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[GMCnet] Main Caps for a 403 [message #190772] Mon, 19 November 2012 17:50 Go to next message
James Hupy is currently offline  James Hupy   United States
Messages: 6806
Registered: May 2010
Karma: -62
Senior Member
I received a request today by phone for the main caps for a 403 OLDS
engine. A fellow in Pa. called me, he is having a 403 rebuilt by a machine
shop, and they have determined that the ones in the engine are not
rebuildable. Does anybody out there have a 403 that they would be willing
to salvage the main caps and help this fellow out? I do not have any 403
core motors presently. Remember that he is in Pa. If you do, PM me and I
will provide his phone number so that you may talk directly to him.
Jim Hupy
Salem, OR
78 GMC Royale 403
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Re: [GMCnet] Main Caps for a 403 [message #190774 is a reply to message #190772] Mon, 19 November 2012 18:49 Go to previous messageGo to next message
C Boyd is currently offline  C Boyd   United States
Messages: 2629
Registered: April 2006
Karma: 18
Senior Member
Sir: I believe all the small block Olds uses the same crank as they all have the same stroke. The only difference is the bore. The recomended 403 race motor is to use the 330 crank as all before 1968 were steel (but must use the early bolt pattern flexplate) and to use pre 1973 (smog) 350 heads. As for the main caps they should be the same.. In 1977 Olds repordly made 2500 solid main web blocks. Reported to be in vehicles with tow package and some Toros. They did not have the 3 windows in the webs as all the other small blocks except the diesel. The 350 diesel shares the crank dia with the big block and main caps will not work. Small blocks main caps will have 7/16" bolts except #5 cap will have 1/2" bolts.
Hope this helps..





James Hupy wrote on Mon, 19 November 2012 18:50

I received a request today by phone for the main caps for a 403 OLDS
engine. A fellow in Pa. called me, he is having a 403 rebuilt by a machine
shop, and they have determined that the ones in the engine are not
rebuildable. Does anybody out there have a 403 that they would be willing
to salvage the main caps and help this fellow out? I do not have any 403
core motors presently. Remember that he is in Pa. If you do, PM me and I
will provide his phone number so that you may talk directly to him.
Jim Hupy
Salem, OR
78 GMC Royale 403
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C. Boyd
76 Crestmont
East Tennessee
Re: [GMCnet] Main Caps for a 403 [message #190783 is a reply to message #190774] Mon, 19 November 2012 20:26 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
Senior Member
Jim , Have him call Joe Mondello Engines in Tennessee.
They have a new crew after Joe passed away.
931-459-2760


On Mon, Nov 19, 2012 at 4:50 PM, Charles Boyd <covered-wagon@comcast.net>wrote:

>
>
> Sir: I believe all the small block Olds uses the same crank as they all
> have the same stroke. The only difference is the bore. The recomended 403
> race motor is to use the 330 crank as all before 1968 were steel (but must
> use the early bolt pattern flexplate) and to use pre 1973 (smog) 350 heads.
> As for the main caps they should be the same.. In 1977 Olds repordly made
> 2500 solid main web blocks. Reported to be in vehicles with tow package and
> some Toros. They did not have the 3 windows in the webs as all the other
> small blocks except the diesel. The 350 diesel shares the crank dia with
> the big block and main caps will not work. Small blocks main caps will
> have 7/16" bolts except #5 cap will have 1/2" bolts.
> Hope this helps..
>
>
>
>
>
> James Hupy wrote on Mon, 19 November 2012 18:50
> > I received a request today by phone for the main caps for a 403 OLDS
> > engine. A fellow in Pa. called me, he is having a 403 rebuilt by a
> machine
> > shop, and they have determined that the ones in the engine are not
> > rebuildable. Does anybody out there have a 403 that they would be willing
> > to salvage the main caps and help this fellow out? I do not have any 403
> > core motors presently. Remember that he is in Pa. If you do, PM me and I
> > will provide his phone number so that you may talk directly to him.
> > Jim Hupy
> > Salem, OR
> > 78 GMC Royale 403
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
>
> --
> C. Boyd
> 76 Crestmont
> East Tennessee
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>



