Transmissioon Follies Redux

J

johnny

New member
May 10, 2011
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Mark and Jerry and Chuck helped me get the busted transmission out and the Manny rebuild I got from Ken H in at Chuck's shop. It did not operate
correctly on the test drive. Starts in second unless you pull it into low, shifts to second immediately you shift to drive, never shifts to third.
At least up to freeway speed it never shifts to third. Linkage is correct, has a detent at each stop, Park locks it. Conversation with Manny led to
checking the modulator - which was is the same as the removed trans, the pin is in place. A governor swap is in the offing, if that doesn't mitigate
the problem there's a local guy who's 'up' on the 425. He's willing to swap valve bodies if we pull the pan on both so he can get at them and look
for problems in the casting or something not right. If all else fails, out it comes yet again, and I'll probably get clutches and seals put in the
last one.
I've a shop in Griffin run by a 30 year friend who knows 400s and stock 425s. Part of my conversation with Manny was, if this gent is interested,
I'll have him call Manny and get the lowdown on what's done how to make a THM425 into a TZE transmission. We might end up with a guru on this side of
the Mississippi. He (Manny) said the cores aren't worth the shipping to the Left Coast. I got the im[pression he'll build them as long as he has
hard parts (which ain't long) but purely in his home shop. The travelling circus is pretty much over.
In the interim, a washer leak has me looking at about 30 running feet of gyp board soaked which I have to remove and replace. When it rains...

--johnny
--
76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
"I forgive them all, save those who hurt the dogs. They must answer to me in hell" - ol Andy, paraphrased
 
Johnny "Black Cloud",

Sorry to hear about your latest adventure!

Ken H.

On Sat, Jun 9, 2018 at 8:53 AM Johnny Bridges via Gmclist <

> Mark and Jerry and Chuck helped me get the busted transmission out and the
> Manny rebuild I got from Ken H in at Chuck's shop. It did not operate
> correctly on the test drive. Starts in second unless you pull it into
> low, shifts to second immediately you shift to drive, never shifts to
> third.
> At least up to freeway speed it never shifts to third. Linkage is
> correct, has a detent at each stop, Park locks it. Conversation with Manny
> led to
> checking the modulator - which was is the same as the removed trans, the
> pin is in place. A governor swap is in the offing, if that doesn't mitigate
> the problem there's a local guy who's 'up' on the 425. He's willing to
> swap valve bodies if we pull the pan on both so he can get at them and look
> for problems in the casting or something not right. If all else fails,
> out it comes yet again, and I'll probably get clutches and seals put in the
> last one.
> I've a shop in Griffin run by a 30 year friend who knows 400s and stock
> 425s. Part of my conversation with Manny was, if this gent is interested,
> I'll have him call Manny and get the lowdown on what's done how to make a
> THM425 into a TZE transmission. We might end up with a guru on this side of
> the Mississippi. He (Manny) said the cores aren't worth the shipping to
> the Left Coast. I got the im[pression he'll build them as long as he has
> hard parts (which ain't long) but purely in his home shop. The travelling
> circus is pretty much over.
> In the interim, a washer leak has me looking at about 30 running feet of
> gyp board soaked which I have to remove and replace. When it rains...
>
> --johnny
> --
> 76 26' Eleganza(?) with beaucoup mods and add - ons.
> Braselton, Ga.
> "I forgive them all, save those who hurt the dogs. They must answer to me
> in hell" - ol Andy, paraphrased
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Yeah, I feel like Joe Btflsk from L'il Abner.

--johnny
--
76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
"I forgive them all, save those who hurt the dogs. They must answer to me in hell" - ol Andy, paraphrased
 
Two shot hoses, < 50 scoots. Hour to take it apart hour to reassemble, ten minutes to dothe hoses. GMC-esque it is,. I figure they'll be locally
available Monday.

