New governor assembly for sale

G'day,

Unfortunately neither P/N 8625458 nor P/N 8626853 are listed in Parts Book 78Z for our governor. I do not know if it would work or
not.

See Parts Book 78Z, page 17-3

8627597 GOVERNOR-trans. (used w/8627428 & 8627737 trans, assy.)

8629093 GOVERNOR-trans. (used w/8629034. 8629289. 8629429 & 8629631 trans, assy.)

Regards,
Rob M.
The Pedantic Mechanic
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
USA '77 Kingsley - TZE 267V100808


-----Original Message-----
From: Gmclist [mailto:gmclist-bounces] On Behalf Of Chris S.
Sent: Friday, November 17, 2017 7:32 AM
To: gmclist
Subject: [GMCnet] New governor assembly for sale

Saw this available on Ebay... pricey but would provide as a nice on board spare:

https://www.ebay.com/itm/NOS-TH-425-Governor-for-1968-69-Oldsmobile-8625458-see-description-below/132395302212?hash=item1ed35ffd44:g
:4p8AAOSwW6BaBxvi

--
Chris S. -
77 Kingsley, 3.70 FD, mostly OEM -
S.E. Michigan
 
Rob,
I too, was told by Max Pardy the shop foreman at Buskirk’s that the Trans Governor was unique to the GMC motorhome 425 transmission. I bought a new one that I have carried for a spare for a long time and I have several that came out of a motorhome transmissions and one out of a 67 or 68 Toronado trans. I have always paired my governors with the transmission that I have had rebuilt. I don’t believe that this governor would be usable without be recalibrated for the motorhome transmission version and the motorhome transmission does have somewhat different internals. It would be best to ask Jim K or Manny on the suitability or this piece.

JR Wright
GMC Great Laker MHC
GMC Eastern States Charter Member
GMCGL Tech Editor
GMCMI
78 GMC Buskirk 30’ Stretch
1975 GMC Avion (Under Reconstruction)
Michigan

>
> G'day,
>
> Unfortunately neither P/N 8625458 nor P/N 8626853 are listed in Parts Book 78Z for our governor. I do not know if it would work or
> not.
>
> See Parts Book 78Z, page 17-3
>
> 8627597 GOVERNOR-trans. (used w/8627428 & 8627737 trans, assy.)
>
> 8629093 GOVERNOR-trans. (used w/8629034. 8629289. 8629429 & 8629631 trans, assy.)
>
> Regards,
> Rob M.
> The Pedantic Mechanic
> Sydney, Australia
> AUS '75 Avion - The Blue Streak TZE365V100428
> USA '75 Avion - Double Trouble TZE365V100426
> USA '77 Kingsley - TZE 267V100808
>
>
> -----Original Message-----
> From: Gmclist [mailto:gmclist-bounces] On Behalf Of Chris S.
> Sent: Friday, November 17, 2017 7:32 AM
> To: gmclist
> Subject: [GMCnet] New governor assembly for sale
>
> Saw this available on Ebay... pricey but would provide as a nice on board spare:
>
> https://www.ebay.com/itm/NOS-TH-425-Governor-for-1968-69-Oldsmobile-8625458-see-description-below/132395302212?hash=item1ed35ffd44:g
> :4p8AAOSwW6BaBxvi
>
> --
> Chris S. -
> 77 Kingsley, 3.70 FD, mostly OEM -
> S.E. Michigan
>
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
The governor setup really begs for some mechanical guru to figure one which runs off a stepper motor and speed sensor.

--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
 
Not much wrong with the governor. Except for that nylon gear on the end of
the shaft. Nylon makes wonderful combs and toys. Gears? Not so much.
Particularly when you drive right angle gears etc that drive speedometer
cables and cruise controls too. It just works harder than it should. Gets
tired and lays down. Kinda like us.
Jim Hupy

On Nov 17, 2017 7:07 AM, "Johnny Bridges via Gmclist" <

> The governor setup really begs for some mechanical guru to figure one
> which runs off a stepper motor and speed sensor.
>
> --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
>
 
Ill be the first to admit I carry a spare governor gear with me just in case. But would it be worth it or feasible to have a run of gears made from
metal? Like aluminum or steel?

