First questions on my 727 rebuild journey
- Thread starter AR67GTX
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I was looking at your pump rotor the teeth didn't look symmetrical looked like one side was worn or is that the picture?
miller
Well-Known Member
You had said the trans was shifting good...good sign. Might not be anything there, just needing apart, clean, and look. (I always leave it 'till last, plenty of other parts to play with...just me.)
Ha! I only know enough to keep me in trouble.
Don't necessarily agree with that last sentence miller , being modest ?
miller
Well-Known Member
Being honest. There's plenty I don't know. Some of you guys put me to shame.
I'll take a closer look. That's my greatest concern - recognizing bad parts. I've had two 4 speeds rebuilt for me over the years by guys that do it for a living and I always get them back with a box of parts that were replaced. I take them out and pick over them and I can't see anything that would tell me they aren't serviceable - but the transmission works. That's what experience does for you - but it's kind of like voodoo to the inexperienced (me).
miller
Well-Known Member
Yeah, same here. Wear pattern on the pinion gears don't look right. 'That' could easily be your whine.
Just another comment on the shift body...doesn't matter how good it looks, or acts...I've always taken them completely apart, clean all the parts, inspect, and back together. That way 'you' know what's there.
We had only our second clear, mild day of the new year yesterday so we were trying to cram in as many outside activities as we could. Back to rain today so I'm going to go out today and go through each component individually and try to evaluate what's good and what's not and start getting stuff ordered.
I may just go with a new B&M converter. For what they cost for a 11 inch model compared to shipping my old one to and from Ft Smith, rebuild cost, and then no way of knowing exactly what they did to it, I think I'll have more peace of mind. Maybe I can even find the part number on Amazon and get free shipping.
I may just go with a new B&M converter. For what they cost for a 11 inch model compared to shipping my old one to and from Ft Smith, rebuild cost, and then no way of knowing exactly what they did to it, I think I'll have more peace of mind. Maybe I can even find the part number on Amazon and get free shipping.
Never seen pinion gears whine, your teeth look normal. If there is an issue it will be with the needle bearings. Clean each thoroughly with solvent and recheck. Replace the pump bushing, the rest will be fine. DO NOT remove the outer race of the over running clutch from the case unless it is loose or you plan on replacing it with a high quality Super Sprag, (not the standard bolt in junk) which in your application is not needed. Make sure the outer surface of the inner race is smooth along with the rollers. Make sure the tabs are 90 degrees to the back of the case. Pumps are cheap. But as well as I can see yours looks normal. I'm not sure how many 727's some commentors have built here. My expertise comes from being a tech since 1977. First trans was 1978. Built many race and street trans since.
Doug
Doug
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miller
Well-Known Member
Err, had to remind myself. That's what I get for gettin' old. Have to pull the set screw, and tap the outer race out. I do mine just out of habit.
But, heck, that's me. Book shows it out. Makes sense, since it makes it alot easier to look at, and polish the cams. Unless it looks perfect, it comes out...the book talks about needs to be in good shape, and can explode. Seen pictures...
Each to your own, builder's decision.
Pump looks good? Not that outer rotor. I'd at least replace both rotors.
Besides the set screw - the outer race is staked in the case and that is one reason I was hesitant to remove it. I think I'll pull it apart and check the rollers and inner race first.
I'm going to take a closer look at the pump today. If the housing looks good I may just replace the bushing and the pump impeller parts.
Question - what bolt patter diameter flex plate would a stock 67 - 69 440 have - 10 inch or 11 inch?
I'm going to take a closer look at the pump today. If the housing looks good I may just replace the bushing and the pump impeller parts.
Question - what bolt patter diameter flex plate would a stock 67 - 69 440 have - 10 inch or 11 inch?
More problems caused to the case removing the outer over running clutch race. The outer cam seldom breaks. Either the case cracks and it spins or the tabs/rollers get bent/damaged from being slammed on engagement. Such as rev to D while rolling, no low band apply valve body being coasted in 1st and then the throttle slammed open.
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Didn't quite get through everything before the games today but made a little headway.
Took another look at the pump and except for some staining on the pump pieces they actually look pretty good. The teeth are symmetrical. I need to check clearances with a feeler gage. The main bushing in the housing doesn't look to good.
Tail housing bushing seems good and driveshaft yoke doesn't have any significant play although it does have some obvious wear. Might look for a replacement for the yoke.
Clutch drums, pressure plate, friction discs, steel discs all look real good and mic out OK. The only thing I noticed was the clearance to the snap ring on the rear drum is only about .021 inch and the shop manual spec is .037 - .060 inch (Carl Monroe quotes .025 - .045 for front and rear). I may need to look into a thinner snap ring. The front clutch pack is a 10 spring unit. I read conflicting information as to if this is a 440 unit or a 383 HP unit.
