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First questions on my 727 rebuild journey

AR67GTX

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OK - everyone encouraged me to dive in and rebuild my 727 so I'm started on it - it's all loose and disconnected and I will probably pull tomorrow. First couple questions:

When I removed the bolt to the block on the pass side that secures the dipstick tube I had some oil drip out and the bolt was completely covered in oil. I guess that is not a blind hole and goes into the block interior. Should all of the transmission bolts use sealer when I reinstall?

One of my main problems is the converter is leaking down overnight - which is a pretty big leak. So what are the main things I need to be looking at during disassembly to be sure this is addressed.

The other area of concern is how much whine the planetary gears produce. I know they all produce a little whine in low gear but mine seems excessive. When I took the mechanic who rebuilt the rear end in it for a ride and I came to the first stop and shift down to first - he looked startled and said what's that? So what do I need to look at as far as wear on the planetary gears? I will try to post some pictures of them when I get it apart.

Thanks for any help
 
Your on your own! joke.

I still think your drain back problem is in the valve body. If you put sealer I wouldn't use anything like Loctite. Metal chips in pan is a sign of bushing problems. I'm sure there will a flood of advice.
 
I assume your removing the converter with trans? If you leave converter on engine you'll damage pump bushing. I'd replace it anyway.
 
When you gut the trans you can spin each planet gear. If there is a bad needle bearing it will be readily apparent. I use Teflon pipe sealer on blind external holes for extra assurance,. Such as snap ring cover screws, tail shaft bolts (open holes only), kick down pivot lever plug, pressure tap plugs. Everything else is gasket only.
Doug
 
The valve body - that doesn't sound good. Are you thinking warpage or bad gasket?

Yes, the converter is un-bolted from the flex plate - pulling it with the transmission.

Kind of surprised that transmission mount bolt hole was open into the block and seeped oil - seem like a strange place for oil to be? Maybe a drain back from the head.
 
When you gut the trans you can spin each planet gear. If there is a bad needle bearing it will be readily apparent. I use Teflon pipe sealer on blind external holes for extra assurance,. Such as snap ring cover screws, tail shaft bolts (open holes only), kick down pivot lever plug, pressure tap plugs. Everything else is gasket only.
Doug

Are the needle bearings replaceable like the rollers in a transmission cluster assembly and usually included in a complete rebuild kit?

Thanks
 
No gasket in valve body just a few balls to lose and they aren't attached to you. If you have been driving the car and owned it before it started it probably a stuck valve or a weak/broken spring if I remember. Will post valve body pictures tomorrow if I don't remind me. Think I posted some on earlier post. The pump sucks fluid through valve body to pump and there is no check valve, to the and I think to converter.
 
Kind of surprised that transmission mount bolt hole was open into the block and seeped oil - seem like a strange place for oil to be?
None of the trans to block bolt holes should be open. Check for cracks.

A hint on the converter, yes needs to be pulled with the trans. You can use a small clamp on the trans housing edge, letting the clamp itself hold the converter in place when you separate motor and trans. Once the trans is out, then pull the converter off.
(Goes back in the same way!)

When you start busting down the trans, I have always pulled the pan, then the shift body. Leave the shift body together, and set aside. I've always gone through the shift body last...it's also the last part back into the trans, before the pan. Your going to have plenty of parts and pieces to play with as it is, besides the shift body. For your's, be sure to have the correct diagram for it, before taking it down.
 
Are the needle bearings replaceable like the rollers in a transmission cluster assembly and usually included in a complete rebuild kit?

Thanks
The usual repair for bad planetary needle bearings is a good used or a rebuilt unit. I suppose if you found a source and had access to the special tooling needed to R&R the planet gear inner bearing axles you could do it at home (never heard of anyone doing it though).
Mike
 
None of the trans to block bolt holes should be open. Check for cracks.
.