There is probably a good reason why GM went with Nylon in the first place, but Im just wondering out loud. Seems like some place would be able to cut
a few thousand or so gears at somewhat of a reasonable price.

Sorry if this has already been asked and answered.

--
77 Royale, Rear Dry Bath. 403, 3.55 Final Drive, Lenzi goodies, Patterson carb and dizzy.
Mid Michigan
 
The plastic gears are a fusible link in a power train. When the resistance
to turning gets great enough, they fail, instead of tearing the hell out of
some very expensive and not easy to access other parts inside the
transmission case. That is the reasoning behind the plastic gears.
Jim Hupy
Salem, Or

> Ill be the first to admit I carry a spare governor gear with me just in
> case. But would it be worth it or feasible to have a run of gears made from
> metal? Like aluminum or steel?
>
> There is probably a good reason why GM went with Nylon in the first place,
> but Im just wondering out loud. Seems like some place would be able to cut
> a few thousand or so gears at somewhat of a reasonable price.
>
> Sorry if this has already been asked and answered.
>
>
> --
> 77 Royale, Rear Dry Bath. 403, 3.55 Final Drive, Lenzi goodies, Patterson
> carb and dizzy.
> Mid Michigan
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
The nylon gear is made of self lubricating nylon. It will wear much less than steel or aluminum. If you were to substitute a metal gear it would likely fail soon.

Emery Stora
77 Kingsley
Frederick, CO

>
> Ill be the first to admit I carry a spare governor gear with me just in case. But would it be worth it or feasible to have a run of gears made from
> metal? Like aluminum or steel?
>
> There is probably a good reason why GM went with Nylon in the first place, but Im just wondering out loud. Seems like some place would be able to cut
> a few thousand or so gears at somewhat of a reasonable price.
>
> Sorry if this has already been asked and answered.
>
>
> --
> 77 Royale, Rear Dry Bath. 403, 3.55 Final Drive, Lenzi goodies, Patterson carb and dizzy.
> Mid Michigan
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
Makes Perfect sense. As with most days on this forum, Thank you both for teaching me something today.

--
77 Royale, Rear Dry Bath. 403, 3.55 Final Drive, Lenzi goodies, Patterson carb and dizzy.
Mid Michigan
 
> Rob,
> I too, was told by Max Pardy the shop foreman at Buskirk's that the Trans Governor was unique to the GMC motorhome 425 transmission. I bought a
> new one that I have carried for a spare for a long time and I have several that came out of a motorhome transmissions and one out of a 67 or 68
> Toronado trans. I have always paired my governors with the transmission that I have had rebuilt. I don't believe that this governor would be
> usable without be recalibrated for the motorhome transmission version and the motorhome transmission does have somewhat different internals. It
> would be best to ask Jim K or Manny on the suitability or this piece.
>
> JR Wright
> GMC Great Laker MHC
> GMC Eastern States Charter Member
> GMCGL Tech Editor
> GMCMI
> 78 GMC Buskirk 30' Stretch
> 1975 GMC Avion (Under Reconstruction)
> Michigan

> >
> > G'day,
> >
> > Unfortunately neither P/N 8625458 nor P/N 8626853 are listed in Parts Book 78Z for our governor. I do not know if it would work or
> > not.
> >
> > See Parts Book 78Z, page 17-3
> >
> > 8627597 GOVERNOR-trans. (used w/8627428 & 8627737 trans, assy.)
> >
> > 8629093 GOVERNOR-trans. (used w/8629034. 8629289. 8629429 & 8629631 trans, assy.)
> >
> > Regards,
> > Rob M.
> > The Pedantic Mechanic
> > Sydney, Australia
> > AUS '75 Avion - The Blue Streak TZE365V100428
> > USA '75 Avion - Double Trouble TZE365V100426
> > USA '77 Kingsley - TZE 267V100808
> >
> >
> > -----Original Message-----
> > From: Gmclist [mailto:gmclist-bounces] On Behalf Of Chris S.
> > Sent: Friday, November 17, 2017 7:32 AM
> > To: gmclist
> > Subject: [GMCnet] New governor assembly for sale
> >
> > Saw this available on Ebay... pricey but would provide as a nice on board spare:
> >
> > https://www.ebay.com/itm/NOS-TH-425-Governor-for-1968-69-Oldsmobile-8625458-see-description-below/132395302212?hash=item1ed35ffd44:g
> > :4p8AAOSwW6BaBxvi
> >
> > --
> > Chris S. -
> > 77 Kingsley, 3.70 FD, mostly OEM -
> > S.E. Michigan
> >
> >
> >
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