--johnny

--
76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
"I forgive them all, save those who hurt the dogs. They must answer to me in hell" - ol Andy, paraphrased
 
> Mark and Jerry and Chuck helped me get the busted transmission out and the Manny rebuild I got from Ken H in at Chuck's shop. A governor swap
> is in the offing, if that doesn't mitigate the problem there's a local guy who's 'up' on the 425.
> --johnny

Johnny,

I am betting governor. Cases are getting worn. Governors are old. Polished steel shaft spinning in an aluminum case. I am thinking cases are wallowing
out. Mine started in 2nd. Governor fixed that, but it still can be undecided when launching at times. I am getting so I pull it into low out of habit.
Pressure is 2X which seems good for clutches in L & S. Just my 2 cents.

I don't think the GM engineers thought the trans built for a 4.5K lb car would be pulling motorhomes 40 years later.

--johnny [/quote]

--
'74 Eleganza, SE, Howell + EBL
Best Wishes,
George
 
I'm with george, that it is the Govornor.
Ours is a rebuilt and tested unit, might be procy, but it works.

On Sat, Jun 9, 2018 at 12:42 PM, George Beckman
wrote:

> > Mark and Jerry and Chuck helped me get the busted transmission out and
> the Manny rebuild I got from Ken H in at Chuck's shop. A governor swap
> > is in the offing, if that doesn't mitigate the problem there's a local
> guy who's 'up' on the 425.
> > --johnny
>
> Johnny,
>
>
> I am betting governor. Cases are getting worn. Governors are old. Polished
> steel shaft spinning in an aluminum case. I am thinking cases are wallowing
> out. Mine started in 2nd. Governor fixed that, but it still can be
> undecided when launching at times. I am getting so I pull it into low out
> of habit.
> Pressure is 2X which seems good for clutches in L & S. Just my 2 cents.
>
> I don't think the GM engineers thought the trans built for a 4.5K lb car
> would be pulling motorhomes 40 years later.
>
> --johnny [/quote]
>
> --
> '74 Eleganza, SE, Howell + EBL
> Best Wishes,
> George
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>

--
Jim Kanomata
Applied/GMC, Newark,CA
jimk
http://www.appliedgmc.com
1-800-752-7502
 
Thanks, we have a working one in the transmission that was taken out.

--johnny
--
76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
"I forgive them all, save those who hurt the dogs. They must answer to me in hell" - ol Andy, paraphrased
 
Johnny,

I'm assuming the coach is still at Chuck's place? If you need any tool holding help just gimme another holler.

My Cocker got stitched up at the vet and he's OK now, just a little doped up,

Jerry
--
Jerry Sitzlar..... 77 Eleganza II, Twin bed, dry bath......
Lenoir City, TN
 
I'm glad the dog's OK. I'll let you know, I'll get back as soon as I get the leaky washer healed and the floor dried and a ton of backed up laundry
done. Chuck says some of the headers have room to get the governor out without removing the header, this looks like one - at any rate the front tubes
go over, not under. I'll let you know.

thanks,

--johnny
--
76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
"I forgive them all, save those who hurt the dogs. They must answer to me in hell" - ol Andy, paraphrased
 
I'll add, Manny called and said he had to use untested governors in some of the Americus builds, this may be one. We've a known good governor in the
one we removed, so >if< that's the problem - and everything points to it - we ought to be good to go.
I'm still concerned about why the last one failed, there's no fluid on the toad.. you'd expect to either see a fog of exhaust )failed modulator which
pulls fluid into the intake) or a coating of ATF on whatev er's behind. Oh well.

--johnny
--
76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
"I forgive them all, save those who hurt the dogs. They must answer to me in hell" - ol Andy, paraphrased
 
The washing machine has worked flawlessly for several dyas, so it's considered healed. Doctor's and vet's appointments have been mety. This week is
the move. Probably Tuesday but not yet firmed up.

