TH-425 ATF Change Qty

K

Ken H.

Active member
Sep 9, 2000
19,428
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38
Somebody please refresh my memory: How much ATF should it take to refill
my Ragusa TH-425 pan? I drained it very thoroughly by letting it sit open
for several days. Then I reinstalled the pan with a rubber gasket sealed
on both sides with #1 Permatex, trying to stop the leaks.

Today, I put 2 full gallons of ATF in and just barely see a trace at the
bottom of the dipstick. I didn't think I'd need that much & will have to
violate isolation to get more -- another gallon?

TIA,

Ken "Lost Memory" H.
 
Ken,
Typically in the past if you just let the trans drain with the stock pan it
took aprox. 6 qts to refill again. so your 2 gals. may be close with the
Ragusa pan additional volume. As hindsite I always drain the tranny fluid
into a container that i can measure the fluid volume. Remember that you
can always get close tot he correct level if you have overfilled, by
removing the modulator after warming the trans .

Regards,

J.R. Wright
GMC Great Laker
GMCGL Tech Editor
GMC Eastern States
GMCMHI
TZE Zone Restorations
78 Buskirk Custom 29.5' Stretch
75 Avion (Under going Frame up Restoration)

On Wed, Apr 22, 2020 at 7:43 AM Ken Henderson via Gmclist <

> Somebody please refresh my memory: How much ATF should it take to refill
> my Ragusa TH-425 pan? I drained it very thoroughly by letting it sit open
> for several days. Then I reinstalled the pan with a rubber gasket sealed
> on both sides with #1 Permatex, trying to stop the leaks.
>
> Today, I put 2 full gallons of ATF in and just barely see a trace at the
> bottom of the dipstick. I didn't think I'd need that much & will have to
> violate isolation to get more -- another gallon?
>
> TIA,
>
> Ken "Lost Memory" H.
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
That sounds about right. If you let it drain for several days you also got some additional fluid out from torque converter leak down.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
I am afraid I won't be much help, Ken. I have the same setup that you have,
and have experienced the same problem, with the exception that I got
impatient and over filled the transmission. I have added the vent fitting
with the overflow tube on my coach. When the fluid gets warmed up, it
burped a bunch of fluid into the small catch tank I fitted to it. A couple
of times, if I recall correctly.
The real issue is the torque converter. It is impossible to tell how
much fluid remains in it after a pan removal and subsequent thorough
draining process. So, it becomes a job of, add a bit of fluid, check the
level, and repeat several times.
Some folks measure the drained fluid, and add back that amount.
Never works for me, but they use it.
Stay well my friend.
Jim Hupy
Salem, Oregon

On Wed, Apr 22, 2020, 7:43 AM Ken Henderson via Gmclist <

> Somebody please refresh my memory: How much ATF should it take to refill
> my Ragusa TH-425 pan? I drained it very thoroughly by letting it sit open
> for several days. Then I reinstalled the pan with a rubber gasket sealed
> on both sides with #1 Permatex, trying to stop the leaks.
>
> Today, I put 2 full gallons of ATF in and just barely see a trace at the
> bottom of the dipstick. I didn't think I'd need that much & will have to
> violate isolation to get more -- another gallon?
>
> TIA,
>
> Ken "Lost Memory" H.
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
> Somebody please refresh my memory: How much ATF should it take to refill my Ragusa TH-425 pan? I drained it very thoroughly by letting it sit
> open for several days. Then I reinstalled the pan with a rubber gasket sealed on both sides with #1 Permatex, trying to stop the leaks.
>
> Today, I put 2 full gallons of ATF in and just barely see a trace at the bottom of the dipstick. I didn't think I'd need that much & will have
> to
> violate isolation to get more -- another gallon?
>
> TIA,
>
> Ken "Lost Memory" H.]

Ken,

I can promise that you are low....

Way long ago when I had to work on my transmission, I drained it completely - even the converter. I do recall that I sucked about an half a gallon
out of the converter that had not drained out of the transmission. What I drained filled 3 gallon anti-freeze jugs. I bought a dozen quart bottles
to refill it and it came up a little short and this is with the standard steel pan.

I would guess you need at least 3 more.

Save what you drained to mix with acetone for penetrating oil. I still have two of those.

Matt
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan
OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit
 
Ken,
I have a Ragusa pan and just drained and new filter. My coach had been sitting in the shop since October so pretty much drained down.

I measured 9 litres of fluid came out. I've put 9 US quarts back in and its close to the level I noted on the dip stick before I drained it.

A US quart is a tad less than a litre, so once I get it out, I suspect I'll need to top it up. Sorry about the metric messing up you 'mericans!

One issue I have is the Ragusa drain plug is leaking. The 3/8" bolt does not have a flange on it to prove a good seal. Its just a hex head. The only
source I can find for a non serrated flange bolt is McMaster Carr and they don't ship to Canada.

Maybe find a fresh washer to put on your pan plug.

