Home » Public Forums » GMCnet » rear main seal (replacing rear main seal)
| rear main seal [message #342369] |
Mon, 08 April 2019 12:37  |
Ken Shaffer
Messages: 89
Registered: September 2017
Location: Marion Iowa
Karma: -1
|
Member |
|
|
My old tranny and final drive are out and I discovered that I have a lot of oil build-up in the bell housing. I was told now is the time to replace the rear main seal. I stopped up to a motor builder that I use and he said removing the old rope seal is very difficult. They don't offer any "in the field" work so it looks like its up to me. He did recommend a new seal from BOP engineering. (RMS04 same one as 350 diesel.)
Can anyone shed any light on this or offer any tips/tricks?
Ken Shaffer
Marion Iowa
73 Canyon Lands, 455, Micro-level, Alum radiator, Alcoa wheels, Lenzi hubs/bearings, Howell EFI/EBL, Rostra Cruise, Custom interior
|
|
|
|
| Re: [GMCnet] rear main seal [message #342370 is a reply to message #342369] |
Mon, 08 April 2019 13:01  |
James Hupy
Messages: 6806
Registered: May 2010
Karma: -62
|
Senior Member |
|
|
If the engine is in the coach, and you are going to use the rope seal, the
pan, oil pump, splash plate, and rear main bearing must come out. There is
a trick fix for the seal. Too lengthy to describe here. Most of the time,
it is not the rope seal that leaks. It is around the main bearing cap where
it meets the block. That can be sealed up
with "Permatex, THE RIGHT STUFF" after all surfaces are surgically clean
and oil free. Be sure to also check the expansion plug on the end of the
camshaft. They often leak, too.
Jim Hupy
Salem, Oregon
78 GMC ROYALE 403
On Mon, Apr 8, 2019, 10:43 AM Ken Shaffer via Gmclist <
gmclist@list.gmcnet.org> wrote:
> My old tranny and final drive are out and I discovered that I have a lot
> of oil build-up in the bell housing. I was told now is the time to replace
> the rear main seal. I stopped up to a motor builder that I use and he
> said removing the old rope seal is very difficult. They don't offer any "in
> the field" work so it looks like its up to me. He did recommend a new
> seal from BOP engineering. (RMS04 same one as 350 diesel.)
> Can anyone shed any light on this or offer any tips/tricks?
>
>
> --
> Ken Shaffer
> Marion Iowa
> 73 Canyon Lands, 455, Manny Tranny, Custom interior
>
>
> _______________________________________________
> 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
|
|
|
|
| Re: [GMCnet] rear main seal [message #342371 is a reply to message #342370] |
Mon, 08 April 2019 13:14 |
James Hupy
Messages: 6806
Registered: May 2010
Karma: -62
|
Senior Member |
|
|
I use the seal from a 460 Ford, big block. It is a conventional
neoprene/steel 2 piece seal. But, the ropes work well if they are properly
installed.
Jim Hupy
On Mon, Apr 8, 2019, 11:01 AM James Hupy wrote:
> If the engine is in the coach, and you are going to use the rope seal, the
> pan, oil pump, splash plate, and rear main bearing must come out. There is
> a trick fix for the seal. Too lengthy to describe here. Most of the time,
> it is not the rope seal that leaks. It is around the main bearing cap where
> it meets the block. That can be sealed up
> with "Permatex, THE RIGHT STUFF" after all surfaces are surgically clean
> and oil free. Be sure to also check the expansion plug on the end of the
> camshaft. They often leak, too.
> Jim Hupy
> Salem, Oregon
> 78 GMC ROYALE 403
>
> On Mon, Apr 8, 2019, 10:43 AM Ken Shaffer via Gmclist gmclist@list.gmcnet.org> wrote:
>
>> My old tranny and final drive are out and I discovered that I have a lot
>> of oil build-up in the bell housing. I was told now is the time to replace
>> the rear main seal. I stopped up to a motor builder that I use and he
>> said removing the old rope seal is very difficult. They don't offer any "in
>> the field" work so it looks like its up to me. He did recommend a new
>> seal from BOP engineering. (RMS04 same one as 350 diesel.)
>> Can anyone shed any light on this or offer any tips/tricks?
>>
>>
>> --
>> Ken Shaffer
>> Marion Iowa
>> 73 Canyon Lands, 455, Manny Tranny, Custom interior
>>
>>
>> _______________________________________________
>> 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
|
|
|
|
| Re: [GMCnet] rear main seal [message #342372 is a reply to message #342371] |
Mon, 08 April 2019 13:39 |
Ken Shaffer
Messages: 89
Registered: September 2017
Location: Marion Iowa
Karma: -1
|
Member |
|
|
The engine is still in the coach. Tranny, final drive, oil pan, flywheel are out. I have not taken off the rear bearing cap yet. How will I be able to tell if the old seal is bad or if the oil is getting between the block and the main bearing cap? The seal my local builder recommended was also a neoprene/steel set. So if I replace the old seal, I will use your recommendation as well. I sure hope the seal is good and your Permatex trick would work. I just hate to be right there, not replace it and regret it. Hopefully I will have some clarity once I get the bearing cap off. Thank you Jim!
Ken Shaffer
Marion Iowa
73 Canyon Lands, 455, Micro-level, Alum radiator, Alcoa wheels, Lenzi hubs/bearings, Howell EFI/EBL, Rostra Cruise, Custom interior
|
|
|
|
| Re: [GMCnet] rear main seal [message #342373 is a reply to message #342372] |
Mon, 08 April 2019 13:49 |
James Hupy
Messages: 6806
Registered: May 2010
Karma: -62
|
Senior Member |
|
|
Ken, call me @5zero3 nine31fourtynine88 in a couple of hours. I am on my
way home from the hospital. I will walk you through it. Easier on my phone.
Jim Hupy
On Mon, Apr 8, 2019, 11:44 AM Ken Shaffer via Gmclist <
gmclist@list.gmcnet.org> wrote:
> The engine is still in the coach. Tranny, final drive, oil pan, flywheel
> are out. I have not taken off the rear bearing cap yet. How will I be able
> to tell if the old seal is bad or if the oil is getting between the block
> and the main bearing cap? The seal my local builder recommended was also a
> neoprene/steel set. So if I replace the old seal, I will use your
> recommendation as well. I sure hope the seal is good and your Permatex
> trick would
> work. I just hate to be right there, not replace it and regret it.
> Hopefully I will have some clarity once I get the bearing cap off. Thank
> you
> Jim!
> --
> Ken Shaffer
> Marion Iowa
> 73 Canyon Lands, 455, Manny Tranny, Custom interior
>
>
> _______________________________________________
> 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
|
|
|
|
Goto Forum:
Current Time: Sun Sep 22 03:41:58 CDT 2024
Total time taken to generate the page: 0.02599 seconds
|
GMCforum
Search
Help
Register
Login
Home
