Valve Cover Gasket -Cork or Rubber?

[RJW]

My GMC is currently laid up in my garage with the front-end suspension and steering completely apart. I am waiting for new parts to be be delivered
and rebuildable parts (control arms) to be rebuilt by Dave Lenzi. I am fortunate that Dave lives less than an hour away from me.

I figure this is a good time to address some chronic oil leaks. These leaks seem to be coming from both valve covers and my Ragusa transmission oil
pan.

The current leaking valve cover gaskets are cork, that were glued only to the covers. When I installed them the last time, I tried to make sure the
sealing areas were flat. I tried not to over torque the bolts since the service manual says to torque them to 7 Ft Lbs. But they still leak.

Any suggestions on how to avoid valve cover leaks?

Also, my Ragusa transmission oil pan keeps leaking (seeping). Maybe I should have kept the old pan that didn't leak.

--
Richard
76 Palm Beach
SE Michigan
www.PalmBeachGMC.com


Coop Roller Cam 455, Howell TBI + EBL, 3.42 FD, Quadra Bag, Macerator, Lenzi stuff, Manny Tranny etc.

 

[john r. lebetski]

Search this forum on the Ragusa topic. “Richard RV” recently posted about this supposed porosity issue false diagnosis
--
John Lebetski
Woodstock, IL
77 Eleganza II

 

[Ken H.]

Since I baked a couple of coats of enamel inside my Ragusa pan and still
have leakage, I don't think porosity is the problem. I still haven't been
able to cure flange leaks though. Maybe RTV only?

Ken H.

On Sun, Mar 28, 2021 at 10:48 AM John R. Lebetski
wrote:

> Search this forum on the Ragusa topic. “Richard RV” recently posted about
> this supposed porosity issue false diagnosis
> --
> John Lebetski
> Woodstock, IL
> 77 Eleganza II
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>

 

[RJW]

> Search this forum on the Ragusa topic. “Richard RV” recently posted about this supposed porosity issue false diagnosis

I recall that post, but didn't pay much attention to it at the time. Since I didn't have any leaks prior to installing the Ragusa pan a few years ago
at a work rally, it may well be possible the leaking is the fault of my poor attempt at installing that pan.
--
Richard
76 Palm Beach
SE Michigan
www.PalmBeachGMC.com


Coop Roller Cam 455, Howell TBI + EBL, 3.42 FD, Quadra Bag, Macerator, Lenzi stuff, Manny Tranny etc.

 

[78 Barbi]

Hey Ken, sorry for hi-jacking your thread but would like to get in touch with you, Cheers.....Albert 78 Barbi the 23' Birchaven

 

[RJW]

> Since I baked a couple of coats of enamel inside my Ragusa pan and still
> have leakage, I don't think porosity is the problem. I still haven't been
> able to cure flange leaks though. Maybe RTV only?
>
> Ken H.

Ken,
Gee, if someone with your level of expertise with automotive stuff is having problems sealing a Ragusa pan leak, I'm Hosed!

--
Richard
76 Palm Beach
SE Michigan
www.PalmBeachGMC.com


Coop Roller Cam 455, Howell TBI + EBL, 3.42 FD, Quadra Bag, Macerator, Lenzi stuff, Manny Tranny etc.

 

[Ken H.]

Huh! I don't share your confidence! 'Specially since I've NEVER been able
to control the "automatic rust-proofing" under the GMC.

Ken H.

> > Since I baked a couple of coats of enamel inside my Ragusa pan and still
> > have leakage, I don't think porosity is the problem. I still haven't
> been
> > able to cure flange leaks though. Maybe RTV only?
> >
> > Ken H.
>
> Ken,
> Gee, if someone with your level of expertise with automotive stuff is
> having problems sealing a Ragusa pan leak, I'm Hosed!
>
> --
> Richard
> 76 Palm Beach
> SE Michigan
> www.PalmBeachGMC.com
>
>
> Coop Roller Cam 455, Howell TBI + EBL, 3.42 FD, Quadra Bag, Macerator,
> Lenzi stuff, Manny Tranny etc.
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>

 

[Matt Colie]

> My GMC is currently laid up in my garage with the front-end suspension and steering completely apart. I am waiting for new parts to be be
> delivered and rebuildable parts (control arms) to be rebuilt by Dave Lenzi. I am fortunate that Dave lives less than an hour away from me.
>
> I figure this is a good time to address some chronic oil leaks. These leaks seem to be coming from both valve covers and my Ragusa transmission
> oil pan.
>
> The current leaking valve cover gaskets are cork, that were glued only to the covers. When I installed them the last time, I tried to make sure
> the sealing areas were flat. I tried not to over torque the bolts since the service manual says to torque them to 7 Ft Lbs. But they still leak.
>
> Any suggestions on how to avoid valve cover leaks?
>
> Also, my Ragusa transmission oil pan keeps leaking (seeping). Maybe I should have kept the old pan that didn't leak.

