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  #16  
Old 03-29-2008, 11:10 PM
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There are no servos in between the engine and trans, they will look like round covers on cylindrical protrusions on the side of the case. Think of them inside looking like a piston with a connecting rod in a bore, only the piston is flat so it only holds one O-ring or lip seal, and the connecting rod would be solidly attached, with a pointed end that would fit into a hole or groove in a band to push on the band when pressure is applied on top of the piston. There will either be counter pressure underneath the servo piston to release it or it would be springloaded underneath. I don't have a trans book so I couldn't say which one it would be for reverse. If it truly is coming from inside the converter area, you may have a fractured case (can happen from casting flaws or loose bolts) or you may have a pressure port plug that's come loose. There are small plugs in the end of some ports to cap off where the passage was drilled, and also serves as a test point to put diagnostic gauges on.
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  #17  
Old 03-30-2008, 10:22 AM
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turbobenz, the reason a seal goes out is that the manufacturers use a spring-backed neoprene seal to prevent all oil leaks, because customers hate oil leaks and will make warranty claims to correct them. The problem with the neoprene seal is that, although it seals really well when new, after a zillion heat cycles it gets hard. When it does that, it will sometimes break, and the broken end will dig into the shaft, but more often it won't break but will just cut a groove in the tail of the crankshaft, or the transmission's input shaft, as the spring drives the hard seal into the metal. When you replace a seal like that, you can press a thin metal repair sleeve over the shaft, although it is a little tricky to do and sometimes the shaft has to be turned down first. What I prefer to do, however, is to simply not quite bottom the seal out in its carrier when I press it in. The groove in the crankshaft or input shaft is only about 1/8" wide, so if you leave about that much space between the seal and its carrier when you press the seal in, the seal will be contacting the shaft slightly farther out, where the metal is still there. Some people are afraid to do this because they fear that the seal will fall out of its carrier if not bottomed out. This is not true because the only forces acting on the seal during engine operation are radial in nature.

The manufacturers could use a different seal material that would last virtually forever, at the expense of minimal leaks, but their customers would hate the leaks too much.

Now, turbobenz, I suggest that you go float up some hills (inside joke).
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  #18  
Old 03-30-2008, 06:12 PM
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Location: Nova Scotia, Canada.
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Speed sleeves for adding a new surface area to worn seal riding surfaces might be had at large truck repair places or simular. Basically a very thin tube in stainless with an interior diameter the same or marginally larger. The new seal surface is slightly larger in od but usually works out okay. Saves a lot of time,effort and money ocasionally
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  #19  
Old 03-30-2008, 11:54 PM
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Guys, we're talking about a trans pump seal here, not a crank or balancer seal. There is no shaft per se, it's just the snout of the torque converter which holds the seal, (which the input shaft actually fits inside of), which may as well just be replaced at that point rather than go thru the hassle and time of sleeving it. A reman converter can easily be had for about the same cost & guarantees you only do the job once rather than a few thousand miles later when the old converter decides to quit. I've never seen or heard of anyone wasting the effort to do that on a converter. Usually the pump seal fails either because it got hard, or because the pump bushing has become compromised and allowed the converter snout to develop a vibration or off to the side/off kilter position from excess slop. The "wearing a groove in the shaft theory" doesn't so much apply in this case, because we have to remember, the torque converter is mounted to a "flex plate". Why? Because it physically expands and contracts with speed and load/pressure, so it is constantly working back and forth in that seal, essentially preventing that ridgeline groove from happening. If one were to be able to mount a camera in there to watch it, the expansion change can actually be seen, so it's much more than the few thousandths of movement you get from an engine thrust bearing.
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  #20  
Old 04-03-2008, 02:09 AM
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Quote:
Originally Posted by retroguybilly View Post

Now, turbobenz, I suggest that you go float up some hills (inside joke).
I get it
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  #21  
Old 04-03-2008, 10:12 PM
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The front pump bushing is a pretty common wear item. When it's beat, the unit will leak out the front seal. - and i believe especially in reverse, since the reverse piston is mounted in tghe front pump housing. The good news is, the seal and bushing are easily replaced and cost less than $20 each. The bad news.......do you need to ask? However, this transmission is easier to remove than most.
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  #22  
Old 04-04-2008, 06:35 AM
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Pete-

That doesn't sound like my idea of "good news".

What happened to the OP? Did he run off and sell the car in frustration?

Rick
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  #23  
Old 04-12-2008, 01:28 AM
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Quote:
Originally Posted by rs899 View Post
What happened to the OP? Did he run off and sell the car in frustration?

Rick
Never, I'm committed for better or worse.