The overriding clutch rollers, springs, inner race all look fine. I'm not going to remove the outer race from the case.
I noticed a funny wear pattern on the output shaft bushing land areas where the clutch housings run. It's lightly scalloped all around the shaft area with high and low areas like roller bears had worn into it lightly. it's the same on both bushing areas on the shaft. Is this unusual?
Also, the accumulator bore is too heavily scored to be able to get out with fine sandpaper and polishing. The piston has metal sealing rings instead of rubber O-rings. OK to hone this out or should I look into a sleeve and replacement piston kit?
The other servo bores polished out fine.
Still got to look at some of the bushings. I understand the clutch hub bushing is prone to wear.
Thanks for all the help.
Took another look at the pump and except for some staining on the pump pieces they actually look pretty good. The teeth are symmetrical. I need to check clearances with a feeler gage. The main bushing in the housing doesn't look to good.
Tail housing bushing seems good and driveshaft yoke doesn't have any significant play although it does have some obvious wear. Might look for a replacement for the yoke.
Clutch drums, pressure plate, friction discs, steel discs all look real good and mic out OK. The only thing I noticed was the clearance to the snap ring on the rear drum is only about .021 inch and the shop manual spec is .037 - .060 inch (Carl Monroe quotes .025 - .045 for front and rear). I may need to look into a thinner snap ring. The front clutch pack is a 10 spring unit. I read conflicting information as to if this is a 440 unit or a 383 HP unit.
The overriding clutch rollers, springs, inner race all look fine. I'm not going to remove the outer race from the case.
I noticed a funny wear pattern on the output shaft bushing land areas where the clutch housings run. It's lightly scalloped all around the shaft area with high and low areas like roller bears had worn into it lightly. it's the same on both bushing areas on the shaft. Is this unusual?
Also, the accumulator bore is too heavily scored to be able to get out with fine sandpaper and polishing. The piston has metal sealing rings instead of rubber O-rings. OK to hone this out or should I look into a sleeve and replacement piston kit?
The other servo bores polished out fine.
Still got to look at some of the bushings. I understand the clutch hub bushing is prone to wear.
Thanks for all the help.
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oldbee
Well-Known Member
Sleeve&replacement i think; but I'm certainly no expert. Shaft picture doesn"t look that bad to me. Seem to remember seeing the same thing 'wayback'. No discernible ridges with your fingernail? Let it go. All this crap is aluminum and steel interacting.Keep going.
oldbee
Well-Known Member
Another thought- if it shifted before then just try to polish up the ridges in the accumulator bore to smooth them up a little? Not rocket science,old school, there had a to be a little tolerance built in.
I'm not too concerned about the shaft. The bushings looked fine - the shaft is just kind of strange looking but not rough.
The picture of the accumulator bore probably doesn't show how bad it is - it's pretty rough and the scratches deep - more than just catching a fingernail. I read somewhere - maybe Carl Munroe's book - that you could hone them. I'm not sure I could completely hone them out without going about 5 thousands over. A sleeve kit is about $90 and no machining is involved. The sleeve kit uses rubber o-ring seals. Why did this thing have steel piston rings? Seems like a mis-match with an aluminum case.
The picture of the accumulator bore probably doesn't show how bad it is - it's pretty rough and the scratches deep - more than just catching a fingernail. I read somewhere - maybe Carl Munroe's book - that you could hone them. I'm not sure I could completely hone them out without going about 5 thousands over. A sleeve kit is about $90 and no machining is involved. The sleeve kit uses rubber o-ring seals. Why did this thing have steel piston rings? Seems like a mis-match with an aluminum case.
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I think I'm beginning to resemble that statement.
Getting way to carried away here. The accumulator and servo bores get scratched. it's no biggie, run it. Want to worry about something? Check where the metal seal rings ride and make sure the area is not grooved from ring wear. Make sure the pump gears aren't all pitted up from debris, a little will be OK. Never measured a set of pump gears that were out of spec, even chewed up. Clutch clearance on the front clutch .012"-.015" per friction (4 friction .048"-.060"). Rear clutch not critical, .025"-.040" is plenty. Do not use a 3 friction clutch for a performance application. 3 pin planets will easily survive 800+ hp. Good valve body is critical. Proper kickdown adjustment is critical on a full auto valve body. I prefer 3.8 kickdown, though 4.2 and 5.0 have their place. Use an early thin pin servo or lock the late model thick pin with input/output thrust washers (metal style). 15 springs in the front clutch will prevent 1/2 shift overlap. Again depends on who's valve body. We regularly run 800-900Hp through mostly stock parts with good life.
Doug
Doug
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