--
Jim Kanomata
Applied/GMC, Fremont,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] Main Caps for a 403 [message #190838 is a reply to message #190772] Tue, 20 November 2012 09:44 Go to previous messageGo to next message
Ray Erspamer is currently offline  Ray Erspamer   United States
Messages: 1707
Registered: May 2007
Location: Milwaukee Wisconsin
Karma: -3
Senior Member
Always trying to learn here, so I need to ask, what are you referring to when
you say "CAPS" ???

I've looked in the parts manual and don't see anything listed as caps.

Thanks

Ray


Ray & Lisa
78 Royale "Great Lakes Eagle"
Center Kitchen TZE368V101144
Wauwatosa, Wisconsin 53226
Email: 78GMC-Royale@att.net
414-745-3188
Web Site: http://ray-lisa.page.tl/




________________________________
From: James Hupy <jamesh1296@gmail.com>
To: gmclist@temp.gmcnet.org
Sent: Mon, November 19, 2012 5:50:51 PM
Subject: [GMCnet] Main Caps for a 403

I received a request today by phone for the main caps for a 403 OLDS
engine. A fellow in Pa. called me, he is having a 403 rebuilt by a machine
shop, and they have determined that the ones in the engine are not
rebuildable. Does anybody out there have a 403 that they would be willing
to salvage the main caps and help this fellow out? I do not have any 403
core motors presently. Remember that he is in Pa. If you do, PM me and I
will provide his phone number so that you may talk directly to him.
Jim Hupy
Salem, OR
78 GMC Royale 403
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Ray Erspamer 78 GMC Royale Center Kitchen 403, 3.70 Final Drive Holley Sniper Quadrajet EFI System, Holley Hyperspark Ignition System 414-484-9431
Re: [GMCnet] Main Caps for a 403 [message #190841 is a reply to message #190772] Tue, 20 November 2012 09:50 Go to previous messageGo to next message
Craig Lechowicz is currently offline  Craig Lechowicz   United States
Messages: 541
Registered: October 2006
Location: Waterford, MI
Karma: 0
Senior Member
Ray,
The main caps (or main bearing caps) are semi-circular pieces that bolt to the bottom of the engine block to support the crankshaft. The block provides half the circle for the crankshaft, and the caps provide the remaining half.


Craig Lechowicz
'77 Kingsley, Waterford, MI
Re: [GMCnet] Main Caps for a 403 [message #190844 is a reply to message #190838] Tue, 20 November 2012 10:02 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
Messages: 6806
Registered: May 2010
Karma: -62
Senior Member
Ray, The main bearing caps are separate pieces that bolt into place to
contain the crankshaft and main bearings. If the engine is resting on the
intake valley, they would be visible as heavy crude pieces bolted into the
crankshaft webs of the engine.
Jim Hupy
Salem, Or
78 Gmc Royale 403
On Nov 20, 2012 7:45 AM, "Ray Erspamer" <78gmc-royale@att.net> wrote:

