AT1545 thread

[cadillackid]

so i must ask if the 2 bolts which dont line up are nextr to each other... and if so is it possible the converter sagged because of the pilot size mismatch? where if you loosened out the other 4 by a couple turns. would the converter be moveable such that it would then center up on all 6.. and you could tighten all down then in an every-other-one pattern through 5 rotations of the engine.. which is how I tighted mine down.. I inserted them all.. then went back and tightened every other one.. which took 2 revolutions... then I checked them all again every other one... 2 revolutions.. (total of 5 revs)

-Christopher

[turf]

the holes are not next to each other. i believe its 3 then a hole, 1 and a hole.

there is not much room to have a loosened bolt make the round on the flywheel. they have to be almost flush to clear the flywheel housing. i will try to center it like you say.... 2 revolutions around, hold my tongue just right and keep fingers crossed.

X2 on finding parts for a 1545. i think it'd be tough. "Discontinued" was the word i kept hearing from my part guys. Chris understands the differences better than I, but i think an MT643 would be an easier swap. at least they had been mated by a factory engineer and not a backyard mechanic.

i needed a breather for the 1545. unable to find one (discontinued), i found a transmission vent from a mitsubishi eclipse that i was able to retap the thread and fit it into the 1545 body.

[cadillackid]

the biggest issue with swapping in a 643 is the weight... a 643 is a HEAVY beast... I think I read where the 643 Must have a full cross member or auxilliary mlounted device of some sort.. which means making one or finding a bus like the one being swapped into and snagging the cross member...

-Christopher

[turf]

good news! bad news!

the good news is:
its back together and the bus moved on its own power.

the bad news:
i've misplaced a retaining clip that secures the modulator. so except for that, its finished. i hope.

its a tight fit, the flex plate is on the verge of being bound up. if anything, that hub could be shorter - imo. idk.

we tightened the case bolts first and then the flex plate..... that was bound up and unable to spin by turning the alternator.
we loosened both back. did the flex plate first and then the case and the flex plate would still spin.

i put a hole in one of the hoses and need to replace it. and i need to find that retaining clip.

[cadillackid]

Fantastic that it's coming together!!!

Is it the electric modulator? If so I might have one of those clips that fits a 545 if it's the same kind. I can look if you want
Christopher

[turf]

thank you Chris, i may take you up on it.

I'm going to search good tomorrow and if i don't find it, i'll order it or try and get a hold of you.

it looks kinda of like this:

[cadillackid]

I know exactly this piece.. and I think I saved mine.. i sent my old 545 down the poike the other day. but i saved the modulator and a few brackets and such.. I believe this part i saved too..

make sure your electric modulator is good! or is yours a mechanical cable type?
-Christopher

[turf]

i found it.

it got swept up in a box of floor dry. i think i used 20 pounds of floor dry for the swap. glad the floor dry was piled up and not tossed into the trash yet.

lucky day. now just to replace the broken hose and she should be good.

[turf]

i got the modulator clip installed and now i'm waiting on a fitting for the transmission hose.

i re-routed the trans lines (probably how i damaged the one) but that line goes from the trans to the big cooler first. when i first installed the cooler, i had trouble since it was a metric cooler and i had JIC flare fittings.
anyway, i had to order a metric M20 to JIC 10 adapter. that got me fixed up once.
here is the outlet of the big cooler with the metric adapter from my install a year ago.


i will copy that for the input side. now the input side has a metric banjo fitting and i'm waiting on the adapter. so i will delete this piece and replace it with a short 90* hose. my temp sensor was in there too. i broke it by pulling out one of the wires. it think when i get it replaced, i'll put it in the pan in an unused bung.


here you can see where the old tube fit in and i'll need a short jic 90* female and a male.

[turf]

IT MOVED!!!

i took it out on the road today. got up to 65. and came back home.





seems to work, i still got some adjusting to do. but it worked.

i had been waiting on a metric to JIC fitting that came in at napa today. you can't see it, but the shiny elbow on the right is attached to it and now the hydraulic lines are complete again.



no leaks
i filled it with fluid and tried it out.

no hiway time yet, maybe tomorrow. it shifted at least to 4th.

the speedometer doesnt work anymore. at my fastest, it only said 20mph, the gps had me at 68.

i played with my AFC again while it was sitting there and ground down the foot. i need to readjust the star wheel and smoke screw now, it seemed lugged down as i was driving.

i ordered a new trans temp sensor and it is not here yet. i took the plug from the old transmission and tapped it to fit the sensor. when the new sensor comes, i will get the pan temp.