Richard,

About your valve gear covers leaking, did you try re-torquing them? The cork based materials all have a lot of creep. I have not seen leakage from
those that I put in at the overhaul a year ago. I will try to remember to look and see what they were, I'm pretty sure that they were rubber bound
cork, but the part number does not come up in a search.

That reminds me. I owe Dave a note..... Those that have not been in his "basement" may not have an appreciation for what he does.

Matt
--
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit

 

[Ken H.]

Richard,

More as a matter of interest than anything else: Yesterday I was going
through the stack of gaskets & empty boxes on one of my storage shelves
when I came across the information sheet in one of the rocker cover
gasket boxes. It said, essentially verbatim, "In 1975 Oldsmobile quit
using rocker cover gaskets and used a liquid sealant. They also went from
using 10 hold-down bolts to 5. The enclosed gaskets can be used with
either number of bolts since the pattern for the remaining five is
unchanged...". The ... went on to warn of the narrowed sealing surface
where the bolts were removed, etc.

While their 1975 date doesn't agree with our GMC experience, maybe it's
worth investigating the possible use of only RTV to seal the rocker covers?

Ken H.

> My GMC is currently laid up in my garage with the front-end suspension and
> steering completely apart. I am waiting for new parts to be be delivered
> and rebuildable parts (control arms) to be rebuilt by Dave Lenzi. I am
> fortunate that Dave lives less than an hour away from me.
>
> I figure this is a good time to address some chronic oil leaks. These
> leaks seem to be coming from both valve covers and my Ragusa transmission
> oil
> pan.
>
> The current leaking valve cover gaskets are cork, that were glued only to
> the covers. When I installed them the last time, I tried to make sure the
> sealing areas were flat. I tried not to over torque the bolts since the
> service manual says to torque them to 7 Ft Lbs. But they still leak.
>
> Any suggestions on how to avoid valve cover leaks?
>
> Also, my Ragusa transmission oil pan keeps leaking (seeping). Maybe I
> should have kept the old pan that didn't leak.
>
> --
> Richard
> 76 Palm Beach
> SE Michigan
> www.PalmBeachGMC.com
>
>
> Coop Roller Cam 455, Howell TBI + EBL, 3.42 FD, Quadra Bag, Macerator,
> Lenzi stuff, Manny Tranny etc.
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>

 

[RJW]

> Richard,
>
> More as a matter of interest than anything else: Yesterday I was going
> through the stack of gaskets & empty boxes on one of my storage shelves
> when I came across the information sheet in one of the rocker cover
> gasket boxes. It said, essentially verbatim, "In 1975 Oldsmobile quit
> using rocker cover gaskets and used a liquid sealant. They also went from
> using 10 hold-down bolts to 5. The enclosed gaskets can be used with
> either number of bolts since the pattern for the remaining five is
> unchanged...". The ... went on to warn of the narrowed sealing surface
> where the bolts were removed, etc.
>
> While their 1975 date doesn't agree with our GMC experience, maybe it's
> worth investigating the possible use of only RTV to seal the rocker covers?
>
> Ken H.

Ken,
I noticed that today in page 305 (Engine 6A-33) of the service manual they say:

"IMPORTANT: In both production and service, a
silastic sealer, GM No. 1051435, replaces the
rubber gasket shown in Figure 20. Though the
rubber service gasket is available, the silastic
sealer makes a better oil seal. A tube wringer,
Tool J-25027, insures uniform application."

Figure 20 which follows that paragraph shows a rubber gasket. I guess it would have been a problem for them to redraw Figure 20 to not show the
gasket. If I just go with RTV alone, will I have to buy a "tube wringer, Tool J-25027, insures uniform application"? Or could I just use my hands?

https://www.tubewringer.com/

A tubewringer is something I never knew about before. It looks like you can use it to squeeze out toothpaste as well as RTV. Amazing what I learn by
having a GMC motorhome.

--
Richard
76 Palm Beach
SE Michigan
www.PalmBeachGMC.com


Coop Roller Cam 455, Howell TBI + EBL, 3.42 FD, Quadra Bag, Macerator, Lenzi stuff, Manny Tranny etc.

 

[Ken B]

Manny had me install my Ragusa pan with RTV ONLY. I have never had a leak from it.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

 

[Ken H.]

I can't imagine a tool that would be more even-flowing than a manual
squeeze; not when you factor in the varying movement speed anyway. But
I've never tried such a tool.