--johnny
--
76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
"I forgive them all, save those who hurt the dogs. They must answer to me in hell" - ol Andy, paraphrased
 
(Paul Harvey voice) The REST of the story. We took the governor out of the failed transmission and put it in the one in the coach. Voila! Works
well. New vacuum line and modulator have a bit higher shift points at partial throttle, likely due to the somewhat radical cam. Anyway, worked well
on an extended test drive, other than a bit f a drip of fluid. Checked the pan bolts all at or near the book 12 ft. lbs. There's a weep at the rear
drivers side of the pan,at the corner between the bolts. I drove it home early this morning to beat the heat and Atlanta traffic woes. It dripped a
pint of fluid, replaced a half at a time at each fuel stop. I will consult Manny over what next to do, either one of the aluminum pans or put this
one one a flat table and get it flat. We'll see.
I brought the toasted transmission home, I'll probably give it to Matt Garrett to build, and ask him to consult Manny as to what might be different
from the run-of-the-mill THM425s he's used to.

Gadsden next!

--johnny
--
76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
"I forgive them all, save those who hurt the dogs. They must answer to me in hell" - ol Andy, paraphrased
 
Johnny, that modulator may be adjustable. If it is, in the hose barb, there
is an Allen wrench fitting that preloads the diaphram spring that the
vacuum pulls against. The tighter you tighten the spring, the more vacuum
required to move the diaphram. Can't remember exactly if tightening it
raises or lowers the shift points, but trial and error will settle that.
Also, the metal tube that supplies vacuum has a restriction that sometimes
becomes plugged up with crud and that will also affect the performance of
the modulator. Worth blowing out with compressed air to verify.
Jim Hupy

On Wed, Jun 20, 2018, 10:05 AM Johnny Bridges via Gmclist <

> (Paul Harvey voice) The REST of the story. We took the governor out of
> the failed transmission and put it in the one in the coach. Voila! Works
> well. New vacuum line and modulator have a bit higher shift points at
> partial throttle, likely due to the somewhat radical cam. Anyway, worked
> well
> on an extended test drive, other than a bit f a drip of fluid. Checked
> the pan bolts all at or near the book 12 ft. lbs. There's a weep at the
> rear
> drivers side of the pan,at the corner between the bolts. I drove it home
> early this morning to beat the heat and Atlanta traffic woes. It dripped a
> pint of fluid, replaced a half at a time at each fuel stop. I will
> consult Manny over what next to do, either one of the aluminum pans or put
> this
> one one a flat table and get it flat. We'll see.
> I brought the toasted transmission home, I'll probably give it to Matt
> Garrett to build, and ask him to consult Manny as to what might be different
> from the run-of-the-mill THM425s he's used to.
>
> Gadsden next!
>
> --johnny
> --
> 76 26' Eleganza(?) with beaucoup mods and add - ons.
> Braselton, Ga.
> "I forgive them all, save those who hurt the dogs. They must answer to me
> in hell" - ol Andy, paraphrased
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Great news Johnny!

Sully
Bellevue

On Wed, Jun 20, 2018 at 10:05 AM Johnny Bridges via Gmclist <

> (Paul Harvey voice) The REST of the story. We took the governor out of
> the failed transmission and put it in the one in the coach. Voila! Works
> well. New vacuum line and modulator have a bit higher shift points at
> partial throttle, likely due to the somewhat radical cam. Anyway, worked
> well
> on an extended test drive, other than a bit f a drip of fluid. Checked
> the pan bolts all at or near the book 12 ft. lbs. There's a weep at the
> rear
> drivers side of the pan,at the corner between the bolts. I drove it home
> early this morning to beat the heat and Atlanta traffic woes. It dripped a
> pint of fluid, replaced a half at a time at each fuel stop. I will
> consult Manny over what next to do, either one of the aluminum pans or put
> this
> one one a flat table and get it flat. We'll see.
> I brought the toasted transmission home, I'll probably give it to Matt
> Garrett to build, and ask him to consult Manny as to what might be different
> from the run-of-the-mill THM425s he's used to.
>
> Gadsden next!
>
> --johnny
> --
> 76 26' Eleganza(?) with beaucoup mods and add - ons.
> Braselton, Ga.
> "I forgive them all, save those who hurt the dogs. They must answer to me
> in hell" - ol Andy, paraphrased
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
> Johnny, that modulator may be adjustable. If it is, in the hose barb, there
> is an Allen wrench fitting that preloads the diaphram spring that the
> vacuum pulls against. The tighter you tighten the spring, the more vacuum
> required to move the diaphram. Can't remember exactly if tightening it
> raises or lowers the shift points, but trial and error will settle that.
> Also, the metal tube that supplies vacuum has a restriction that sometimes
> becomes plugged up with crud and that will also affect the performance of
> the modulator. Worth blowing out with compressed air to verify.
> Jim Hupy