> Always trying to learn here, so I need to ask, what are you referring to
> when
> you say "CAPS" ???
>
> I've looked in the parts manual and don't see anything listed as caps.
>
> Thanks
>
> Ray
>
>
> Ray & Lisa
> 78 Royale "Great Lakes Eagle"
> Center Kitchen TZE368V101144
> Wauwatosa, Wisconsin 53226
> Email: 78GMC-Royale@att.net
> 414-745-3188
> Web Site: http://ray-lisa.page.tl/
>
>
>
>
> ________________________________
> From: James Hupy <jamesh1296@gmail.com>
> To: gmclist@temp.gmcnet.org
> Sent: Mon, November 19, 2012 5:50:51 PM
> Subject: [GMCnet] Main Caps for a 403
>
> I received a request today by phone for the main caps for a 403 OLDS
> engine. A fellow in Pa. called me, he is having a 403 rebuilt by a machine
> shop, and they have determined that the ones in the engine are not
> rebuildable. Does anybody out there have a 403 that they would be willing
> to salvage the main caps and help this fellow out? I do not have any 403
> core motors presently. Remember that he is in Pa. If you do, PM me and I
> will provide his phone number so that you may talk directly to him.
> Jim Hupy
> Salem, OR
> 78 GMC Royale 403
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
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Re: [GMCnet] Main Caps for a 403 [message #190845 is a reply to message #190841] Tue, 20 November 2012 10:02 Go to previous messageGo to next message
Ray Erspamer is currently offline  Ray Erspamer   United States
Messages: 1707
Registered: May 2007
Location: Milwaukee Wisconsin
Karma: -3
Senior Member
Thanks Craig, that's what I thought they were.

Another part I don't understand is the "rebuilding". Don't they just get new
bearing halves?

I want to understand as much as I can about this, some time down the road I want
to pickup a used 403 to rebuild and have on hand.



Ray


Ray & Lisa
78 Royale "Great Lakes Eagle"
Center Kitchen TZE368V101144
Wauwatosa, Wisconsin 53226
Email: 78GMC-Royale@att.net
414-745-3188
Web Site: http://ray-lisa.page.tl/




________________________________
From: Craig Lechowicz <craig.lechowicz@sbcglobal.net>
To: gmclist@temp.gmcnet.org
Sent: Tue, November 20, 2012 9:50:29 AM
Subject: Re: [GMCnet] Main Caps for a 403



Ray,
The main caps (or main bearing caps) are semi-circular pieces that bolt to the
bottom of the engine block to support the crankshaft. The block provides half
the circle for the crankshaft, and the caps provide the remaining half.
--
Craig Lechowicz
'77 Kingsley, Waterford, MI
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Ray Erspamer 78 GMC Royale Center Kitchen 403, 3.70 Final Drive Holley Sniper Quadrajet EFI System, Holley Hyperspark Ignition System 414-484-9431
Re: [GMCnet] Main Caps for a 403 [message #190847 is a reply to message #190845] Tue, 20 November 2012 10:09 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
Messages: 6806
Registered: May 2010
Karma: -62
Senior Member
Ray, it is a rare occurance that main caps need to be replaced. I was in
partnership with a fellow in an automotive machine shop, and rebuilt many
engines. I can't recall one instance where I had to replace any of them.
Racing engines are the exception to this.
Jim Hupy
Salem, Or
78 Gmc Royale 403
On Nov 20, 2012 8:02 AM, "Ray Erspamer" <78gmc-royale@att.net> wrote:

> Thanks Craig, that's what I thought they were.
>
> Another part I don't understand is the "rebuilding". Don't they just get
> new
> bearing halves?
>
> I want to understand as much as I can about this, some time down the road
> I want
> to pickup a used 403 to rebuild and have on hand.
>
>
>
> Ray
>
>
> Ray & Lisa
> 78 Royale "Great Lakes Eagle"
> Center Kitchen TZE368V101144
> Wauwatosa, Wisconsin 53226
> Email: 78GMC-Royale@att.net
> 414-745-3188
> Web Site: http://ray-lisa.page.tl/
>
>
>
>
> ________________________________
> From: Craig Lechowicz <craig.lechowicz@sbcglobal.net>
> To: gmclist@temp.gmcnet.org
> Sent: Tue, November 20, 2012 9:50:29 AM
> Subject: Re: [GMCnet] Main Caps for a 403
>
>
>
> Ray,
> The main caps (or main bearing caps) are semi-circular pieces that bolt to
> the
> bottom of the engine block to support the crankshaft. The block provides
> half
> the circle for the crankshaft, and the caps provide the remaining half.
> --
> Craig Lechowicz
> '77 Kingsley, Waterford, MI
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
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Re: [GMCnet] Main Caps for a 403 [message #190849 is a reply to message #190847] Tue, 20 November 2012 10:26 Go to previous messageGo to next message
Ray Erspamer is currently offline  Ray Erspamer   United States
Messages: 1707
Registered: May 2007
Location: Milwaukee Wisconsin
Karma: -3
Senior Member
That's exactly what I thought Jim, thanks for clarifying.

