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pcv/breather [message #108879] Sat, 18 December 2010 17:55 Go to next message
RadioActiveGMC is currently offline  RadioActiveGMC   United States
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Thanks to the forum I know realize that my pcv valve and breather are on the wrong valve covers. I'll correct that. Of course since I'm a "questioner" having the backwards, what would it do?

***"Gettin There"-1973 23' Sequoia- Michael, Onans smell, "Go solar/wind power!"
Re: [GMCnet] pcv/breather [message #108883 is a reply to message #108879] Sat, 18 December 2010 18:30 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
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On Dec 18, 2010, at 4:55 PM, Michael wrote:

>
>
> Thanks to the forum I know realize that my pcv valve and breather are on the wrong valve covers. I'll correct that. Of course since I'm a "questioner" having the backwards, what would it do?
> --
> 1973 23' Sequoia-
> Michael, Casa Grande, AZ

For one thing, your PCV valve is a Positive Crankcase Ventilator and without it being hooked up to the carb it is not ventalating the crankcase.
You may likely smell fumes from your engine since the breather filter is not hooked up to your air intake either.

Other than that no harm done.

Emery Stora
77 Kingsley
Santa Fe, NM


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Re: pcv/breather [message #108888 is a reply to message #108879] Sat, 18 December 2010 19:14 Go to previous messageGo to next message
RadioActiveGMC is currently offline  RadioActiveGMC   United States
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hummm fume smells are on the decline but Im really going to make sure the breather is taken off and routed into the air cleaner. I already have a port for it to go into.
Im pretty excited to find all these issues and one by one start to correct them.


***"Gettin There"-1973 23' Sequoia- Michael, Onans smell, "Go solar/wind power!"
Re: [GMCnet] pcv/breather [message #108916 is a reply to message #108888] Sat, 18 December 2010 22:01 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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Michael, because it is so close to Christmas and I perhaps am a little too
filled with the "Christmas spirits" it occurred to me that perhaps someone
installed your engine backwards thereby reversing the valve covers. <Grin>.
On some, but not all, 455 Oldsmobile valve covers, the stamped out holes in
the covers are different to allow for the Positive crankcase valve (PCV)
rubber boot to be installed in the Passenger side valve cover while the
Drivers side cover housed the boot that connects the PVC pipe to the air
cleaner. The two boots look similar on first glance, but I believe that they
are pointed differently. If you are lucky enough to have identical valve
covers, it is a simple enough job to change the boots from side to side. If
however, you are not using the stock carb and air cleaner, then the PCV pipe
won't have anywhere to connect to. The actual PVC valve has a tiny spring
loaded disc that alternately opens and closes with various vacuum/pressure
differences to purge the crankcase of any combustion byproducts that gets
past the worn rings. The air pipe on the drivers side supplies the crankcase
with a clean supply of air to facilitate the valve. I have never studied
this closely enough to know if reversing the covers as yours are is
problematical or not. Perhaps Emery or Steven has more info on this. I have
done enough of these engines that I always check when I am installing the
covers to make sure I don't do that.
Jim Hupy
Salem, Or
78 Royale 403

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Re: [GMCnet] pcv/breather [message #108936 is a reply to message #108916] Sun, 19 December 2010 06:52 Go to previous messageGo to next message
Steven Ferguson is currently offline  Steven Ferguson   United States
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Good explanation Jim.
I think the holes are the same in both valve covers, it's the boots, or
grommets, that are different. I've never seen a GM engine that didn't have
the filtered air supply on the L valve cover and the PCV on the R one. I
have seen a lot of guys who use push in type breathers but I guess that is
because they like the smell and fumes.

