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[GMCnet] Don't assume that the carb filter is clean because you have a filter at the rear [message #322519] Tue, 22 August 2017 23:35 Go to next message
BobDunahugh is currently offline  BobDunahugh   United States
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I did. WRONG. Every now, and then I'd look at my clear gas filter that is between the tank, and my rear electric pump. It's always been clean. Two weeks ago I had a terrible time getting home. Pulled the carb filter tonight. That filter was almost clogged. Bob Dunahugh 78 Royale
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Re: [GMCnet] Don't assume that the carb filter is clean because you have a filter at the rear [message #322522 is a reply to message #322519] Wed, 23 August 2017 01:32 Go to previous messageGo to next message
johnd01 is currently offline  johnd01   United States
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How many filters do we need? Do we really need the carb filter if we have
an other?

On Tue, Aug 22, 2017 at 9:35 PM, Bob Dunahugh wrote:

> I did. WRONG. Every now, and then I'd look at my clear gas filter that is
> between the tank, and my rear electric pump. It's always been clean. Two
> weeks ago I had a terrible time getting home. Pulled the carb filter
> tonight. That filter was almost clogged. Bob Dunahugh 78 Royale
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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Johnd01 John Phillips Avion A2600 TZE064V101164 Rancho Cordova, CA (Sacramento)
Re: [GMCnet] Don't assume that the carb filter is clean because you have a filter at the rear [message #322524 is a reply to message #322522] Wed, 23 August 2017 06:36 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
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Location: Sydney, Australia
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G'day,

After dropping & cleaning the tanks Ken Frey put a filter (belt) in my carbureted GMC here:

http://www.gmcmhphotos.com/photos/aa-miscellaneous-photos/p54750-fuel-pump-inlet-filter.html

It keeps crud out of the carb filter (suspenders). :-)

Regards,
Rob M.
The Pedantic Mechanic
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
USA '77 Kingsley - TZE 267V100808

-----Original Message-----
From: Gmclist [mailto:gmclist-bounces@list.gmcnet.org] On Behalf Of John Phillips
Sent: Wednesday, August 23, 2017 4:32 PM
To: gmclist@list.gmcnet.org
Subject: Re: [GMCnet] Don't assume that the carb filter is clean because you have a filter at the rear

How many filters do we need? Do we really need the carb filter if we have
an other?

*John Phillips*
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Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Re: [GMCnet] Don't assume that the carb filter is clean because you have a filter at the rear [message #322529 is a reply to message #322524] Wed, 23 August 2017 08:37 Go to previous messageGo to next message
Justin Brady is currently offline  Justin Brady   United States
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Karma: 11
Senior Member
Sounds like you need a better prefilter.
The only way that could happen is the first filter is not filtering down to the same level as the carb filter.


Justin Brady http://www.thegmcrv.com/ 1976 Palm Beach 455
Re: [GMCnet] Don't assume that the carb filter is clean because you have a filter at the rear [message #322532 is a reply to message #322529] Wed, 23 August 2017 08:56 Go to previous messageGo to next message
kstockwell is currently offline  kstockwell   United States
Messages: 367
Registered: May 2016
Location: Putney VT
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Senior Member
i just changed my carb filter. What would I look for to see if it was dirty? I had no symptoms, it was preventative

kelly


1978 Kingsley Putney VT
Re: [GMCnet] Don't assume that the carb filter is clean because you have a filter at the rear [message #322535 is a reply to message #322519] Wed, 23 August 2017 09:05 Go to previous messageGo to next message
77Royale   United States
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Registered: June 2014
Location: Mid Michigan
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Senior Member
Cut it open with a razor blade and fan out the paper element, See if there is any crud in it.

77 Royale, Rear Dry Bath. 403, 3.55 Final Drive, Lenzi goodies, Patterson carb and dizzy. Mid Michigan
Re: [GMCnet] Don't assume that the carb filter is clean because you have a filter at the rear [message #322536 is a reply to message #322519] Wed, 23 August 2017 09:14 Go to previous messageGo to next message
Richard Denney is currently offline  Richard Denney   United States
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Registered: April 2010
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Senior Member
Bob, had you replaced the filter when you first installed the external
filter? Seems obvious, but it's a mistake I have made.

