727 unhappy

[‘66polycharger]

So we were looking to take the charger out on the fourth and after I warmed up the engine a bit I cycled gears like normal so I could check fluid before heading out. I noticed that r and d seemed a bit delayed in engaging. Left in neutral and checked fluid levels showed good. So I put in reverse and it backed out fine. When put in drive though the 727 would not engage until I gave it a little gas. After seeing this I put it away for the night. The last time I had it out (a few days prior) I did not notice anything out of the ordinary other than the engine seemed to be running a touch warmer than it had been about half way up the gauge which I figured it was just a warm evening and I had been a little spirited with the right pedal that night.
So I went to change the filter and fluid didn’t smell burned I did have a some “glitter” in the fluid and there was a small pile of metallic in one area of the pan. Of course I didn’t think to take a picture when cleaning things up. I did grab a pic of the filter and you can see where the pile of garbage was. After the filter change and adding in 4.5 quarts of fresh fluid (atf+4), adjusted bands and throttle pressure cable. The 727 now goes into r instantly again. D, 2, 1 are still another story I have maybe 10 - 20 second hesitation in forward gears. I did drive it because I could feel it fully engage for a run around the test loop which is probably about a 10 mile trip. Left it in D the entire time and did not give it a hard time. It cycled through all of the gears like it should so didn’t seem to be an issue there. Upon return home I checked to see if the hesitation to engage was still there and it was. Any ideas on what could be causing this? Another question since i had the pan off when adjusting the throttle pressure line I noticed quite a gap between the plunger and the cam. But the cam seemed to fully engage the plunger at full throttle. Is there a spec for the initial gap I have looked over checking threads? Attached is a photo of my filter (wish I’d have thought to get a pic of fluid) upper left corner had the offending pile. Dirt in the catch pan is not from the fluid. This car had sat about 35 years as far as we could tell before getting moving again this spring. I did change the filter and fresh fluid when we started driving. This filter has about 1500 miles. Metallic we found did not seem to be magnetic. I have ordered Tom Hands book to do a little more thorough reading on the 727. I was not able to find a copy of Monroe’s book that wasn’t on the pricey end but will keep the hunt on for that. Oh and the 727 is between a poly 318 2 barrel and 3.55 sure grip 8 3/4.
Thanks!
.

 

[turbine68rt]

I noticed quite a gap between the plunger and the cam. But the cam seemed to fully engage the plunger at full throttle. Is there a spec for the initial gap I have looked over checking threads?

The throttle pressure setting is done while the rod is fully compressed and inserting a .625" spacer tool between the rod and cam. Adjust the stop screw so the cam is just touching the spacer. You may also want to consider pulling the valve body for a thorough cleaning/adjusting since it's been sitting so long.

 

[Dave6T4]

That sludge in your pan is from your clutches/bands. A small amount is normal. That hesitation to engage after sitting for a while is also kinda normal, since some of the fluid in the torque converter drains back into the case. The "fix" for this is to start your car in Neutral and fast idle for a minute or so to refill the converter (will not refill in Park).
The fact that you say it still hesitates, even after freshly driven, is worrisome. I wonder if the Belleville spring that applies the clutches in the rear drum is cracked? This would make the apply piston move farther to apply the clutches, slowing down engagement. This clutch pack only calls for about .025" clearance between the last clutch plate and retainer ring, so proper clearance is critical. If the clutch pack is not fully applied, because of a cracked spring, this could account for the sludge, because the rear clutches are slipping. My "side hustle" had been rebuilding 727's for friends and acquaintences, for the last 40 years. I have seen my share of cracked Belleville springs over that time. Unfortunately, the whole transmission must come apart to repair this.

 

[‘66polycharger]

If Belleville spring I’m assuming it is probably not a good idea to putter around with the car even though shifting seems fine? I’ve not rebuilt/refreshed a transmission before but is something I would like to add to the repertoire. I have a 90 Daytona with a 604 that doesn’t appreciate OD and was hoping to practice on that one. But would prefer to keep the charger on the road so maybe it will be my first. Based on symptoms are there any other things I should look out for internally?
Thank you for specs on the throttle pressure cam. As far as cleaning out the valve body any tips for this?
The fact my flakes were non magnetic does that point to a specific spot I should be looking for damage on the inside?
Sorry for a lot of questions, very new to the inner workings of the automatic transmission but eager to learn the “magic” of it.

