1-2 accumulator help
07-04-2007, 12:01 AM
#46
Yes replace the drum for sure, Replace the plate again. And look over everything carefully. When you get it back together if you dont feel second stop driving and figure it out , Vince is correct that there less strain in 4th to hold but to me it seems like you at least under very light throttle should feel some semblance of a second shift even if it is a slipping feeling. But anythings possible pehaps the 1-2 servo cant travel as far as the OD servo and the wear on the band is the issue from the broken acum.
Originally Posted by Arc00TA
The reverse input drum is badly rounded as well, I put a straight edge on it and it and it only touches near the very edges of the where the band was. I have a new one to put in.
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07-04-2007, 01:47 PM
#49
Sounds like you are on your way!
Earlier you questioned the looseness of the output assembly... it is not abnornal. In fact the engine builders next door at Xtreme H/P are in awe, are dumbfounded as to how the entire rotating assembly just does not sling itself apart. They really do trip out when they watch us build.... they are used to everything being very, very tight inside their engines... kinda funny to me.
While you have it out be sure to verify that all of the valves in the valve body are free, not binding. Make sure the clutches throughout the unit are in good shape and be sure to flush your cooler very very well.... that band is very roasted and it will have sent debris into the entire unit.
Now, do I remember right... this is the second time that ball has become lodged in the valve body plate in a short period of time? Is that a new plate in the photo? What shift kit is in it? These units do not like blocked accumulators, John has one on our bench now that is in pitiful condition out of an '02 SS car that run's 7.0x's (1/8) I believe. It is a 5 time loser, been to 2 different shops before looking us up... poor thing came in with valve body bolts stripped, both plate gaskets absent, multiple accumulator pistons in the bores and the list goes on... It is a terrible hack job, poor attempt at best. Point is, do not take short cuts in this transmission, it will not live. Make sure you understand which circuit that ball is in, probably 2nd right. But I could not tell from the picture.
Good Luck!
g
Earlier you questioned the looseness of the output assembly... it is not abnornal. In fact the engine builders next door at Xtreme H/P are in awe, are dumbfounded as to how the entire rotating assembly just does not sling itself apart. They really do trip out when they watch us build.... they are used to everything being very, very tight inside their engines... kinda funny to me.
While you have it out be sure to verify that all of the valves in the valve body are free, not binding. Make sure the clutches throughout the unit are in good shape and be sure to flush your cooler very very well.... that band is very roasted and it will have sent debris into the entire unit.
Now, do I remember right... this is the second time that ball has become lodged in the valve body plate in a short period of time? Is that a new plate in the photo? What shift kit is in it? These units do not like blocked accumulators, John has one on our bench now that is in pitiful condition out of an '02 SS car that run's 7.0x's (1/8) I believe. It is a 5 time loser, been to 2 different shops before looking us up... poor thing came in with valve body bolts stripped, both plate gaskets absent, multiple accumulator pistons in the bores and the list goes on... It is a terrible hack job, poor attempt at best. Point is, do not take short cuts in this transmission, it will not live. Make sure you understand which circuit that ball is in, probably 2nd right. But I could not tell from the picture.
Good Luck!
g
07-04-2007, 03:09 PM
#50
Well, I got a NEW new plate that is almost twice as thick as the old one. The old one is a stocker, but it did the same thing. I did pull all of the valves out of the valve body, everything in there looks good and moves without binding. I found and additional problem, I guess when I put the valve body back on before I put a long bolt in a short bolt hole, well now its a short bolt too because the sunshell chewed the end right off.
07-04-2007, 11:14 PM
#51
Well it sounds redundant, but let's identify that ball/hole. I'll take a look at a plate in the a.m. Meanwhile get a pic of the entire plate up if you can so we can be sure. This is not a new problem, seen it before, I just do not like making assumptions.
Good, the valve body is clean, that's important.
You got lucky, I did that way back when myself! Only mine locked the shell as it went by, bending the bolt, but not breaking it, I had no fun making that repair.... that was a memorable day for me. I will always remember that dissapointment. That night I drank a beer and made a sacrifice to the car gods while cussing the design boys again!!!!
But I digress..... get back to us tomorrow....
g
Good, the valve body is clean, that's important.
You got lucky, I did that way back when myself! Only mine locked the shell as it went by, bending the bolt, but not breaking it, I had no fun making that repair.... that was a memorable day for me. I will always remember that dissapointment. That night I drank a beer and made a sacrifice to the car gods while cussing the design boys again!!!!
But I digress..... get back to us tomorrow....
g
07-04-2007, 11:44 PM
#52
Alright, heres the whole plate. Red circle is the ball that went thru, blue circle is some plug that was put in there? I really dont know, I just know when I got it that it was in there. The new plate does not have a plug, and the hole the checkball went thru on the new plate is less than 1/2 the size of the ball.