I removed the carb filter altogether, and replaced it with an AN-6 adapter.
I then run aircraft hose from there to a compressing AN-6 fitting on the
steel line down at the front crossmember. (I bypassed the mechanical pump,
which is now just a block-off plate, and run an electric pump in the rear
by the tank.) In that aircraft hose, I installed an AN-6 sintered-bronze
filter as a failsafe. I didn't want to see the effects of a degrading hose
between the inline filter back by the tank and the carb in the interior of
the carb, so I have that last-ditch filter. The sintered-bronze filter is
not, I don't think, finer than the paper filter in the back, but it will
catch the stuff I'm protecting against. I have not checked it since I
installed it.

Rick "wrapped in foil-covered insulation" Denney

On Wed, Aug 23, 2017 at 12:35 AM, Bob Dunahugh wrote:

> I did. WRONG. Every now, and then I'd look at my clear gas filter that is
> between the tank, and my rear electric pump. It's always been clean. Two
> weeks ago I had a terrible time getting home. Pulled the carb filter
> tonight. That filter was almost clogged. Bob Dunahugh 78 Royale
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>



--
'73 X-Glacier 230 "Jaws"
Northern Virginia
Offlist email: rick at rickdenney dot com
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Re: [GMCnet] Don't assume that the carb filter is clean because you have a filter at the rear [message #322541 is a reply to message #322535] Wed, 23 August 2017 11:24 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
Never run w/o the small filter at the carb.
That is the final protection to keep crud out of the carb.
I have run lot of Quadra Jet carbs w/o them and suffered the consequence.
Having an aux. filter by the pump is a good concept as it not only filters,
but it will not contribute to vapor lock.

On Wed, Aug 23, 2017 at 7:05 AM, Wayne Rogewski wrote:

> Cut it open with a razor blade and fan out the paper element, See if
> there is any crud in it.
> --
> 77 Royale, Rear Dry Bath. 403, 3.55 Final Drive, Lenzi goodies, Patterson
> carb and dizzy.
> Mid Michigan
>
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Jim Kanomata
Applied/GMC, Newark,CA
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http://www.appliedgmc.com
1-800-752-7502
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Jim Kanomata
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www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] Don't assume that the carb filter is clean because you have a filter at the rear [message #322542 is a reply to message #322519] Wed, 23 August 2017 11:39 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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Registered: January 2004
Location: Hebron, Indiana
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KEEP BOTH filters installed. I one time drove a coach from California to Ohio. It had some rust in the tanks. The inline Wix filter filled up and had to be replaced every second day. At the same time the carb filter clogged had also had to be replaced every second day. They always clogged on opposite days. I went through 6 filters filters on the trip changing one or the other every day.

Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] Don't assume that the carb filter is clean because you have a filter at the rear [message #322550 is a reply to message #322519] Wed, 23 August 2017 12:57 Go to previous messageGo to next message
BobDunahugh is currently offline  BobDunahugh   United States
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Registered: October 2010
Location: Cedar Rapids, IA
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Senior Member
I took the tanks, rear filter/electric pump, and carb with existing filter off the burned GMC. Didn't check the carb filter. As the rear clear filter was clean inside. Then installer all these items on this next 78 Royale. I pulled the carb filter out. And I could hardly blow threw it. Then cut it open. The filter just had a dark tint on it. Bob Dunahugh


________________________________
From: Bob Dunahugh
Sent: Tuesday, August 22, 2017 11:35 PM
To: gmclist@list.gmcnet.org
Subject: Don't assume that the carb filter is clean because you have a filter at the rear