Ken

> > Richard,
> >
> > More as a matter of interest than anything else: Yesterday I was going
> > through the stack of gaskets & empty boxes on one of my storage shelves
> > when I came across the information sheet in one of the rocker cover
> > gasket boxes. It said, essentially verbatim, "In 1975 Oldsmobile quit
> > using rocker cover gaskets and used a liquid sealant. They also went
> from
> > using 10 hold-down bolts to 5. The enclosed gaskets can be used with
> > either number of bolts since the pattern for the remaining five is
> > unchanged...". The ... went on to warn of the narrowed sealing surface
> > where the bolts were removed, etc.
> >
> > While their 1975 date doesn't agree with our GMC experience, maybe it's
> > worth investigating the possible use of only RTV to seal the rocker
> covers?
> >
> > Ken H.
>
> Ken,
> I noticed that today in page 305 (Engine 6A-33) of the service manual they
> say:
>
> "IMPORTANT: In both production and service, a
> silastic sealer, GM No. 1051435, replaces the
> rubber gasket shown in Figure 20. Though the
> rubber service gasket is available, the silastic
> sealer makes a better oil seal. A tube wringer,
> Tool J-25027, insures uniform application."
>
> Figure 20 which follows that paragraph shows a rubber gasket. I guess it
> would have been a problem for them to redraw Figure 20 to not show the
> gasket. If I just go with RTV alone, will I have to buy a "tube wringer,
> Tool J-25027, insures uniform application"? Or could I just use my hands?
>
> https://www.tubewringer.com/
>
> A tubewringer is something I never knew about before. It looks like you
> can use it to squeeze out toothpaste as well as RTV. Amazing what I learn
> by
> having a GMC motorhome.
>
>
>
>
> --
> Richard
> 76 Palm Beach
> SE Michigan
> www.PalmBeachGMC.com
>
>
> Coop Roller Cam 455, Howell TBI + EBL, 3.42 FD, Quadra Bag, Macerator,
> Lenzi stuff, Manny Tranny etc.
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>

 

[RJW]

> > My GMC is currently laid up in my garage with the front-end suspension and steering completely apart. I am waiting for new parts to be be
> > delivered and rebuildable parts (control arms) to be rebuilt by Dave Lenzi. I am fortunate that Dave lives less than an hour away from me.
> >
> > I figure this is a good time to address some chronic oil leaks. These leaks seem to be coming from both valve covers and my Ragusa
> > transmission oil pan.
> >
> > The current leaking valve cover gaskets are cork, that were glued only to the covers. When I installed them the last time, I tried to make
> > sure the sealing areas were flat. I tried not to over torque the bolts since the service manual says to torque them to 7 Ft Lbs. But they still
> > leak.
> >
> > Any suggestions on how to avoid valve cover leaks?
> >
> > Also, my Ragusa transmission oil pan keeps leaking (seeping). Maybe I should have kept the old pan that didn't leak.
>
> Richard,
>
> About your valve gear covers leaking, did you try re-torquing them? The cork based materials all have a lot of creep. I have not seen leakage
> from those that I put in at the overhaul a year ago. I will try to remember to look and see what they were, I'm pretty sure that they were rubber
> bound cork, but the part number does not come up in a search.
>
> That reminds me. I owe Dave a note..... Those that have not been in his "basement" may not have an appreciation for what he does.
>
> Matt

Those covers have been on for about 10 years since I replaced the engine. I did try to re-torque the fasteners to no avail. Still leaking so I
thought I might start over again and try to do it right.

Yes Dave's basement is pretty interesting. Several interesting things in development. Also, he showed me some cutaways of a certain popular part
that lots of us have that actually end up reducing braking efficiency. Watch for the exposé in the next issue of the GMCMI magazine.

--
Richard
76 Palm Beach
SE Michigan
www.PalmBeachGMC.com


Coop Roller Cam 455, Howell TBI + EBL, 3.42 FD, Quadra Bag, Macerator, Lenzi stuff, Manny Tranny etc.

 

[Matt Colie]

Richard,

The synapse just fired that caused me to remember that all my build information is in the file cabinet at my left elbow. So I looked.

During my overhaul I used the FEL-PRO VS13403C which is cork (note the C). What may have made the difference is that when I have to deal with a
stamped steel cover, I often take the time to make a tool set to reshape the area around the fastener holes. I'm sure I still have the set that I
made for this but it would be what? About 80 miles to come and get that set?

Another thing I am sure will make a difference is that long ago I started using RTV with such gaskets and doing a two step assembly. After everything
is clean and straight, I will lay a bead of RTV in the cover grove and set the gasket in there and leave it alone for a short time. When I feel a lot
like it, I will put the cover on and install at least some of the fasteners as finder tight only. This causes the RTV to accommodate irregularities.
after much delay (like maybe next day), then you can snug up the fasteners. As said, cork has a lot of creep, so I would wait as long as possible
before pulling the screws to what they are supposed to be.