Ray


Ray & Lisa
78 Royale "Great Lakes Eagle"
Center Kitchen TZE368V101144
Wauwatosa, Wisconsin 53226
Email: 78GMC-Royale@att.net
414-745-3188
Web Site: http://ray-lisa.page.tl/




________________________________
From: James Hupy <jamesh1296@gmail.com>
To: gmclist@temp.gmcnet.org
Sent: Tue, November 20, 2012 10:10:01 AM
Subject: Re: [GMCnet] Main Caps for a 403

Ray, it is a rare occurance that main caps need to be replaced. I was in
partnership with a fellow in an automotive machine shop, and rebuilt many
engines. I can't recall one instance where I had to replace any of them.
Racing engines are the exception to this.
Jim Hupy
Salem, Or
78 Gmc Royale 403
On Nov 20, 2012 8:02 AM, "Ray Erspamer" <78gmc-royale@att.net> wrote:

> Thanks Craig, that's what I thought they were.
>
> Another part I don't understand is the "rebuilding". Don't they just get
> new
> bearing halves?
>
> I want to understand as much as I can about this, some time down the road
> I want
> to pickup a used 403 to rebuild and have on hand.
>
>
>
> Ray
>
>
> Ray & Lisa
> 78 Royale "Great Lakes Eagle"
> Center Kitchen TZE368V101144
> Wauwatosa, Wisconsin 53226
> Email: 78GMC-Royale@att.net
> 414-745-3188
> Web Site: http://ray-lisa.page.tl/
>
>
>
>
> ________________________________
> From: Craig Lechowicz <craig.lechowicz@sbcglobal.net>
> To: gmclist@temp.gmcnet.org
> Sent: Tue, November 20, 2012 9:50:29 AM
> Subject: Re: [GMCnet] Main Caps for a 403
>
>
>
> Ray,
> The main caps (or main bearing caps) are semi-circular pieces that bolt to
> the
> bottom of the engine block to support the crankshaft. The block provides
> half
> the circle for the crankshaft, and the caps provide the remaining half.
> --
> Craig Lechowicz
> '77 Kingsley, Waterford, MI
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
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Ray Erspamer 78 GMC Royale Center Kitchen 403, 3.70 Final Drive Holley Sniper Quadrajet EFI System, Holley Hyperspark Ignition System 414-484-9431
Re: [GMCnet] Main Caps for a 403 [message #190850 is a reply to message #190845] Tue, 20 November 2012 10:35 Go to previous messageGo to next message
C Boyd is currently offline  C Boyd   United States
Messages: 2629
Registered: April 2006
Karma: 18
Senior Member
Sir: The main bearing caps are mated to the block when manufactured and line bored. Replacement caps are not available for the Olds as all are theoritacly a few thousanths different. There are aftermarket caps available for some engines to change to 4 bolt main caps by drilling and angling the outside bolts and then line boring. When main journals are damaged the base of the cap and the block mating surface is ground down and re-line bored for oversize bearings. Sometimes this changes the centerline of the crank and a different length timing chain must be used. My theory is if the main caps are not usable the block is trashed. There are machine shops that can do this corectly, depending on damage, but not many in my opinion for the Olds.
If a machine shop is looking for caps for a 403 and don`t know all the small block Olds cranks are the same, I would be looking for a Olds engine shop as Mondello..




Ray Erspamer wrote on Tue, 20 November 2012 11:02

Thanks Craig, that's what I thought they were.

Another part I don't understand is the "rebuilding". Don't they just get new
bearing halves?

I want to understand as much as I can about this, some time down the road I want
to pickup a used 403 to rebuild and have on hand.



