First questions on my 727 rebuild journey
- Thread starter AR67GTX
- Start date
Thanks - it was a relief when I first shifted into reverse and then drive and it slipped into gear. And then when I headed down the street and saw it shift to 2nd and a bit later to 3rd it was double relief. Now I may tackle the Muncie in my old Corvette - should be a piece of cake after this.
miller
Well-Known Member
I've always adjusted my throttle pressure linkage full on, with a slight clearance. It's the end results that matter. You want the trans lever just about full in at WOT.
Not positive, since I didn't need one on my setup, but think there's an adapter on the Eddys, that's sometimes needed, to get the correct swing.
Not positive, since I didn't need one on my setup, but think there's an adapter on the Eddys, that's sometimes needed, to get the correct swing.
I bought the Mopar adaptor when I put the Edelbrock carb on - just not sure it positions the throttle pin in exactly the same position and swing dimension as the original Carter. Anyway - I guess I'll leave it this way. Seems that a bit too much line pressure would be better than not quite enough.
Ah the Muncie. Now that's a different animal. Did my first one last year. I had to make a couple of special tools. Not to bad after that. Completely different. I just finished my NV 4500 out my my Cummins dually yesterday. Also fabricate ways to take it apart. That is one heavy trans, 200lbs. Today, replacing the the head gasket. 40lbs of boost over 202K took its toll. It took a cheery picker to lift the head off.
Doug
Doug
Well the rebuild did not fix the annoying overnight converter leak down. Guess I will just be continuing to live with that. Strange I don't recall my 64 Plymouth Sport Fury suffering from that back in the 60s and I don't recall the GTX leaking down when I first purchased it. Oh well.
I think the torque converter is growing on me. At 45 - 50 it kind of like having a part throttle kick down as the engine is a bunch more response when I first goose the throttle a little. I noticed at about one third to half throttle it runs out to about 4200 rpm before shifting into 3rd now - I'm wondering if it has enough more line pressure now to cause the governor to delay shifts until a higher rpm? I know the pump impeller I put in it had quite a bit closer tolerances than the one I pulled out and the shift kit should also increase pressures. With a stock cam and most everything else I don't really want to see more than a 5000 to 5100 rpm full throttle shift point I hope.
Doug - did you try to do anything on the Muncie on the front countershaft bore in the case? After a couple decades it seems like all of them wear there and start leaking. I have mine sealed to the bellhousing with RTV but it I tear into it I would like to find someone who can machine it out and install a bushing in it to tighten things up again.
I think the torque converter is growing on me. At 45 - 50 it kind of like having a part throttle kick down as the engine is a bunch more response when I first goose the throttle a little. I noticed at about one third to half throttle it runs out to about 4200 rpm before shifting into 3rd now - I'm wondering if it has enough more line pressure now to cause the governor to delay shifts until a higher rpm? I know the pump impeller I put in it had quite a bit closer tolerances than the one I pulled out and the shift kit should also increase pressures. With a stock cam and most everything else I don't really want to see more than a 5000 to 5100 rpm full throttle shift point I hope.
Doug - did you try to do anything on the Muncie on the front countershaft bore in the case? After a couple decades it seems like all of them wear there and start leaking. I have mine sealed to the bellhousing with RTV but it I tear into it I would like to find someone who can machine it out and install a bushing in it to tighten things up again.
The case I used fit well and wasn't worn. Sealed with RTV . I got the parts from D&L, they were very knowledgeable in my opinion.
http://www.dandltransmission.com/info.html
Now on the 727. Line pressure is set by the regulator, not the pump. The shift times are governor pressure overcoming throttle pressure. If the valve body throttle pressure is raised the shift will be later.
Doug
I was just speculating that my old pump might not be putting out all it could. By regulator do you mean the throttle valve in the valve body or one of the other little shuttle valves in there. Guess I need to go read the book again.
There is a dedicated pressure regulator valve.
Doug
I think I know which one it is - seems it's next to the throttle valve - I'll study up again. So I guess that sets max possible line pressure and the throttle valve works within that range.
Climbed under the car today to see how it was doing leak-wise since I haven't seen any spots on the floor pan. Everything looked dry except there was a little fluid seeping from the cover on the bell housing. I have a hard time believing it's from the seal since it's a new seal running on a new toque converter. So probably from the vent or maybe from when I installed the converter with oil in it?? Is this maybe not unusual on a new start up?
Also, seems I remember Doug (Dvw) posting elsewhere that it's better to run the transmission a pint low (if I remember correctly). I think it was a thread dealing with converter drain back. My transmission is sitting right at 1 pint low when good and hot in neutral. Leave it at that point or fill it up?? I have a stock pan if that matters.
Also, seems I remember Doug (Dvw) posting elsewhere that it's better to run the transmission a pint low (if I remember correctly). I think it was a thread dealing with converter drain back. My transmission is sitting right at 1 pint low when good and hot in neutral. Leave it at that point or fill it up?? I have a stock pan if that matters.
miller
Well-Known Member
As long as you don't have any shift/slipping problems, a pint low, should be okay. Won't hurt to add a 1/2 pint, but you don't want it over the full mark! I've always kept mine just under.
Possible, on the fluid seepage, it took a little for the seal to seat. Usually does.
How's the trans working for ya?
Possible, on the fluid seepage, it took a little for the seal to seat. Usually does.
How's the trans working for ya?
Thanks Miller - it seems to be working well. Not sure the 2500 rpm converter was the best choice. Probably should have gone with a 2000 one - but give it some gas and it's kind of like having part throttle kick down. Otherwise working great - I love the fact it's no longer immediately shifting into second and third before I clear the intersection. Oh - converter still leaks down overnight. I guess I could try the check valve in the return line or more likely just live with it.
I went for a short ride to heat it up yesterday and looked underneath when I got back - didn't see any drip or anything on the lower edge of the bell housing. I'll keep an eye on it.
I went for a short ride to heat it up yesterday and looked underneath when I got back - didn't see any drip or anything on the lower edge of the bell housing. I'll keep an eye on it.
miller
Well-Known Member
Don't know what the deal is, with that. I've never had one leak down. Maybe I'm too stupid to know the dif! Hehe. Alway's thought the one valve in the shift body controlled that. Guess your saying it wants to slip, when you first get it going?
(I slipped a good used so-called Hemi converter into mine. One of these days, might even get to try it!)
I think maybe it must have to do with wear in a valve in the valve body. Mine all looked in good shape but possibly the casting has a bit of wear on the bore. It seems to be far from a rare issue.
Yes, taking off at part throttle there is a good deal of slip and engine roar until I ease back on the throttle - reminds me a whole lot of the automatic 68 Hemi Charger I test drove back about 1970. So I'm guessing it's not much different than the Hemi TC. The old one that was in it was really tight so the difference is sort of accentuated.
Yes, taking off at part throttle there is a good deal of slip and engine roar until I ease back on the throttle - reminds me a whole lot of the automatic 68 Hemi Charger I test drove back about 1970. So I'm guessing it's not much different than the Hemi TC. The old one that was in it was really tight so the difference is sort of accentuated.
miller
Well-Known Member
It's possible, even with a shift body, and valves, that look good. Those valves are a very close fit, and doesn't take much to make them not work the way they should. There could be other issues that cause it, that I don't know about. Of course, 'modified' parts can play hell, too, if they are not spot on.
Has to be a reason...simple, or not so simple...nature of the beast. Wouldn't worry much on it, unless it gets worst. Heck, it could even be a design flaw.
Any rate, great to hear it's operating good for you!
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