I did. WRONG. Every now, and then I'd look at my clear gas filter that is between the tank, and my rear electric pump. It's always been clean. Two weeks ago I had a terrible time getting home. Pulled the carb filter tonight. That filter was almost clogged. Bob Dunahugh 78 Royale
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Re: [GMCnet] Don't assume that the carb filter is clean because you have a filter at the rear [message #322551 is a reply to message #322535] Wed, 23 August 2017 13:06 Go to previous messageGo to next message
kstockwell is currently offline  kstockwell   United States
Messages: 367
Registered: May 2016
Location: Putney VT
Karma: 4
Senior Member
I hope i didn't throw it away yet...
Not sure why I didn't think of that. I did bring it to the autoparts store to make sure I got the right one. And then I ordered the nylon washers online since no one around here stocks them. I put the warped one back in, no leaks- fingers crossed.

the new ones arrive today so I'll have them with me in case I need them

-k



77Royale wrote on Wed, 23 August 2017 10:05
Cut it open with a razor blade and fan out the paper element, See if there is any crud in it.



1978 Kingsley Putney VT
Re: [GMCnet] Don't assume that the carb filter is clean because you have a filter at the rear [message #322552 is a reply to message #322550] Wed, 23 August 2017 13:10 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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Senior Member
Just a small matter of microns. The carb inlet filter will stop particles
as small as 5 microns. That pretty much includes everything including muddy
water. The upstream in-line filters for the most part are 20 micron. So
some of the really small stuff will pass through them. If you remove the
inlet filter, those small particles will eventually will coat stuff like
floats and inlet needles, and metering rods, and that piston that works in
conjunction with the secondary flap, delaying it from opening. GM would not
have put a filter there if it was not needed.
Jim Hupy
Salem, Or
78 GMC ROYALE 403

On Aug 23, 2017 10:58 AM, "Bob Dunahugh" wrote:

> I took the tanks, rear filter/electric pump, and carb with existing filter
> off the burned GMC. Didn't check the carb filter. As the rear clear filter
> was clean inside. Then installer all these items on this next 78 Royale. I
> pulled the carb filter out. And I could hardly blow threw it. Then cut it
> open. The filter just had a dark tint on it. Bob Dunahugh
>
>
> ________________________________
> From: Bob Dunahugh
> Sent: Tuesday, August 22, 2017 11:35 PM
> To: gmclist@list.gmcnet.org
> Subject: Don't assume that the carb filter is clean because you have a
> filter at the rear
>
>
> I did. WRONG. Every now, and then I'd look at my clear gas filter that is
> between the tank, and my rear electric pump. It's always been clean. Two
> weeks ago I had a terrible time getting home. Pulled the carb filter
> tonight. That filter was almost clogged. Bob Dunahugh 78 Royale
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
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Re: [GMCnet] Don't assume that the carb filter is clean because you have a filter at the rear [message #322554 is a reply to message #322542] Wed, 23 August 2017 13:41 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Registered: July 2006
Location: Belmont, CA
Karma: 9
Senior Member
This method of changing filters frequently is less cost than dropping the
tank and having it cleaned.
Several of our customers have elected to go that way and after few tankful,
the fuel tank cleared up.

On Wed, Aug 23, 2017 at 9:39 AM, Ken Burton wrote:

> KEEP BOTH filters installed. I one time drove a coach from California to
> Ohio. It had some rust in the tanks. The inline Wix filter filled up and
> had to be replaced every second day. At the same time the carb filter
> clogged had also had to be replaced every second day. They always clogged
> on
> opposite days. I went through 6 filters filters on the trip changing one
> or the other every day.
> --
> Ken Burton - N9KB
> 76 Palm Beach
> Hebron, Indiana
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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>



--
Jim Kanomata
Applied/GMC, Newark,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] Don't assume that the carb filter is clean because you have a filter at the rear [message #322572 is a reply to message #322554] Wed, 23 August 2017 17:55 Go to previous messageGo to next message
kstockwell is currently offline  kstockwell   United States
Messages: 367
Registered: May 2016
Location: Putney VT
Karma: 4
Senior Member
it looks like my carb filter is leaking, so I'll pull it and put in a new washer.
I did toss the old one so I don't know if it's dirty. Next time I'll check

-k


1978 Kingsley Putney VT
Re: [GMCnet] Don't assume that the carb filter is clean because you have a filter at the rear [message #322574 is a reply to message #322572] Wed, 23 August 2017 18:04 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Kelly,
That carb filter works opposite of most, so you need to cut it open to see
the buildup of particulets in the filter.
That is one item I carry in my coach, as it is small and does not take up
space and light.