--
Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
 
Thanks, Everyone, for updating my memory. I'd expected 6 Q. to fill it but
I'd forgotten Ragusa's extra volume and it didn't occur to me that I might
have more than normal converter leakdown. I'll go get another gallon (at
least) tomorrow. I trust my dipstick, so I won't bother trying to warm up
the transmission for a modulator check. It may be September (if then)
before I get to drive it again. :-(

Y'All keep on stayin' safe!

Ken H.

On Wed, Apr 22, 2020 at 1:23 PM Bruce Hislop via Gmclist <

> Ken,
> I have a Ragusa pan and just drained and new filter. My coach had been
> sitting in the shop since October so pretty much drained down.
>
> I measured 9 litres of fluid came out. I've put 9 US quarts back in and
> its close to the level I noted on the dip stick before I drained it.
>
> A US quart is a tad less than a litre, so once I get it out, I suspect
> I'll need to top it up. Sorry about the metric messing up you 'mericans!
>
> One issue I have is the Ragusa drain plug is leaking. The 3/8" bolt does
> not have a flange on it to prove a good seal. Its just a hex head. The only
> source I can find for a non serrated flange bolt is McMaster Carr and they
> don't ship to Canada.
>
> Maybe find a fresh washer to put on your pan plug.
>
>
> --
> Bruce Hislop
> ON Canada
> 77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.1 ton front end
> http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
> My Staff says I never listen to them, or something like that
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Ken,
After talking with Manny, I put rubber rings o rings around the tranny bolts on my Ragusa pan. So far, the last 200 miles have been leak free.
Scott.
--
Scott Nutter
1978 Royale Center Kitchen, Patterson 455, switch pitch tranny, 3.21 final drive, Quad bags, tankless water heater, everything Lenzi. Alex Ferrera
installed MSD Atomic EFI
Houston, Texas
 
Scott,

Thanks for that suggestion, but I tried it earlier (even though I couldn't
find any bolt holes that weren't dead-ended). It didn't help me any. Even
after paint sealing the inside of the pan to prevent any ATF from migrating
through the sand-cast aluminum,
and using only RTV for a gasket, I still had a lot of leakage. Apparently
most of that was happening at the right rear where the pan flange to case
contact area is very narrow, from the state of the RTV there.

This, final, attempt has a good quality rubber gasket Permatex'd to both
the pan and the case. If this doesn't help, too bad -- I'll just drip for
the few years I possibly have left to do so.

Ken

On Wed, Apr 22, 2020 at 4:08 PM Scott Nutter via Gmclist <

> Ken,
> After talking with Manny, I put rubber rings o rings around the tranny
> bolts on my Ragusa pan. So far, the last 200 miles have been leak free.
> Scott.
> --
> Scott Nutter
> 1978 Royale Center Kitchen, Patterson 455, switch pitch tranny, 3.21 final
> drive, Quad bags, tankless water heater, everything Lenzi. Alex Ferrera
> installed MSD Atomic EFI
> Houston, Texas
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Ken ., if you can't get the drain plug to stop leaking, try a StatoSeal, available
from Pegasus Racing for a couple of bucks.
--
DAVE KING
lurker, wannabe
Toronto, Ontario, Canada
 
Dave,

I don't have any leakage from my drain plug; the flange seems to be my
source. But thanks for the hint; I'll try to remember for future use.

Ken H.

On Wed, Apr 22, 2020 at 11:26 PM Dave King via Gmclist <

> Ken ., if you can't get the drain plug to stop leaking, try a StatoSeal,
> available
> from Pegasus Racing for a couple of bucks.
> --
> DAVE KING
> lurker, wannabe
> Toronto, Ontario, Canada
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Dave King,

My Ragusa pan is leaking at the drain plug. Thanks for the StatoSeal suggestion.

The issue seems to be that it is a plain 3/8" hex bolt with a nylon washer. I should have changed the washer and it would be Ok. I'm looking for a
bolt with a smooth flange head and I'll use a new washer. Only place I've found them is at McMaster-Carr who won't ship to Canada (unless you are
buying a million bucks).

I found a magnetic one on Amazon, but its not available at this moment.

I'll keep looking.

Good news is my shifter shaft is no longer leaking. The seal for it was flattened and crumbled when I tried to remove it.

--
Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
 
Bruce If you want, order that bolt(s) whatever you and and send it to my address. I will re-post it to your Canadian address. I have done that for
quite a few Canadians.

A lot of Japanese car manufacturers, Honda in particular, use a copper washer on oil drain shoulder bolts. They state that they are to be replaced on
every oil change. Maybe use a flat copper washer on your Ragusa pan with a grooved shoulder bolt.


--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
Ken,
The oil level as you know should be checked when properly warmed as per (as
an example) X-7425, Page 7-44, end of first column under "Check and add
Fluids" and continues to the second column of this page. Other words Iif
you add fluid to the full mark when cold then the fluid will indicate an
overfilled condition when at operating temperature.

Regards,

J.R. Wright
GMC Great Laker
GMCGL Tech Editor
GMC Eastern States
GMCMHI
TZE Zone Restorations
78 Buskirk Custom 29.5' Stretch
75 Avion (Under going Frame up Restoration)
Still in Tucson practicing "Social Distancing"!

On Thu, Apr 23, 2020 at 10:16 AM Ken Burton via Gmclist <

> Bruce If you want, order that bolt(s) whatever you and and send it to my
> address. I will re-post it to your Canadian address. I have done that for
> quite a few Canadians.
>
> A lot of Japanese car manufacturers, Honda in particular, use a copper
> washer on oil drain shoulder bolts. They state that they are to be
> replaced on
> every oil change. Maybe use a flat copper washer on your Ragusa pan with
> a grooved shoulder bolt.
>
>
> --
> Ken Burton - N9KB
> 76 Palm Beach
> Hebron, Indiana
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Ken B,
Love the copper washer suggestion on the pan bolts. Would reduce the pan
bolt facing area from getting chewed up and allow the copper washer to be
the sacrificial surface instead of the pan. Great idea! Should work with
both steel and aluminum pans.

I am guessing on the size right now but here is an example from
McMaster-Carr:
https://www.mcmaster.com/93744a140

Harbor Freight offer this selection of copper washers:
https://www.harborfreight.com/80-piece-copper-washer-assortment-67526.html

Regards,

J.R. Wright
GMC Great Laker
GMCGL Tech Editor
GMC Eastern States
GMCMHI
TZE Zone Restorations
78 Buskirk Custom 29.5' Stretch
75 Avion (Under going Frame up Restoration)
Still in Tucson practicing "Social Distancing"!

> Ken,
> The oil level as you know should be checked when properly warmed as per
> (as an example) X-7425, Page 7-44, end of first column under "Check and
> add Fluids" and continues to the second column of this page. Other words
> Iif you add fluid to the full mark when cold then the fluid will indicate
> an overfilled condition when at operating temperature.
>
> Regards,
>
> J.R. Wright
> GMC Great Laker
> GMCGL Tech Editor
> GMC Eastern States
> GMCMHI
> TZE Zone Restorations
> 78 Buskirk Custom 29.5' Stretch
> 75 Avion (Under going Frame up Restoration)
> Still in Tucson practicing "Social Distancing"!
>
>
> On Thu, Apr 23, 2020 at 10:16 AM Ken Burton via Gmclist <

>
>> Bruce If you want, order that bolt(s) whatever you and and send it to my
>> address. I will re-post it to your Canadian address. I have done that for
>> quite a few Canadians.
>>
>> A lot of Japanese car manufacturers, Honda in particular, use a copper
>> washer on oil drain shoulder bolts. They state that they are to be
>> replaced on
>> every oil change. Maybe use a flat copper washer on your Ragusa pan with
>> a grooved shoulder bolt.
>>
>>
>> --
>> Ken Burton - N9KB
>> 76 Palm Beach
>> Hebron, Indiana
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
>
 
J.R.

Well I gave you the idea but not the source or size for them. I am not sure on sourcing them. If you posted links to HF and McMaster they did not
come through.

One other thought on the grooved or serrated shoulder on those bolts. If the serrations are too deep to seal properly, you could heat the washers with
a propane torch prior to installation. We do that all the time on copper washers under airplane spark plugs. It softens up the copper and allows a
better seal when tightened down.

--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
To Bruce H., Canadian Tire carry loose drain plugs. Usually in the aisle where oil filters are. Some of the
ones they carry are flanged..

DAVE KING Toronto
--
DAVE KING
lurker, wannabe
Toronto, Ontario, Canada
 
Ken B
Do you read the email version or the phorm version? I see that the links
did not come across in the Phorm version.

Here are the links again:

I am guessing on the size right now but here is an example from
McMaster-Carr:

https://www.mcmaster.com/93744a140

Harbor Freight offer this selection of copper washers:

https://www.harborfreight.com/80-piece-copper-washer-assortment-67526.html

Regards,

J.R. Wright
GMC Great Laker
GMCGL Tech Editor
GMC Eastern States
GMCMHI
TZE Zone Restorations
78 Buskirk Custom 29.5' Stretch
75 Avion (Under going Frame up Restoration)

On Fri, Apr 24, 2020 at 10:39 AM Dave King via Gmclist <

> To Bruce H., Canadian Tire carry loose drain plugs. Usually in the aisle
> where oil filters are. Some of the
> ones they carry are flanged..
>
> DAVE KING Toronto
> --
> DAVE KING
> lurker, wannabe
> Toronto, Ontario, Canada
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Still nothing JR. I see blank lines after the colons::::::

That is strange.

Oh well. Gremlins I guess.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
Dave King,

Biggest issue is the Ragusa transmission pan uses a 3/8" 16 NC bolt as the oil plug. Its not a common size oil plug.

Right now with Canadian Tire (and all other stores) you need to order on-line and CTC doesn't show anything like that on their website.

There is a Fastenal, but they are very adverse to selling to anyone who is not a large corporation, so I just avoid them.

I'm sure I can find something when things open up again.

--
Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
 
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