Jim, At what speeds are the preferred shift points (under light load)

Thanks,
--
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
Solar battery charging. GMCSJ and GMCMI member
 
Kinda personal preferences, but, 1 - 2 shift about 8 - 10 mph on light
throttle, 18 - 24 or so on the 2 - 3 shift. If you are at wide open
throttle, then the flyweights in the governor forces the upshifts at a much
higher speed. Varies a bit with the individual governors and final drive
gearing.
Jim Hupy

> > Johnny, that modulator may be adjustable. If it is, in the hose barb,
> there
> > is an Allen wrench fitting that preloads the diaphram spring that the
> > vacuum pulls against. The tighter you tighten the spring, the more vacuum
> > required to move the diaphram. Can't remember exactly if tightening it
> > raises or lowers the shift points, but trial and error will settle that.
> > Also, the metal tube that supplies vacuum has a restriction that
> sometimes
> > becomes plugged up with crud and that will also affect the performance of
> > the modulator. Worth blowing out with compressed air to verify.
> > Jim Hupy
>
>
> Jim, At what speeds are the preferred shift points (under light load)
>
> Thanks,
> --
> Carl Stouffer
> '75 ex Palm Beach
> Tucson, AZ.
> Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive,
> Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American
> Eagles,
> Solar battery charging. GMCSJ and GMCMI member
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Thanks. Mine might be set a little high (more like 30 for the 2-3 shift)

> Kinda personal preferences, but, 1 - 2 shift about 8 - 10 mph on light
> throttle, 18 - 24 or so on the 2 - 3 shift. If you are at wide open
> throttle, then the flyweights in the governor forces the upshifts at a much
> higher speed. Varies a bit with the individual governors and final drive
> gearing.
> Jim Hupy
>

>

> >> Johnny, that modulator may be adjustable. If it is, in the hose barb,
> > there
> >> is an Allen wrench fitting that preloads the diaphram spring that the
> >> vacuum pulls against. The tighter you tighten the spring, the more vacuum
> >> required to move the diaphram. Can't remember exactly if tightening it
> >> raises or lowers the shift points, but trial and error will settle that.
> >> Also, the metal tube that supplies vacuum has a restriction that
> > sometimes
> >> becomes plugged up with crud and that will also affect the performance of
> >> the modulator. Worth blowing out with compressed air to verify.
> >> Jim Hupy
> >
> >
> > Jim, At what speeds are the preferred shift points (under light load)
> >
> > Thanks,
> > --
> > Carl Stouffer
> > '75 ex Palm Beach
> > Tucson, AZ.
> > Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive,
> > Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American
> > Eagles,
> > Solar battery charging. GMCSJ and GMCMI member
> >
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> >
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

--
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
Solar battery charging. GMCSJ and GMCMI member
 
I put new hose and cleaned the line when we put it inthe other week. I suspect the amount of cam keeps the MAP down a bit over stock. I shall fiodle
when the leak is corrected.

In the meantimes, I left M
 
Update -
The transmission goes to Garrett tomorrow to be repaired. Mat has agreed to give Manny a call and hear what differences he (Manny) does with the
THM425 vs stock for a Toro or Eldo. George Z talks like he might come along and give advice also. Keep watching this space.

--johnny
--
76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
"I forgive them all, save those who hurt the dogs. They must answer to me in hell" - ol Andy, paraphrased
 
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