07-05-2007, 09:17 AM
#54
Thanks for the clarity.... Indeed the red hole is the 1/2 upshift or band feed hole. The blue hole is the 3/2 downshift hole. It helps apply the band during the downshift.
Knowing that the ball was stuck in the 1/2 feed hole would explain why the band fried, there may have been damage to the band when it happened the first time. And the second time it occurred probably finished it off. When that 1/2 feed hole is blocked by the ball the band is left to apply via the much smaller feed hole located directly next to the larger hole where the ball was lodged, this would create a very slow apply of the band, basically it slipped until that circuit filled. Also, it severely slowed down the band release when the pressure was released during a 2/1 downshift and a 2/3 upshift. In other words the band was applied when it should not have been and was very slow to apply when it should have been holding the reverse/input drum!
Now, the fact that this happened twice is probably a direct result of high line pressure. I would recommend getting a new EPC solenoid. As the name implies it is the solenoid that controls line pressure. Also have a tuner check the settings in the pressure tables of your PCM. Also, check the pressure regulator valve in the pump to make sure it has not been modified by adding washers to increase the spring rate.
Did this transmission have a harsh 1/2 upshift and a harsh 3/2 downshift regardless of throttle position? ...I would bet that it did.
Hope that helps.
Good Luck with it.
g
Knowing that the ball was stuck in the 1/2 feed hole would explain why the band fried, there may have been damage to the band when it happened the first time. And the second time it occurred probably finished it off. When that 1/2 feed hole is blocked by the ball the band is left to apply via the much smaller feed hole located directly next to the larger hole where the ball was lodged, this would create a very slow apply of the band, basically it slipped until that circuit filled. Also, it severely slowed down the band release when the pressure was released during a 2/1 downshift and a 2/3 upshift. In other words the band was applied when it should not have been and was very slow to apply when it should have been holding the reverse/input drum!
Now, the fact that this happened twice is probably a direct result of high line pressure. I would recommend getting a new EPC solenoid. As the name implies it is the solenoid that controls line pressure. Also have a tuner check the settings in the pressure tables of your PCM. Also, check the pressure regulator valve in the pump to make sure it has not been modified by adding washers to increase the spring rate.
Did this transmission have a harsh 1/2 upshift and a harsh 3/2 downshift regardless of throttle position? ...I would bet that it did.
Hope that helps.
Good Luck with it.
g
07-05-2007, 06:13 PM
#56
I grabbed a new EPC solenoid, one other thing. I got a whole new 1-2 accumulator, housing etc. It has 2 springs in it, one big one little. When I pushed the new metal piston into it it only comes back out to the end of the big spring travel. This is normal right? Im assuming when it gets pressure behind it it will come all the way out. I ask because it was really tough to get he piston in and I dont want it only having half of its travel or something.
07-05-2007, 08:35 PM
#57
There are several different setups on the market for the 1/2 accumulator. What you have is going to be fine.
...........
On a side note, It was pointed out to me by a good friend that I was not only wrong but pitifully mistaken, I should have thought about it, I did not and for that I offer this public recanting of the following statement (dangit, I hate it when I'm wrong.. lol)..... I stated that the fluid pressure is released during a 2/3 upshift. When indeed it is not released during a 2/3 upshift, fluid pressure is introduced to the front and back of the 2nd servo piston. Because the "back" side (3rd) has more surface area it will overpower the front side (2nd) and will not only release the band but will serve as an accumulator for the 3rd gear shift.
Snap.... I knew that... crap.
Sorry for the confusion... I think I caused a few guys to get out their manuals on that one... Nope I do not have any new info here guys, I was wrong on that one.
I'll take a "Early in the morning, 1st cup o joe" pass please if ya's don't mind so much.
g
...........
On a side note, It was pointed out to me by a good friend that I was not only wrong but pitifully mistaken, I should have thought about it, I did not and for that I offer this public recanting of the following statement (dangit, I hate it when I'm wrong.. lol).....
Also, it severely slowed down the band release when the pressure was released during a 2/1 downshift and a 2/3 upshift.
Snap.... I knew that... crap.
Sorry for the confusion... I think I caused a few guys to get out their manuals on that one... Nope I do not have any new info here guys, I was wrong on that one.
I'll take a "Early in the morning, 1st cup o joe" pass please if ya's don't mind so much.g
Last edited by Gilbert@Ace Racing; 07-05-2007 at 08:46 PM.
07-05-2007, 08:43 PM
#58
Thats fine, its all greek to me. I pretty much have to take your word on it as I know just enough about auto transmissions to get by, I have no problem taking it apart and all that just have to have a manual to look at. I put the piston in the same way the stock one came out when I first took it out, so the flattest side of the piston with the little nubbies around the edge is against the separator plate. Should I change it around somehow?