I did not know that the GMC's TH425 was different than what is in a Toronado. We picked up a Toronado governor a while back, and have been carrying
it as our on board spare.
--
Chris S. -
77 Kingsley, 3.70 FD, mostly OEM -
S.E. Michigan
 
If you are carrying it as a spare in case of some kind of governor failure, the 425 governor from a Toro will work in a GMC, just not optimum. Not
much inside those things that can go wrong or wear out. Just the nylon gear, so that is all I carry. JWID
--
Larry
78 Royale w/500 Caddy
Menomonie, WI.
 
Several years ago, one of our now deceased gmcer members, Dan Gregg, had a
good bit of governor experience. He wrote it up and took good pictures of
the differences in internal parts between the motorhome, and passenger car
governors. Don't know if it is still on there, (the photo site) or not.
Worth a look.
Jim Hupy

If you are carrying it as a spare in case of some kind of governor
failure, the 425 governor from a Toro will work in a GMC, just not optimum.
Not
much inside those things that can go wrong or wear out. Just the nylon
gear, so that is all I carry. JWID
--
Larry
78 Royale w/500 Caddy
Menomonie, WI.

_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
> Several years ago, one of our now deceased gmcer members, Dan Gregg, had a
> good bit of governor experience. He wrote it up and took good pictures of
> the differences in internal parts between the motorhome, and passenger car
> governors. Don't know if it is still on there, (the photo site) or not.
> Worth a look.
> Jim Hupy

Some governor pics
http://www.gmcmhphotos.com/photos/g5470-governor-fail-2c-fix-and-mods.html
http://www.gmcmhphotos.com/photos/g5470-governor-fail-2c-fix-and-mods.html
Dan's governor had come loose where the yoke is supposed to be fixed to the shaft. youtube
https://youtu.be/PLzH4r7OMPI
https://youtu.be/PLzH4r7OMPI
Toro and Eldo governors will fit and function.
--
Wally Anderson
Omaha NE
75 Glenbrook
Megasquirt III injection
Bob Stone hydroBOOOOST
Manny reaction arm system
Branscombe Kelsey Hayes park brake
http://wallyandsue.blogspot.com/
 
I don't see where failing the Governor gear will protect anything inside the transmission, although it will cease shifting properly. Usually what
fails the gear is a binding speedo cable.

--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, a series of cascading failures. First thing to go is the
speedometer cable. It does not break, but the outer cable covering melts
from header heat, and seizes the inner cable from movement. The governor
tries to rotate the seized cable, it won't move, but the transmission moves
the governor gear. The plastic gear, as designed, then strips out, leaving
the rest of the gearset intact. That's the way I see it from here. I have
repaired several coaches that failed in that way, including mine.
Jim Hupy
Salem, Or
78 GMC ROYALE 403

On Nov 17, 2017 1:52 PM, "Johnny Bridges via Gmclist" <

> I don't see where failing the Governor gear will protect anything inside
> the transmission, although it will cease shifting properly. Usually what
> fails the gear is a binding speedo cable.
>
> --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
>
 
I understand that. The way the post was worded, I took it to mean failure of the gear would lead to further internal damage. By your analysis (same
as mine) it won't necessarily do so. Hi temp lube is Your Friend for the cable. You can shield it but it still is going to run fairly warm.

--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
 
> If you are carrying it as a spare in case of some kind of governor failure, the 425 governor from a Toro will work in a GMC, just not optimum. Not
> much inside those things that can go wrong or wear out. Just the nylon gear, so that is all I carry. JWID

We carry that too :) But after one governor gear failure on the road a couple of years ago, we found that it would be super quick and easy to just
pull the entire governor assembly, and pop in the spare, and go. The spare gear would need a hole drilled in it, in the proper location, and the pin
installed and cut, etc. Minor fiddling but when you're on the road (or on the side of the road), it seems like eternity.
--
Chris S. -
77 Kingsley, 3.70 FD, mostly OEM -
S.E. Michigan
 
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