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I'm having issues with my self rebuilt A413. Everything seems to be working great except it doesn't shift at WOT. I proceed to test line pressure at the line pressure port and the kickdown apply port, both read 0, and the pressure gauge tests fine with air. Any thoughts?
No 1-2 AND no 2-3 but will do both at lower throttle?
Honestly never had the opportunity to test 2-3 at wot, but shifts fine at part throttle.
Well, if it shifts normally under part throttle i assume it would probably eventually shift at WOT, it may just want to do it at too high of an rpm. Does it shift late (high rpm) during part throttle driving too? Wrong shift timing would generally probably have something to do with improper line+throttle pressure, or governor circuit problems (leakage, stuck governor valve, etc). The test port problem is curious. I tried looking at the hydraulic circuit diagrams in the ATSG rebuild manual to see if they showed where the test ports fell in the circuit, but it does not show that. But, just like any casting with drilled passages you can pretty much figure out where they come from and where they go by carefully looking at the part and thinking hard, but i don't have one to look at right here. I may get to see one of mine later today and will try to take a look. Generically speaking we know the blockage (if thats what it is) is somewhere between the pump and the test port which suggests valve body.
Someone might have blocked off the accumulator. That's what feeds the line pressure port. You have to put it in gear and use one of the other ports.
Ok, that someone would be me :)
Yes I blocked off the accumulator, as per the knowledge center, but I also tried at the kickdown apply port, in every gear. Same thing apply here?
Vigo, I've been winding it out to 7k and still no WOT shift. I've tried three different governor combo's and lowered the line pressure as much as the screw will allow. Part throttle shifts are perfect, but this is going to be drag only, really just concerned about WOT shifts.
Thanks!
The kickdown apply port should only show pressure in 2nd. Unless you have a manual valve body you won't see pressure there until the wheels are moving fast enough to make it shift into 2nd. Use the low band apply port(furthest to the right) and put it in manual low. If you have an aftermarket valve body without low band apply this won't work.
Did you do the bleed hole mod for more line pressure? You might have to make a custom governor weight if you did. Or go full manual. I'm assuming you already tried to mess with the kickdown cable/linkage.
Ok, that is really helpful, knowing which port to measure with the mods I have. I've never read that before, should almost add that to the A413 section of the knowledge center??
Yes, I did the bleed hole mod, and yes I did take some weight out of the large governor weight, probably just need to keep going with it. I've messed with the kickdown cable as well, again I was having trouble sourcing the correct way to do this?? I believe I pulled the clip at the transmission, applied full throttle and locked it back in, does this sound right?
Thanks!
That makes sense then. You will just have to mess with the governor weight until you get it close then you can use the line pressure adjuster and kickdown linkage to dial it in.
Someone correct me if I'm wrong but I think you actually need to make the weight heavier to lower the shift points. The throttle pressure is applied to the valve to hold it toward the center of rotation and the centrifugal force causes it to fling outward against the fluid pressure if I'm not mistaken. So a lighter weight will take more speed to move for a given line pressure and in turn throttle pressure. Increase the pressure and you need more weight to counteract the extra pressure. I just made mine manual and never messed with those so I'm not %100 sure on that.
If found the governor weight info confusing, lots of conflicting opinions. I am only concerned about WOT shifts, but many governor mods are for part throttle tuning so lots of the info is probably irrelevant.
Joe Dzwill from the link in the knowledge center:
"So making the big valve lighter or the spring for it heavier, will lower the WOT shift points."
http://www.turbo-mopar.com/forums/sh...light=governor