On Sat, Dec 18, 2010 at 9:01 PM, James Hupy <jamesh1296@gmail.com> wrote:

> Michael, because it is so close to Christmas and I perhaps am a little too
> filled with the "Christmas spirits" it occurred to me that perhaps someone
> installed your engine backwards thereby reversing the valve covers. <Grin>.
> On some, but not all, 455 Oldsmobile valve covers, the stamped out holes in
> the covers are different to allow for the Positive crankcase valve (PCV)
> rubber boot to be installed in the Passenger side valve cover while the
> Drivers side cover housed the boot that connects the PVC pipe to the air
> cleaner. The two boots look similar on first glance, but I believe that
> they
> are pointed differently. If you are lucky enough to have identical valve
> covers, it is a simple enough job to change the boots from side to side. If
> however, you are not using the stock carb and air cleaner, then the PCV
> pipe
> won't have anywhere to connect to. The actual PVC valve has a tiny spring
> loaded disc that alternately opens and closes with various vacuum/pressure
> differences to purge the crankcase of any combustion byproducts that gets
> past the worn rings. The air pipe on the drivers side supplies the
> crankcase
> with a clean supply of air to facilitate the valve. I have never studied
> this closely enough to know if reversing the covers as yours are is
> problematical or not. Perhaps Emery or Steven has more info on this. I have
> done enough of these engines that I always check when I am installing the
> covers to make sure I don't do that.
> Jim Hupy
> Salem, Or
> 78 Royale 403
>
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Steve Ferguson
Sierra Vista, AZ
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Re: pcv/breather [message #108962 is a reply to message #108879] Sun, 19 December 2010 10:37 Go to previous messageGo to next message
RadioActiveGMC is currently offline  RadioActiveGMC   United States
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Only cause I need the book "gmc for dummies" I'm still guessing after everything that is said I need to switch the pcv valve to the passenger side still.
On the drivers side I'm going to take off the valve cover breather and install a hose to the air housing. I think I'll install the hose into the air housing using one of those breathers designed for the filter to be in the housing itself.


***"Gettin There"-1973 23' Sequoia- Michael, Onans smell, "Go solar/wind power!"

[Updated on: Sun, 19 December 2010 10:37]

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Re: [GMCnet] pcv/breather [message #108968 is a reply to message #108962] Sun, 19 December 2010 11:09 Go to previous messageGo to next message
Steven Ferguson is currently offline  Steven Ferguson   United States
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Michael,
The OEM setup works best.

On Sun, Dec 19, 2010 at 9:37 AM, Michael <radioactive626@msn.com> wrote:

>
>
> Only cause I need the book "gmc for dummies" I'm still guessing after
> everything that is said I need to switch the pcv valve to the passenger
> side.
> On the drivers side I'm going to take off the valve cover breather and
> install a hose to the air housing. I think I'll install the hose into the
> air housing using one of those breathers designed for the filter to be in
> the housing itself.
> --
> 1973 23' Sequoia-
> Michael, Casa Grande, AZ
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
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>



--
Steve Ferguson
Sierra Vista, AZ
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Re: [GMCnet] pcv/breather [message #108991 is a reply to message #108968] Sun, 19 December 2010 13:09 Go to previous message
gmcrv1 is currently offline  gmcrv1   United States
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Tom Lins sells the "GMC for Dummies" book, but I think it is on digital
media. One of those must have items.

JMHO,

Tom Eckert N2VWN
73 Glacier
Oakland, TN



On Sun, Dec 19, 2010 at 11:09 AM, Steven Ferguson <botiemad11@gmail.com>wrote:

> Michael,
> The OEM setup works best.
>
> On Sun, Dec 19, 2010 at 9:37 AM, Michael <radioactive626@msn.com> wrote:
>
> >
> >
> > Only cause I need the book "gmc for dummies" I'm still guessing after
> > everything that is said I need to switch the pcv valve to the passenger
> > side.
> > On the drivers side I'm going to take off the valve cover breather and
> > install a hose to the air housing. I think I'll install the hose into the
> > air housing using one of those breathers designed for the filter to be in
> > the housing itself.
> > --
> > 1973 23' Sequoia-
> > Michael, Casa Grande, AZ
> > _______________________________________________
> > GMCnet mailing list
> > List Information and Subscription Options:
> > http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
> >
>
>
>
> --
> Steve Ferguson
> Sierra Vista, AZ
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
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