[GMCnet] Th425 governor

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Les Burt

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Feb 13, 2014, 10:01:17 AM2/13/14
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Has anyone tried a governor from a Toro or Eldo in their coach? I'm wondering how big a difference there is in the shift points and if they are even useable to carry as a spare. I have several Toro governors and am trying to decide if it is worth the effort to have them recalibrated to the coach specs.

I am assuming that the top can needs to be cut off in order to recalibrate them.

Les Burt
Montreal
1975 Eleganza 26ft
A work in Progress


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Dennis Sexton

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Feb 13, 2014, 11:24:49 AM2/13/14
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Les Burt wrote on Thu, 13 February 2014 09:01
> Has anyone tried a governor from a Toro or Eldo in their coach? I'm wondering how big a difference there is in the shift points and if they are even useable to carry as a spare. I have several Toro governors and am trying to decide if it is worth the effort to have them recalibrated to the coach specs.
>
> I am assuming that the top can needs to be cut off in order to recalibrate them.
>
> Les Burt
> Montreal
> 1975 Eleganza 26ft


Les
Search under Wally on the photo site -- he has album on rebuilding governor and the various component differences.

Dennis
--
Dennis S
73 Painted Desert 230
Germantown, TN

anthony ezzo

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Feb 13, 2014, 10:50:05 AM2/13/14
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I think they are all the same,just the final drive ratio is noted by the color of the speedo gear.the two Jims will chime in I am sure.
--
77 455 Elaganza II and 67 Animal, Built 500 Powered Eldo

Les Burt

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Feb 13, 2014, 7:30:12 PM2/13/14
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I've seen Wally's info on governor rebuilds. I've also looked at numerous parts lists and IIRC, all these sources indicate that there are several coach specific governors with their own part numbers. What I have been unable to find is the actual difference in operation between the car and coach versions. I'm trying to find out how much of a difference there is in shift points between them.

Les Burt
Montreal
1975 Eleganza 26ft
A work in Progress

Johnny Bridges

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Feb 13, 2014, 8:00:58 PM2/13/14
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Hopefully, Manny or another of the gurus will chime in on this.... it looks to me as if the governor moves the plunger up or down based solely on road speed as seen by the speedo cable rotation speed.  If this is true, is it not a natural replacement a plunger machined to the same size lifted and or dropped by a stepper motor controlled by road speed?
 
--johnny
 


________________________________
From: Les Burt <gmc...@gmail.com>
To: "gmc...@temp.gmcnet.org" <gmc...@temp.gmcnet.org>
Sent: Thursday, February 13, 2014 7:30 PM
Subject: Re: [GMCnet] Th425 governor

Manny Trovao

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Feb 13, 2014, 8:48:26 PM2/13/14
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I actually have documentation from Hydra-Matic that they used the same part
number for GM, AJ, OJ governor and cover assembly. Meaning that for 73-74
the same part number 8627597 was used for the GM motorhome, AJ Eldorado,
and OJ Toronado.
Also the same part number 8629093 was used for the 75-78 GM motorhome, AJ
Eldorado, and OJ Toronado governor and cover assembly. They also list
8629090 for the governor assembly without the cover.
I also have a list of part numbers that don't mean anything because they
are all obsolete.


--
Manny Trovao
manny...@gmail.com
http://www.mannystransmission.biz/
Manny's Trans / Power Drive
San Jose, California
408-937-1583

Jon Roche

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Feb 13, 2014, 9:45:35 PM2/13/14
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I used a toro govorner as a spare. For a few weeks. It seemed to work the same. If the shift points were different, it was not noticable to me


--
75 palm beach
St. Cloud, MN
http://lqqkatjon.blogspot.com/

Ken Henderson

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Feb 13, 2014, 10:00:36 PM2/13/14
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Manny,

I've never heard you comment on Bill Bramlett's favorite governor mod:
Drill 5 each 1/4" holes in a "domino" or "dice" pattern through each of
the flyweights. Supposed to increase the shift speeds by 10 mph or so,
IIRC.

What do you think of the idea?

Ken H.