Matt
--
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit

 

[jim kanomata1]

If your positive of leaky trans pan, send it to Ragusa and they will
replace it.
However we have had few they did not replace and we found out the leak was
coming from areas that found its way to the pan.
Speedo drive by governor and Trans fill tube and the weep hole are always a
suspect.

> Richard,
>
> The synapse just fired that caused me to remember that all my build
> information is in the file cabinet at my left elbow. So I looked.
>
> During my overhaul I used the FEL-PRO VS13403C which is cork (note the
> C). What may have made the difference is that when I have to deal with a
> stamped steel cover, I often take the time to make a tool set to reshape
> the area around the fastener holes. I'm sure I still have the set that I
> made for this but it would be what? About 80 miles to come and get that
> set?
>
> Another thing I am sure will make a difference is that long ago I started
> using RTV with such gaskets and doing a two step assembly. After everything
> is clean and straight, I will lay a bead of RTV in the cover grove and set
> the gasket in there and leave it alone for a short time. When I feel a lot
> like it, I will put the cover on and install at least some of the
> fasteners as finder tight only. This causes the RTV to accommodate
> irregularities.
> after much delay (like maybe next day), then you can snug up the
> fasteners. As said, cork has a lot of creep, so I would wait as long as
> possible
> before pulling the screws to what they are supposed to be.
>
> Matt
> --
> Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL,
> GMCES
> Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum
> Brakes with Applied Control Arms
> SE Michigan - Near DTW - Twixt A2 and Detroit
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>

--
Jim Kanomata
Applied/GMC, Newark,CA
jimk
http://www.gmcrvparts.com
1-800-752-7502

 

[Richard RV]

> I can't imagine a tool that would be more even-flowing than a manual
> squeeze; not when you factor in the varying movement speed anyway. But
> I've never tried such a tool.

Ken,
I never understood the twist key tube dispenser either - using two hands for a one handed job is not an improvement. I ran across the pistol grip
tube dispenser some years back and it's wonderful. Makes a squeeze tube into a caulking gun and it's easy to eke out every last goober of stuff.

https://www.amazon.com/Valco-Cincinnati-Tube-Grip-Industrial-Dispenser/dp/B007IQ4XWK

I did NOT pay anything near that price! I got my replica on eBay for maybe a third of that price. Well worth the money.

RJW,
Here's what I posted about the bad rap propagation of Ragusa pans:
http://gmc.mybirdfeeder.net/GMCforum/index.php?t=msg&goto=358759

Richard
--
'77 Birchaven TZE...777;
'76 Palm Beach with 18,477 verified miles;
‘76 Edgemonte

 

[emerystora]

I also once had a dripping pan gasket. It turned out to be a cooler tube on the top left rear of the transmission. You couldn’t see it leaking at idle but the very small leak would run on top of the transmission and down a valley and run around the top of the flange of the pan.
I found that a good way to tighten it was to use a crows foot with an extension so it could be easily turned from the top with a socket wrench. I couldn’t get enough leverage reaching down with a short tubing wrench.

Emery Stora

>
> If your positive of leaky trans pan, send it to Ragusa and they will
> replace it.
> However we have had few they did not replace and we found out the leak was
> coming from areas that found its way to the pan.
> Speedo drive by governor and Trans fill tube and the weep hole are always a
> suspect.
>

>>
>> Richard,
>>
>> The synapse just fired that caused me to remember that all my build
>> information is in the file cabinet at my left elbow. So I looked.
>>
>> During my overhaul I used the FEL-PRO VS13403C which is cork (note the
>> C). What may have made the difference is that when I have to deal with a
>> stamped steel cover, I often take the time to make a tool set to reshape
>> the area around the fastener holes. I'm sure I still have the set that I
>> made for this but it would be what? About 80 miles to come and get that
>> set?
>>
>> Another thing I am sure will make a difference is that long ago I started
>> using RTV with such gaskets and doing a two step assembly. After everything
>> is clean and straight, I will lay a bead of RTV in the cover grove and set
>> the gasket in there and leave it alone for a short time. When I feel a lot
>> like it, I will put the cover on and install at least some of the
>> fasteners as finder tight only. This causes the RTV to accommodate
>> irregularities.
>> after much delay (like maybe next day), then you can snug up the
>> fasteners. As said, cork has a lot of creep, so I would wait as long as
>> possible
>> before pulling the screws to what they are supposed to be.
>>
>> Matt
>> --
>> Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL,
>> GMCES
>> Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum
>> Brakes with Applied Control Arms
>> SE Michigan - Near DTW - Twixt A2 and Detroit
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>>
>
>
> --
> Jim Kanomata
> Applied/GMC, Newark,CA
> jimk
> http://www.gmcrvparts.com
> 1-800-752-7502
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options: