My transmission leak...

[Ken H.]

I must not have the same photo as others: The upper left corner of the one
I got is so dark that I can't distinguish ANYTHING, even after using a
photo editor to lighten it up.

Ken "Hoping You're Right" H.

> Thanks for the reply - this is a cleaned up pic:
>
> https://photos.app.goo.gl/mmxXnEbFNh75LkgBA <
> https://photos.app.goo.gl/mmxXnEbFNh75LkgBA>
>
> I think the case is OK. Just way too much baby powder! But it helped the
> process...
>
>

 

[Rob]

I was concentrating the pic on the lower section of the FD case - I'll take another (after a bit more cleaning) of the upper bolt.

But it's still leaking like a sieve. So - perhaps there is a crack there. I didn't see anywhere in the manual about sealant on those bolts - but I cannot see a source of the ATF leak anywhere other than BOLT "A".

I think I'll pull BOLT "A", clean it up and have a closer look. I'll post another pic - but the engine's hot and I've got a meeting to head to...

Thanks!

Rob
Victoria, BC
76 Royale - Rear Twins/Dry Bath

>
> I must not have the same photo as others: The upper left corner of the one
> I got is so dark that I can't distinguish ANYTHING, even after using a
> photo editor to lighten it up.
>
> Ken "Hoping You're Right" H.

 

[Rob]

I bailed on my meeting...

I pulled BOLT "A" and cleaned it up a bit. These pics might help:

https://photos.app.goo.gl/8S2ptSFUNohXYrwC8

https://photos.app.goo.gl/9WSJtUeMVApqu6fAA

I don't see/feel a crack - but who knows?

I may run it a bit with the bolt removed - since I can see much better now and would love to see where the fluid emerges from. The bolt I pulled out is longer than I expected (maybe a 1.5"?).

Rob
Victoria, BC
76 Royale - Rear Twins/Dry Bath

>
> I must not have the same photo as others: The upper left corner of the one
> I got is so dark that I can't distinguish ANYTHING, even after using a
> photo editor to lighten it up.
>
> Ken "Hoping You're Right" H.

 

[mike]

Blowing up your photo, it looks to me like the housing the bolt screws into has been welded and then peened along a crack. There are a lot of small
circles like repeated hits on the welded area with a center punch. Also, there is a line in the photo to the left of the bolt head that appears to
run between the bolt hole and the other hole. what is that? I'd check those areas closely.
--
Mike K.
'75 PB
Southeast Michigan

 

[Rob]

There are two interesting bolts, the first is BOLT "A", which is where I've seen the fluid. It's the bolt hole circled in red in this pic:

https://photos.app.goo.gl/MgtdXAhTtSYZ1oRGA

The second is BOLT "B", no obvious leak, but appears to have leaked in the past (since it was installed with some kind of semi-hard sealant). The installed bolt is circled in blue:

https://photos.app.goo.gl/H8gdVqa69eaT1LZNA

Which pic were you referring to with the center punch marks, etc...? Was it one of the above pics?

I think the little line in second pic, is just a piece of fluff!

Since I've pulled out BOLT "A" - I've not been able to get any fluid out, but as soon as it moves, I expect to see some...

Rob
Victoria, BC
76 Royale - Rear Twins/Dry Bath

>
> Blowing up your photo, it looks to me like the housing the bolt screws into has been welded and then peened along a crack. There are a lot of small
> circles like repeated hits on the welded area with a center punch. Also, there is a line in the photo to the left of the bolt head that appears to
> run between the bolt hole and the other hole. what is that? I'd check those areas closely.
> --
> Mike K.
> '75 PB
> Southeast Michigan

 

[Ken H.]

Rob,

I see no sign of a crack now that it's cleaned up. There is a SLIGHT
possibility that the transmission housing was welded where it accepts the
blue-circled bolt, but it's probably just been abraded there.

The "hard sealant" showing around that bolt is sort of strange -- I'd get
it out of there, but I doubt it will make any difference -- I don't think
either of those bolts is exposed to ATF in the case(s).

Maybe some baby powder now will help.

Good luck -- you seem to need it.

Ken H.

> There are two interesting bolts, the first is BOLT "A", which is where
> I've seen the fluid. It's the bolt hole circled in red in this pic:
>
> https://photos.app.goo.gl/MgtdXAhTtSYZ1oRGA
>
> The second is BOLT "B", no obvious leak, but appears to have leaked in the
> past (since it was installed with some kind of semi-hard sealant). The
> installed bolt is circled in blue:
>
> https://photos.app.goo.gl/H8gdVqa69eaT1LZNA
> ​...
>
>

 

[Bruce Hart]

Ken Burton,
The grommet fits into the final drive cavity and the dip stick tube fits
into the grommet.
Grommet thickness same as "o ring".

> There are two interesting bolts, the first is BOLT "A", which is where
> I've seen the fluid. It's the bolt hole circled in red in this pic:
>
> https://photos.app.goo.gl/MgtdXAhTtSYZ1oRGA
>
> The second is BOLT "B", no obvious leak, but appears to have leaked in the
> past (since it was installed with some kind of semi-hard sealant). The
> installed bolt is circled in blue:
>
> https://photos.app.goo.gl/H8gdVqa69eaT1LZNA
>
> Which pic were you referring to with the center punch marks, etc...? Was
> it one of the above pics?
>
> I think the little line in second pic, is just a piece of fluff!
>
> Since I've pulled out BOLT "A" - I've not been able to get any fluid out,
> but as soon as it moves, I expect to see some...
>
> Rob
> Victoria, BC
> 76 Royale - Rear Twins/Dry Bath
>

> >
> > Blowing up your photo, it looks to me like the housing the bolt screws
> into has been welded and then peened along a crack. There are a lot of small
> > circles like repeated hits on the welded area with a center punch.
> Also, there is a line in the photo to the left of the bolt head that
> appears to
> > run between the bolt hole and the other hole. what is that? I'd check
> those areas closely.
> > --
> > Mike K.
> > '75 PB
> > Southeast Michigan
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>

--
Bruce Hart
1976 Palm Beach
Milliken, Co
GMC=Got More Class

 

[mike]

> Ken Burton,
> The grommet fits into the final drive cavity and the dip stick tube fits
> into the grommet.
> Grommet thickness same as "o ring".
>

>
> > There are two interesting bolts, the first is BOLT "A", which is where
> > I've seen the fluid. It's the bolt hole circled in red in this pic:
> >
> > https://photos.app.goo.gl/MgtdXAhTtSYZ1oRGA
> >
> > The second is BOLT "B", no obvious leak, but appears to have leaked in the
> > past (since it was installed with some kind of semi-hard sealant). The
> > installed bolt is circled in blue:
> >
> > https://photos.app.goo.gl/H8gdVqa69eaT1LZNA
> >
> > Which pic were you referring to with the center punch marks, etc...? Was
> > it one of the above pics?
> >
> > I think the little line in second pic, is just a piece of fluff!
> >
> > Since I've pulled out BOLT "A" - I've not been able to get any fluid out,
> > but as soon as it moves, I expect to see some...
> >
> > Rob
> > Victoria, BC
> > 76 Royale - Rear Twins/Dry Bath
> >

> >>
> >> Blowing up your photo, it looks to me like the housing the bolt screws
> > into has been welded and then peened along a crack. There are a lot of small
> >> circles like repeated hits on the welded area with a center punch.
> > Also, there is a line in the photo to the left of the bolt head that
> > appears to
> >> run between the bolt hole and the other hole. what is that? I'd check
> > those areas closely.
> >> --
> >> Mike K.
> >> '75 PB
> >> Southeast Michigan
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> >
>
>
>
> --
> Bruce Hart
> 1976 Palm Beach
> Milliken, Co
> GMC=Got More Class
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

I blew up area I was referring to and posted it on photo site:
http://www.gmcmhphotos.com/photos/uploads/2934/trans.jpg

--
Mike K.
'75 PB
Southeast Michigan

 

[Rob]

Thanks again.