Ray


Ray & Lisa
78 Royale "Great Lakes Eagle"
Center Kitchen TZE368V101144
Wauwatosa, Wisconsin 53226
Email: 78GMC-Royale@att.net
414-745-3188
Web Site: http://ray-lisa.page.tl/




________________________________
From: Craig Lechowicz <craig.lechowicz@sbcglobal.net>
To: gmclist@temp.gmcnet.org
Sent: Tue, November 20, 2012 9:50:29 AM
Subject: Re: [GMCnet] Main Caps for a 403



Ray,
The main caps (or main bearing caps) are semi-circular pieces that bolt to the
bottom of the engine block to support the crankshaft. The block provides half
the circle for the crankshaft, and the caps provide the remaining half.
--
Craig Lechowicz
'77 Kingsley, Waterford, MI
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
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C. Boyd
76 Crestmont
East Tennessee
Re: [GMCnet] Main Caps for a 403 [message #190857 is a reply to message #190850] Tue, 20 November 2012 10:48 Go to previous message
James Hupy is currently offline  James Hupy   United States
Messages: 6806
Registered: May 2010
Karma: -62
Senior Member
Guys, please keep in mind the purpose of my original post. I have align
bored many engines using several techniques. This discussion is kinda off
the subject. I was trying to help a fellow gmc'er in Pa. find main caps for
his 403. His name is Earl Geibel, his phone number is seventwofour/6zero2,
onefive thirteen . If anyone out there can help him out. Please give him a
call. Thanks.
Jim Hupy
Salem, Or
78 Gmc Royal
On Nov 20, 2012 8:35 AM, "Charles Boyd" <covered-wagon@comcast.net> wrote:

>
>
> Sir: The main bearing caps are mated to the block when manufactured and
> line bored. Replacement caps are not available for the Olds as all are
> theoritacly a few thousanths different. There are aftermarket caps
> available for some engines to change to 4 bolt main caps by drilling and
> angling the outside bolts and then line boring. When main journals are
> damaged the base of the cap and the block mating surface is ground down and
> re-line bored for oversize bearings. Sometimes this changes the centerline
> of the crank and a different length timing chain must be used. My theory
> is if the main caps are not usable the block is trashed. There are machine
> shops that can do this corectly, depending on damage, but not many in my
> opinion for the Olds.
> If a machine shop is looking for caps for a 403 and don`t know all the
> small block Olds cranks are the same, I would be looking for a Olds engine
> shop as Mondello..
>
>
>
>
> Ray Erspamer wrote on Tue, 20 November 2012 11:02
> > Thanks Craig, that's what I thought they were.
> >
> > Another part I don't understand is the "rebuilding". Don't they just
> get new
> > bearing halves?
> >
> > I want to understand as much as I can about this, some time down the
> road I want
> > to pickup a used 403 to rebuild and have on hand.
> >
> >
> >
> > Ray
> >
> >
> > Ray & Lisa
> > 78 Royale "Great Lakes Eagle"
> > Center Kitchen TZE368V101144
> > Wauwatosa, Wisconsin 53226
> > Email: 78GMC-Royale@att.net
> > 414-745-3188
> > Web Site: http://ray-lisa.page.tl/
> >
> >
> >
> >
> > ________________________________
> > From: Craig Lechowicz <craig.lechowicz@sbcglobal.net>
> > To: gmclist@temp.gmcnet.org
> > Sent: Tue, November 20, 2012 9:50:29 AM
> > Subject: Re: [GMCnet] Main Caps for a 403
> >
> >
> >
> > Ray,
> > The main caps (or main bearing caps) are semi-circular pieces that bolt
> to the
> > bottom of the engine block to support the crankshaft. The block
> provides half
> > the circle for the crankshaft, and the caps provide the remaining half.
> > --
> > Craig Lechowicz
> > '77 Kingsley, Waterford, MI
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
>
> --
> C. Boyd
> 76 Crestmont
> East Tennessee
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
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