What did happen was i got it up on a semi-lift which I was at least able to sit under and, with one back tire off the ramp, watched as it significantly leaked in reverse. I wasn't completely convinced it didn't leak in drive but I am sure it leaked significantly more in reverse. I noticed for the first time the leak coming from behind the torque converter and thru the grated part in front of the transmission and not where i had observed it coming from while idling in the past.

Based on these observation I proceeded, under the partial guidance of someone who has done the job several times, to drop the transmission. doing the filter and seal before dropping it. when i got the torque converter out I saw the front seal was still in what looked like decent condition but r & r'ed it anyway. After taking out the front pump I replaced the O-ring, which was very hard, and the gasket. it took me the better part of two hours to get that gasket completely off the transmission. I was thinking perhaps it had been put in backwards being so stuck onto the transmission and then noticing where the side with adhesive lined up with the pump on the replacment. There was also a bunch of fluid in some of the hollow areas which were covered by the gasket. I wasn't sure if this might also indicate it had been put on backwards.

Transmission back in, filled with fluid, steady stream coming out. mildly freaked until i saw it was coming out of where the dipstick seats. the dipstick had bent forward a bit coming out and was not completely seated in a level position. out with the dipstick. a hammer and some silicon and back in, wait an hour, pray, fill again, Ok-no leaks. pray again (along with the counter lady at Popeyes Fried Chicken in Kentwood, LA-whole nother story). fire it up. looks ok, put it in reverse, no gushing, seemingly nothing. get under car, small leak coming from drivers side trans cooler banjo bolt, don't panic. tighten bolt, leak slows down but doesn't completely stop. I drive 100 miles home without incident. the major leaks have ceased, prayers have been mostly answered but it is still leaking ever so slightly from the same banjo bolt.
**advice on which way to go with this appreciated. the three options I see are: 1) don't worry about it as the leak is very slight 2)loosen line partially and let it drain, clean it with carberator cleaner, apply some silicon, retighten and let dry 3) order new set of washers, r&r existing washers knowing from experience that this bolt can be a pain in the a$$ to get back in.

An observation/question. My friend who helped me with the job and provided the space and tools to do it insisted I remove every fourth spring from the back of the pump when resealing it ( 4 in total) saying he was taught this by a transmission specialist from the dealership he used to work at. He told me why he was doing it but i forgot what he said- something about less resistence allowing the pump to work better.Has anyone heard of this or done this before?

Some screw ups. One of the cross memeber bolts gets stuck and needs to be grinded out. I find a new bolt clip and reattach-no problem. detaching/attaching the transmission dipstick got the better of me on both ends. bent on the way out taking it off too late and breaking the line just above the banjo bolt that runs out the back of the turbo by putting it back in too soon (i'd say it should be one of the first things to come off and the last to be reattached). I have a spare line thankfully and ran the car home by connecting the line to the bolt with some vacum hose. This seemed to work out OK in a pinch.

My major screw up, which i think I fixed, was messing with something I shouldn't have been bothering with in the first place. I had a spare modulator pin and wanted to get the modulator off to check on the pin (only because this had given me problems on my other wagon). Allen bolts look rusted on. On the first one I try a little too hard to remove and don't pay heed to that soft slow way it starts to move instead of that breaking feeling and before I know it I am looking with horror at a broken Allen Bolt with the head in my hand and the body still in the Modulator. I quit there messing with the modulator, drill the bolt out to a point where I can run a tap in there a decent way and get another allen bolt with an extra washer and lock washer added to sung it up. Any one else experienced this dilema/screwup before? My question here is what happens if you drill down further than the bolt extends? do you end up in the body of the transmission? I didn't want to find out the hard way.

All in all another major learing experience. I no longer hold the same fear and resistence i once did with transmissions. I also have to publicly say that i was completely inspired by nickydubs, a member from Chicago who had broken down earlier in the week, who i assisted with an extra set of hands and a hydraulic jack only as he pulled out his tranny, replaced the pump, and put it back in without having ever done the job before in less than 24 hours, on the side of the street in uptown New Orleans. and he made it back home without incident. mighty impressive.

good luck to all in your endevors
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  #24  
Old 04-13-2008, 10:23 PM
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Good going - glad to hear you jumped in and did it. If it only lasts a while, you're still ahead because next time will be easier - and you'll be able to replace that pump bushing, loosen that broken screw, etc. It is a bummer when you initially do the R&R and you have the same problem, no? BTDT and recently! You are now one of the few, the proud, the soaked in ATF!
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"Good judgement comes from experience. Experience comes from bad judgement."

listen, look, .........and duck.
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