That's what I was thinking. It didn't appear to be leaking from the bolt hole - it was just full of oil that ran out when I removed it. Hopefully it was from an old valve cover leak that ran down there and the dipstick tube bracket funneled it in or something. I'll probe around in it a little.

Thanks
 
The usual repair for bad planetary needle bearings is a good used or a rebuilt unit. I suppose if you found a source and had access to the special tooling needed to R&R the planet gear inner bearing axles you could do it at home (never heard of anyone doing it though).
Mike

If they feel a little rough is someplace like A&A a possible source for a good used set?

Thanks
 
Yes ^^^ Also you will need a tool to compress the clutch packs to remove the snap ring holding the clutches together.Also to get to the o-ring seals.
 
I'd suggest looking for a local transmission supply house. Sure, you can go somewhere like A&A, mostly money making stuff. Unless your going hot-roddin', stock parts will work fine.

My last 727, including the $100 to get it out of the dirt, totaled $280, complete overhaul, including all my little tricks.

My experience with 'good' used parts, especially something like one of those gear sets, is hard-to-find. Wasn't it pulled for some reason?
A supply house can easily have new sets, and for the cost, worth the money. Most of those trans parts are not that much, considering what they are.
 
I was looking for new seals for speedo pinion and given seals for a Chevy that worked beautiful. My sense was the trans shop I was at thought 3-speeds were old school(?)they're all into 4-6-8 speeds anymore.
 
I hear ya oldbee, 3 speeds are for cavemen (Yes I am one).....
 
replacing the planet with another used one is the normal fix. In 30 years of building I've only seen 2 bad needle bearing in a 727. They are replaceable but not worth the time unless it is a straight cut race unit. Local supply house can fix you up. Or mail order, easy enough. Average rebuild ar0und $200 in parts.
Doug
 
I'm loading 6 pictures of valve body the third picture has the Torque converter control valve with spring. My opinion this is your problem with converter drain back. You could call this a check valve. Gummed up or spring weak or broken? Maybe miller can comment on this. If you need pictures or text of something else let me know. Only problem sometimes with text file size can be a problem.
vb.jpg
vb1.jpg
vb2.jpg
vb3.jpg
vb4.jpg
vb5.jpg
 
My opinion this is your problem with converter drain back. You could call this a check valve. Gummed up or spring weak or broken?
Could easily be. But, it's all just parts and pieces, two by two stuff. Get the right parts, and put 'em in right. First thing you must know is the year of the trans, and is it an A (small block), or B (big block). Guessing a 727B?
Much of the parts are same, some no, some are year dependent. There will be some parts, depending on year, sorta hard to find. Used parts...some good, some not, you have to decide. Just like your slightly used, whiny pinions.
The page photos Blacker posted are good, but you will need pages for the year you have!

Suggest you read some on dealing with a shift body. Must be absolutely clean. Sharp edges on the valves, and they are a close fit. No scoring/scratches on the vale bores, on and on...?

Get a copy of the 'handbook', it will help alot.
 
Well, I got the damn thing out. It would be nice if TTI would weld their H-pipe about 1-1/2 inches further to the rear. Didn't realize I would have to drop the pipes from the manifold to get the cross member mount out so that took a few more minutes.



The converter area didn't have much oil in it so I don't think the front seal was causing any issue. The converter is an 11 inch unit and the hub does have a shallow wear area around it. So - sleeve it or replace it?
(Edit - duhh, it's bushing wear, not seal wear. Can't sleeve that. I guess time for a new converter?)





End play on the input shaft is .067 inch which it looks like is in spec.

I checked numbers on this back about 15 years ago and from memory it's a 383 unit that found it's way into my GTX. I would have to dig out my book to re-check them again.



Now I have to get this thing off of my lift. I was hoping I could grab it in a bear hug and heave it off but initial attempts felt like they could be a little disastrous. I think I'll either have to call on one of my neighbors or sling it under my 4-post lift to lower it to the floor.
 
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