 

[dvw]

If letting the car idle in neutral (not park) doesn't solve the issue? I too would question the condition of the forward clutch pack (located in the rear drum). This clutch is applied imediately when any forward gear is selected. The bellevile spring releases this clutch pack. But as stated if it broke the the piston travel would be increased. The piston seals could be hard, cracked, worn causing low clutch apply pressure that would damge the clutch frictions. That will eventually lead to all forward gears being inoperative. The bands would have nothing to do with this issue.
Doug

 

[‘66polycharger]

Correct. Part of my normal start up before heading out has been to let the engine warm up to temp then I cycle the gears and set parking brake and leave in neutral for a minute before checking trans fluid and heading out. Knowing it had sat I figured it would be better to really let it warm up.
I was kind of figuring I’d be opening it up. Wishful thinking there was maybe an adjustment I had over looked. Any advice/recommendations on a kit to purchase to replace internals? Any updates/upgrades? I have no intentions of replacing the poly at this point but would like to add some power to the poly as time/money allows. Nothing crazy but would like to see it get around 300 horses. I have a dual quad intake for it on the bench but not sure I want to go with that or a bigger 2 barrel. I’m more interested in seat of the pants feel than going racing speeds.

 

[Dave6T4]

I get most of my stuff from A&A Transmissions near Indy. Their kits are pretty complete with the exception of oil pump/torque converter bushing and front drum bushing, which have to be ordered separately. Your 1966 transmission takes the narrow drum bushing and smaller diameter input shaft seal rings. These are good guys to deal with, but be sure to tell them what year transmission you are working on.
Your valve body can be taken apart and flushed out. There are a variety of balls and springs in these things, so you have to be very careful not to mix things up. This night be the time to do a mild shift kit upgrade on it. To fully disassemble a 727, some special tools may be required. When I first started to work on transmissions, I was employed by an OEM automotive parts producer, that had its own tool shop. I had some of my toolmaker buddies make up special drivers to remove bushings, etc.

 

[turbine68rt]

As far as cleaning out the valve body any tips for this?

I use brake cleaner and compressed air for the main body parts and separator plate, and virgin lacquer thinner for the valves themselves. There is a specific valve body/governor spray lube that I always use during reassembly. Always check each valve for free movement after everything is cleaned prior to reassembly.

 

[‘66polycharger]

Perfect thanks for the tips/advice everyone. Already checking out the A&A website. Hopefully receive my book this week so I can ask some better educated questions. As far as specialty tools hopefully the book gives some idea of what I would need? As of now plan will be to hopefully get most everything on the bench as far as parts and tools. Then use some vacation time and spend a week with my “mistress” as the missus likes to call the charger. Will keep you all posted when I can get the plan/time to get the ball rolling.

 

[dvw]

Trans repair isn't hard. I see you live in MI. Where are you at?
Doug

 

[Geoff 2]

Summit sell o'haul kits, different ones to choose from. Sounds like the rubber seals have gone hard from years of heat.

 

[‘66polycharger]

I’m mid Michigan about half way between Lansing and GR on the north side 96 if you are familiar with the area Portland exit. Surrounded by corn fields. Thanks I’ll check out Summit as well they have gotten a few pennies in the past few months. My manual is in the mail and I will start my reading and get this rolling.

 

[dvw]

I’m mid Michigan about half way between Lansing and GR on the north side 96 if you are familiar with the area Portland exit. Surrounded by corn fields. Thanks I’ll check out Summit as well they have gotten a few pennies in the past few months. My manual is in the mail and I will start my reading and get this rolling.

I'm familiar with Portland. My son lives in Grand Rapids. I'm in Waterford. I do hot rod/race trans work at home.
Doug

 

[‘66polycharger]

Very cool. Hopefully after this is all said and done my oldest and I will be able to add transmission amateurs to our résumés. We should be getting it up on my blocks before the weeks over and start getting exhaust and drive shaft out of the way and getting a spot cleared out so we can disassemble and keep things organized/clean. Once we get a good assessment on things I’ll be sure to add some pics to thread and get to work on getting parts in and ready to reassemble.

 

[‘66polycharger]

Welp after a hot weekend glad to say we made some progress. I have the transmission out and torn down and found the seal that started this ordeal. Lots of pieces of it through out so next some heavy cleaning. Washer on the pump looked a little beat up a long the edges too. Other than lots of friction material throughout everything else looked pretty solid. Now to start ordering parts and get to scrubbing.

 

[T Brashears]

Cope sells a nice Belleville spring

 

[‘66polycharger]

Thanks, luckily my Belleville seemed to check out okay. I have it reinstalled. Made some progress. Lots of cleaning and seals, gaskets and frictions/steels are all back in on the pump clutches. The thrust washer on my pump was not in the kit. So will be calling a local transmission guy here to see if he has one or can get me one. So far things are moving pretty smoothly as far as I can tell. So fingers crossed they really are as things start going back into the case. The frictions were only steel on rear clutch where the seal had gave so that was lot of cleaning.

 

[Dave6T4]

If you have it all apart, you could upgrade the fibre thrust washer between input and output shafts to a bronze one. Transmission shop should be able to get you one. I stick the pump gasket to the pump face with heavy grease so it does not get misaligned when trying to put the pump in.

 

[T Brashears]

That Belleville has been overheated,also check for piston movement,they wear where they ride on the spring.

 

[‘66polycharger]

I didn’t notice any discoloring on the Belleville when cleaning how can I tell it is overheated? I’ve include the best pic I had from disassembly still pretty dirty in pic. Thanks much appreciated!