904 Rebuild spring mix-up

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dartnlo

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I'm putting a 904 back together and the 3/8" ball spring (that goes inside the valve body) and the 1-2 shift valve spring look very close and I got them mixed up. How do you tell them apart?

At rest they are about the same height and diameter, the one on the right pictured below is stiffer and the material has a larger diameter. Both ends of the one on the right have a more even flat wear pattern on both ends as well.

20200201_170102.jpg

20200201_171050.jpg


Thanks,
Bob
 
Well looking back at my disassembly photos it looks like the stiffer slightly orange colored spring goes with the 3/8" check ball in the valve body. Which is the way I had them separated at first.

20200202_113535.jpg


20200202_113638.jpg


But now another issue, this picture shows my servos and accumulator as they came out. I think the spring that is on the accumulator belongs with the front servo. This along with the fact that it seems to be missing 2 of the 4 tang washers and some other washers, makes me think someone started to rebuild this and then gave up. So I think I'm just going to be saving this one for parts. It has way too much end play like over 1/16" of an inch.

I bought this transmission to use while I was rebuilding the dead one in my car but looks like I won't be.
 
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!/16"? That ain't nuffin.
Hmmm. I don't have a dial indicator so I'm going off how much the inner shaft moves in relation to the outer shaft. But it feels like a lot. I'm going to have to invest in gauges eventually. I guess I should measure it.
 
I have all the coils for a 68 to 72 904 measured and catalogued, and can probably walk you thru what spring goes where.
EDIT: almost all,lol

1/16 is only .062 and I think that is less than the .080 minimum spec. Besides, that is easy to adjust.
From what I remember, there are only three springs that can be installed wrong. so lets give 'er.
I'm here to help.
 
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I have all the coils for a 68 to 72 904 measured and catalogued, and can probably walk you thru what spring goes where.

1/16 is only .062 and I think that is less than the .080 minimum spec. Besides, that is easy to adjust.
From what I remember, there are only three springs that can be installed wrong. so lets give 'er.
I'm here to help.

I'm fairly certain I now have the 3/8" valve body check ball spring correct now. I think the the lighter weight spring is the 1-2 shift valve spring
springs1.png


I'm thinking now that the 2nd gear accumulator spring was removed in the last rebuild.
I think my front servo is supposed to have two springs, mine has the smaller center pin.

frontservo.png


It's possible I put the front servo outer spring with the accumulator by accident.

My servos:
springsss.jpg


What do you think?
 
frontservo-png.png

The big spring here,in the upper colorized servo, in inches,I have cataloged as
2.25x3.0 long and 4.75 coils of .150 diameter wire.
And my notes say that this coil is only used with second gear apply levers of 4.0 or greater.
 
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in this pic
springsss-jpg.jpg

>the L/R servo, in the center, should have a spring of;
1.93x2.65, and 5.875 coils of .185diameter.
>the accumulator spring you have shown , is usually left out in performance builds; the one you have shown, probably belongs in the front servo, on the far left. Measure and compare to the 2.25 x 3.0 previously listed.
>The factory accumulator is a short fat-wire affair, unmistakable because it is the only one like it. I do not have that one recorded. It appears to have about 7 very fat-wire coils, I'll guess about .180 thick. If you leave it out, you will have a Kapow! Neutral to manual-Low shift at zero mph. I don't like that, so I always put something/anything ,in there. The one you have shown won't stop it from slamming into gear..
 
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springs1-png.png

the factory relief valve spring I also do not have listed, but appears to have 9 coils, and the ball is a 3/8 . It blows off at about 275psi, so I'll guess it's pretty stiff. If you have a white one there, then you have a Kit in your trans, probably a TransGo TF-2
Jeepers, I also don't have the 1-2 spring listed Cuz to me it is obvious where it goes.
The only one similar to that 1-2, is the pressure regulator spring, and it I have listed as .62 x 2.37 and appears to have about 13 coils. If yours is blue, it came in the kit.
 
I'm fairly certain I now have the 3/8" valve body check ball spring correct now. I think the the lighter weight spring is the 1-2 shift valve spring That should be correct

It's possible I put the front servo outer spring with the accumulator by accident. That's what it looks like
 
in this pic
View attachment 1715465214
>the L/R servo, in the center, should have a spring of;
1.93x2.65, and 5.875 coils of .185diameter.
>the accumulator spring you have shown , is usually left out in performance builds; the one you have shown, probably belongs in the front servo, on the far left. Measure and compare to the 2.25 x 3.0 previously listed.
>The factory accumulator is a short fat-wire affair, unmistakable because it is the only one like it. I do not have that one recorded. It appears to have about 7 very fat-wire coils, I'll guess about .180 thick. If you leave it out, you will have a Kapow! Neutral to manual-Low shift at zero mph. I don't like that, so I always put something/anything ,in there. The one you have shown won't stop it from slamming into gear..

I think I'll order a new spring for the accumulator. Again, thanks for your detailed assistance.
 
I have seen several different accumulator springs, varying as to wire size, number of coils and overall length, and occasionally a color change. I don't know which one to recommend but I wonder how important it is,as long as, IMO, something is in there. IMO better too stiff than not.
My experience with autos is limited.
 
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