum pressure. Clunk is un-avoidable. A higher stall can absorb some of it.
-If the line pressure is set higher than normal it will aggravate this, and pulling the KD linkage ahead doesnt usually affect this as the internal adjustment nullifies this.I see no easy solution to this dilemma.
Click to expand...
I understand your point . . . but this is not so much about a "clunk" as it is about a "harsh engagement". There is no smooth transition. There is no transition. I'm 66 and have driven a few older cars when they weren't old yet. But this is way more aggressive than normal for a drive train of this vintage. I'm not looking for perfect, but at least a "dampened" transition. I get very nervous every time I shift it out of Park. . .
 
TrailBeast said:
Exactly.

(just in case Tracy fishy68 got busy or something and couldn't answer.)
It mat even have the spring, but it could be broken jamming the accumulator.

I either case start there if there isn't any play in the u joints.

You have answered the other simple possibilities.
Click to expand...
LOL . . I just love the part where you said "simple" possibilities . . . . :)
 
Popdart said:
LOL . . I just love the part where you said "simple" possibilities . . . . :)
Click to expand...

Right? :D

I think someone mentioned it already, but band adjustment can help that also.
If you tighten the rev band adjustment till you cannot turn the driveline by hand, and then back it off just to where you can turn it then lock it down.
This removes any possible momentum the band might gain before it clamps down on the drum.

Of course this adjustment is inside, so remember this when checking the accumulator for the spring.
 
TrailBeast said:
Right? :D

I think someone mentioned it already, but band adjustment can help that also.
If you tighten the rev band adjustment till you cannot turn the driveline by hand, and then back it off just to where you can turn it then lock it down.
This removes any possible momentum the band might gain before it clamps down on the drum.

Of course this adjustment is inside, so remember this when checking the accumulator for the spring.
Click to expand...
Ok, I will. Thanks
 
Pop
Sorry, clunk was wrong.(I will edit) But you may have missed the whole story by focusing on the one word. The point was, there is absolutely no pressure dampening in reverse.The accumulator is bypassed. So a harsh engagement is un-avoidable.
-Its the accumulators job to soften or dampen all the forward shifts, so most kits defeat it or modify it to speed up the shifts.
-You will need to obtain instructions for the kit that was installed to see if this was addressed, and verify that the step was performed. Or open up the vb. But that might not help you if you dont know what the various oem springs look like.
-Im 62 this June, so I kinda understand what youre going through. Perhaps a return to a stock valve-body is in your future.Its a very simple bolt-on. The kitted vb may not be able to be returned to stock, and is best left shelved.
-The oem vb that you obtain,can be modified with a shift improver kit, that is a lot less harsh, if you so desire.
 
AJ/FormS said:
Pop
Sorry, clunk was wrong.(I will edit) But you may have missed the whole story by focusing on the one word. The point was, there is absolutely no pressure dampening in reverse.The accumulator is bypassed. So a harsh engagement is un-avoidable.
-Its the accumulators job to soften or dampen all the forward shifts, so most kits defeat it or modify it to speed up the shifts.
-You will need to obtain instructions for the kit that was installed to see if this was addressed, and verify that the step was performed. Or open up the vb. But that might not help you if you dont know what the various oem springs look like.
-Im 62 this June, so I kinda understand what youre going through. Perhaps a return to a stock valve-body is in your future.Its a very simple bolt-on. The kitted vb may not be able to be returned to stock, and is best left shelved.
-The oem vb that you obtain,can be modified with a shift improver kit, that is a lot less harsh, if you so desire.
Click to expand...
I pretty much understood what you said, I was just clarifying that it wasn't a monstrous metallic "clunk" but an aggressive transition. I most definitely would like to "de"-shift kit the valve body/trans and return to stock. Next will be the damn shifter. lol. Thanks for your help. :)
 
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