[cadillackid]

super cool!!!! wierd it had a metric fitting for the Cooler lines.. . darn MIL spec stuff lol..

did it feel like the lockup worked when you got it into 3rd and 4th?
-Christopher

[turf]

there were plenty of new noises so i was a bit distracted. my adjustment to the AFC was overkill and i have to dial it back.
i just drove it about about 10miles of some pretty easy country roads.
i counted 4 shifts twice. i was hoping to hear a 5th but havent.

the book says
1u-2u, 2u-3u, 3u-3L, 3L-4L

pretty sure i made it to 4th. it feels pretty much the same as the old one. so far.

Working

there is a new real high pitched whine, that maybe the new flywheel connection.

oh my oil cooler was used off a Mitsubishi truck. so the metric is my fault.

[cadillackid]

yeah you should feel the converter Lock about halfway through 3rd gear... it feels almost like a shift.. then once in 4th.. watch your tach and speedometer... they should move together... meaning unlike the 545 where when you let off the gas the tach would drop wildly and then jump up wildly when you gave it gas you should see the tach slowly move up or down as vehicle speed incfreases or decreases.. this lets you know Lockup is engaged.

the flywheel connection should cause a whine, im not sure which gearset the 1545 has but if if you are getting a whine as it shifts from 1-2 and 2-3. that would mean it has the hellical cut gears. and is what the older 545's sounded like.

if its a whine with engine revs then double check your fluid is full. after running through all the gears at the shifter engine running.. would tend to think its a front pump whine at that point.
-Christopher

[lucasd]

This is an awesome mod thread! I really like how you have documented all the stages of your problem solving process... though I suspect you might have wished for more "solving" and less "problem" along the way... ;)

Anyway, it looks like it is working out. Did you keep any sort of tally for what the overall parts and machine shop time ended up costing you?

[cadillackid]

this is a great mod thread, I like these kinds of threads.. then again im into modding and uodating the mechanicals and electromnics of busses more than conversion so this thread is kickass!!
-Christopher

[turf]

some more problem solving

i was playing with the AFC, so.... maybe its related and i'm still tinkering with that. but..... and its a big but!

when the trans shifts into second gear, it drops the rpms down and luggs the engine, sends smoke out the back. with some time it recovers until it shifts into third, then the same lugging.

by lugging - i mean it seems to extinguish the fire the turbo was cooking.

the shifts points are about 2200rpm and then it drops down to 900-1000.

any suggestions?

[cadillackid]

sounds like the modulator isnrt adjusted correct... did you have a cable modulator or an electric one on your AT545? the modulator is what should put your transmission into high shift opojt mode.. although 2200 may have been neare the top on the military engine that trans was designed for.. what is the factory redline on your 5.9? did you used to shift somewhere in that 2500-2700 range?
-Christopher

[turf]

i did a few more changes last night and its a bit better but not right. i set my AFC back to as close to original as i could get it.

the shift points are wonky

1-2 happens at 1500ish rpms and only knocks you back 1-200 rpms. the shift is barely noticeable.

2-3 this is the first one that lugs. shift is about 2100 - and drops down to 900 rpm, lugging.

3-4 also lugs but not as bad. it shift around 2100- and drops - 1200 lugging.

[cadillackid]

1-2 is barely noticeable because it is early and the converter is unlocked aso you are running against the stall speed..

2-3 and 3-4 lug because they are early and locked converter..

have you adjusted the shift modulation cable or does it have electronic?

there are 3 shift point adjusters on the valve body inside the pan i believe.. or perhaps you need a different governor.. not sure what happens if you take the governor from the 545 and pout it on the 1545.. the governor is the "hump" on the side of the trans near the tailshaft..
-Christopher

[Booyah45828]

Swap the governor from your 545 to 1545. I would think that the governors would be similar between the two considering the 3116 and 6bt are similar engines.

If you have the modulator cable adjusted correctly (tight at WOT), shifting then comes down to the governor. After you have all of that adjusted correctly, you can then adjust the individual shift points in the valve body, but most of the time those are spot on from the factory.