On Thu, Feb 13, 2014 at 8:48 PM, Manny Trovao wrote:

> I actually have documentation from Hydra-Matic that they used the same part
> number for GM, AJ, OJ governor and cover assembly. Meaning that for 73-74
> the same part number 8627597 was used for the GM motorhome, AJ Eldorado,
> and OJ Toronado.
> Also the same part number 8629093 was used for the 75-78 GM motorhome, AJ
> Eldorado, and OJ Toronado governor and cover assembly. They also list
> 8629090 for the governor assembly without the cover.
> I also have a list of part numbers that don't mean anything because they
> are all obsolete.
> --
>

Bob de Kruyff

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Feb 13, 2014, 10:10:11 PM2/13/14
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""I've never heard you comment on Bill Bramlett's favorite governor mod:
Drill 5 each 1/4" holes in a "domino" or "dice" pattern through each of
the flyweights. Supposed to increase the shift speeds by 10 mph or so,
IIRC.

What do you think of the idea?

Ken H.""

Why would you do that Ken ??
--
Bob de Kruyff
78 Eleganza
Chandler, AZ

Robert Mueller

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Feb 13, 2014, 10:36:50 PM2/13/14
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Bob,

Ken answered your question when he stated "Supposed to increase the shift speeds by 10 mph or so IIRC."

The TH-425 has a fly-weight governor, a device that was used in LOTS of propeller controls to control the pitch of the prop.

If you lighten the flyweights the governor would have to spin faster to move the pilot valve the same distance so what Ken noted
makes sense.

Oops! I just understood what you meant, Bob.

You were questioning why would you want to increase the shift points by 10 MPH? DOUH!

Regards,
Rob M.
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426



-----Original Message-----
From: Bob de Kruyff

""I've never heard you comment on Bill Bramlett's favorite governor mod:
Drill 5 each 1/4" holes in a "domino" or "dice" pattern through each of
the flyweights. Supposed to increase the shift speeds by 10 mph or so,
IIRC.

What do you think of the idea?

Ken H.""

Why would you do that Ken ??
--
Bob

Ken Henderson

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Feb 13, 2014, 10:52:38 PM2/13/14
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Some folks like to rev their engines up more. With the low end torque and
low rev ceilings of our Olds & Cad engines, I don't. But some do. Seems
to me we should have the Masters' opinions on the mod. What's yours?

Ken H.


On Thu, Feb 13, 2014 at 10:10 PM, Bob de Kruyff wrote:

>
>
> ""I've never heard you comment on Bill Bramlett's favorite governor mod:
> Drill 5 each 1/4" holes in a "domino" or "dice" pattern through each of
> the flyweights. Supposed to increase the shift speeds by 10 mph or so,
> IIRC.
>
> What do you think of the idea?
>
> Ken H.""
>
> Why would you do that Ken ??
> --
>

Bob de Kruyff

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Feb 14, 2014, 10:24:21 AM2/14/14
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""Some folks like to rev their engines up more. With the low end torque and
low rev ceilings of our Olds & Cad engines, I don't. But some do. Seems
to me we should have the Masters' opinions on the mod. What's yours?

Ken H.

""

Between the modulator, the governor and a functioning kick down switch, the trans should conform to whatever driving style you want. If you want to rev it higher, just get into the throttle. Frankly a 455 doesn't really like to rev that well--a 403 a bit more. I'm not proposing lugging, but if the systems are working it should never lug.
--
Bob de Kruyff
78 Eleganza
Chandler, AZ

anthony ezzo

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Feb 14, 2014, 10:46:04 AM2/14/14
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I will say this,My car will rip your face off and boil a tire or 2.My shift kit made not too much difference a little firmer than old lady Cadillac.but the set screw inside the vacuum modulator is the shift point setting.Some of the old Ford guys would put an alligator clip on the hose to limit suction and raise their shift points for drag racing.
I know that gear has options.Red,Blue,Black and White.
--
77 455 Elaganza II and 67 Animal, Built 500 Powered Eldo

Les Burt

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Feb 14, 2014, 11:47:08 AM2/14/14
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Ok this is getting interesting.

I aquired several switch pitch TH425 transmissions last year, so I looked up the governor P/N to see if it was compatible with our coaches. According to the literature I have access to, the SP P/N is not used in the GMCMH. Would I need to do anything with a SP governor or can I expect one to work correctly in a GMC coach without mods? I hope to go through at least 2 of the SP transmissions and upgrade them for GMCMH use.