I added a washer (it won’t surprise me if that one was bottoming out) and some red RTV to BOLT “A” and re-installed it. I’m cautiously optimistic - but I’ve been chasing this for a while, that I’m not gonna get too excited. A drive tomorrow will tell me more...

After my trip next week - I *may* pull the lower bolt and do the same. I don’t think its leaking at all now - so I’m thinking it’s best to let sleeping dogs lie.

Rob
Victoria, BC
76 Royale - Rear Twins/Dry Bath

>
> Rob,
>
> I see no sign of a crack now that it's cleaned up. There is a SLIGHT
> possibility that the transmission housing was welded where it accepts the
> blue-circled bolt, but it's probably just been abraded there.
>
> The "hard sealant" showing around that bolt is sort of strange -- I'd get
> it out of there, but I doubt it will make any difference -- I don't think
> either of those bolts is exposed to ATF in the case(s).
>
> Maybe some baby powder now will help.
>
> Good luck -- you seem to need it.
>
> Ken H.

 

[Rob]

In the end - I couldn’t see any evidence of leakage from the base of the dipstick, so I left it alone!

Thanks.

Rob
Victoria, BC
76 Royale - Rear Twins/Dry Bath

>
> Ken Burton,
> The grommet fits into the final drive cavity and the dip stick tube fits
> into the grommet.
> Grommet thickness same as "o ring".
>
> --
> Bruce Hart
> 1976 Palm Beach
> Milliken, Co
> GMC=Got More Class

 

[Rob]

Thanks for the clarification.

I’ve had very little leakage from the transmission side of the FD-Trans connection, most of what I did find was from the speedo drive.

I had looked at several places on the transmission case and was shocked at its rough state. But having said that - if it’s not leaking, I doubt I’m gonna mess with it until it starts to!

I’m going to keep an eye on that bolt (BOLT “B”), since it appears to have caused someone issues in the past...

I’ll be heading out for a test drive soon...

Rob
Victoria, BC
76 Royale - Rear Twins/Dry Bath

>
> I blew up area I was referring to and posted it on photo site:
> http://www.gmcmhphotos.com/photos/uploads/2934/trans.jpg
>
> --
> Mike K.
> '75 PB
> Southeast Michigan

 

[johnny]

When I look at the last picture, just to the right of the cast brace, and just to the left of the right hand bolt, I see a jagged line going downwards
which sure looks like a crack to me. I chased mine with a roll of paper towels. Cleaned and dried all of it off and lapped the block. Drips
appearing on the bolts to the pan in the rear, but dry on the ledges above them (even a little bit of Dexeron will show on a paper towel. Pressed on
the pan corner with my thumb and the fluid in the seam moved a bit, indicating it was coming from the joint between the pan and the case.

--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

 

[Rob]

Thanks.

With a trip coming up - I’m hoping that a local trans shop will be able to help me out. I’m not sure what they’ll find or how long it will take, but I was really looking forward to the next couple of trips... They’ve worked on a couple of GMC MH’s recently, so I’m trying to be optimistic...

Rob
Victoria, BC
76 Royale - Rear Twins/Dry Bath

>
> When I look at the last picture, just to the right of the cast brace, and just to the left of the right hand bolt, I see a jagged line going downwards
> which sure looks like a crack to me. I chased mine with a roll of paper towels. Cleaned and dried all of it off and lapped the block. Drips
> appearing on the bolts to the pan in the rear, but dry on the ledges above them (even a little bit of Dexeron will show on a paper towel. Pressed on
> the pan corner with my thumb and the fluid in the seam moved a bit, indicating it was coming from the joint between the pan and the case.
>
> --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