What generated my need to ask this question is that I also have an opportunity to purchase a NOS governor with the same P/N as the SP unit. I am considering it as a spare to carry in my coach, but only if I can expect it to function correctly without alteration. It doesn't make sense to spend good money on one and then have to spend more to make it work. It is wiser to spend the money on the correct part the first time around.

I'd do the testing myself, but my coach is far from ready to be driven and the NOS governor won't be available for much longer.

Les Burt
Montreal
1975 Eleganza 26ft
A work in Progress



anthony ezzo

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Feb 14, 2014, 3:36:07 PM2/14/14
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Thats great to have a spare,even if its the wrong speedometer calibration.If it fails you just pull the old one,get all the plastic out and whack in the new one.then you will have 3 speeds again.When the gov gear fails,the speedo goes to 0 and the trans
shifts to second only.I spent $1200 on a rebuild once and all it was was the speedo gear.I know better now.
--
77 455 Elaganza II and 67 Animal, Built 500 Powered Eldo

Manny Trovao

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Feb 23, 2014, 2:19:42 PM2/23/14
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Ken,
Someone pointed out that I didn't answer your question
I missed it.
What Bill does/did is great.
I'm sure he does that because he knows that the governor is defective. It's
very time consuming.
As for increasing the shift speed, it can be done by using a spring on the
modulator valve or adjusting the modulator screw.
Once I got the information that the governors were the same for all three
makes, I saw no need to improve it <G>
99 percent of the time what I do to the governor works And that is removing
the gear, using a wire brush to clean the bore and clean and air blow the
valve. Check for the press parts for looseness.
If the customer tells me that it's not shifting, I ask to install the
governor from the take-off tranny. When i get that tranny core back, I pull
the governor out and put it aside with some others that I found defective
from visual checks. I then send them to Wally Anderson. <G>


--
Manny Trovao
manny...@gmail.com
http://www.mannystransmission.biz/
Manny's Trans / Power Drive
San Jose, California
408-937-1583

Ken Henderson

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Feb 23, 2014, 8:32:38 PM2/23/14
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Thanks for the note, Manny. I think the 'Net still wonders about the
difference between the governors for different vehicles

I think Kerry reported to you that we installed his 1-Ton last weekend.
Everything went right by the book (which I think Kerry looked at a time or
two (behind my back). :-)

Tomorrow morning I've got to be at the local hospital at 0645 for them to
operate on my left hand. I've had a progressively more annoying tendon
tightening up in the palm for years (called "Depuytren's Contracture").
That hand will have a splint on it for at least 2 weeks and be essentially
useless for a month or more, I'm told. :-( I've gotten 'most everything do
to get the coach ready for the 800 miles there, so we're still planning to
go. Wish we'd see you there.

Ken

Kosier

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Feb 23, 2014, 10:02:09 PM2/23/14
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Hey Ken,

I got a little visitation from Dupuytren's Contracture a few years ago.
You're in good enough shape that you'll have a good recovery.
My second day I slipped out to the shop cause I had a little work
waiting. When I came in, my wife accused me of doing something
because my cast got greasy. I denied it, of course. Said I just
put my hand out for balance. Before I went back for the check-up,
I peeled off a couple of layers of cast, so it would be clean.
When the Doc cut the cast off and asked if I could move my
fingers, I showed him a fist. Right away, I impressed him as
a good patient. My little finger didn't come completely straight,
but otherwise, it came out perfect. Good operation..

Gary Kosier
77 PB w/500 Cad
Newark,Oh

-----Original Message-----
From: Ken Henderson
Sent: Sunday, February 23, 2014 8:32 PM
To: gmclist
Subject: Re: [GMCnet] Th425 governor

Ken Henderson

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Feb 23, 2014, 10:30:44 PM2/23/14
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Ooops! I just replied to Manny's note, thinking it was off-net. :-(

Hope my hand goes as well. They say I'll be itching like crazy under the
splint. :-(

Ken H.


On Sun, Feb 23, 2014 at 10:02 PM, Kosier wrote:

> Hey Ken,
>
> I got a little visitation from Dupuytren's Contracture a few years ago.
> You're in good enough shape that you'll have a good recovery.
> My second day I slipped out to the shop cause I had a little work
> waiting. When I came in, my wife accused me of doing something
> because my cast got greasy.

...
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