On Wed, Aug 23, 2017 at 3:55 PM, kelly stockwell wrote:

> it looks like my carb filter is leaking, so I'll pull it and put in a new
> washer.
> I did toss the old one so I don't know if it's dirty. Next time I'll check
>
> -k
> --
> 1978 Kingsley
> Putney VT
>
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--
Jim Kanomata
Applied/GMC, Newark,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] Don't assume that the carb filter is clean because you have a filter at the rear [message #322582 is a reply to message #322574] Wed, 23 August 2017 21:06 Go to previous messageGo to next message
kstockwell is currently offline  kstockwell   United States
Messages: 367
Registered: May 2016
Location: Putney VT
Karma: 4
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I bought two!

jimk wrote on Wed, 23 August 2017 19:04
Kelly,
That carb filter works opposite of most, so you need to cut it open to see
the buildup of particulets in the filter.
That is one item I carry in my coach, as it is small and does not take up
space and light.

On Wed, Aug 23, 2017 at 3:55 PM, kelly stockwell wrote:

> it looks like my carb filter is leaking, so I'll pull it and put in a new
> washer.
> I did toss the old one so I don't know if it's dirty. Next time I'll check
>
> -k
> --
> 1978 Kingsley
> Putney VT
>
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Jim Kanomata
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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1978 Kingsley Putney VT
Re: [GMCnet] Don't assume that the carb filter is clean because you have a filter at the rear [message #322587 is a reply to message #322550] Wed, 23 August 2017 23:34 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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Jim I did 3 complete filter changes in 6 day and on each change I progressively more miles be for it clogged again. So yes it as getting better. It was not my coach and I do not think that the owner pulled the tanks after I delivered it. I think he did just what you suggested. Keep changing filters until it cleared up. That big Wix filter that you sell installed just before the fuel pump was a life saver on that trip. It caught most of the stuff and the carb filter caught what smaller stuff got through. I was fighting rust and not gooey crap in the tank.

Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] Don't assume that the carb filter is clean because you have a filter at the rear [message #322588 is a reply to message #322587] Thu, 24 August 2017 00:10 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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The only large Hi Capacity filter to use is the WIX 33161.Other brands have
very little media, that it plugs up right away. I seldom endorse WiX, but
for this application, other brands are only half the media so the dirt
holding capacity is poor.

On Wed, Aug 23, 2017 at 9:34 PM, Ken Burton wrote:

> Jim I did 3 complete filter changes in 6 day and on each change I
> progressively more miles be for it clogged again. So yes it as getting
> better. It
> was not my coach and I do not think that the owner pulled the tanks after
> I delivered it. I think he did just what you suggested. Keep changing
> filters until it cleared up. That big Wix filter that you sell installed
> just before the fuel pump was a life saver on that trip. It caught most of
> the stuff and the carb filter caught what smaller stuff got through. I
> was fighting rust and not gooey crap in the tank.
> --
> Ken Burton - N9KB
> 76 Palm Beach
> Hebron, Indiana
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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>



--
Jim Kanomata
Applied/GMC, Newark,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] Don't assume that the carb filter is clean because you have a filter at the rear [message #322590 is a reply to message #322588] Thu, 24 August 2017 01:09 Go to previous message
Guy Lopes is currently offline  Guy Lopes   United States
Messages: 499
Registered: April 2004
Location: Sacramento, CA
Karma: 3
Senior Member
Jim, I always try to listen closely to people who know much more about a
subject than I do. Considering you're the filter engineer, I have now placed
this filter on my "to buy" list. Thanks!

Guy "I love Rick Denny's quotes within his name" Lopes
1976 ish RB Birchaven
Sacramento, CA



-----Original Message-----
From: Gmclist [mailto:gmclist-bounces@list.gmcnet.org] On Behalf Of Jim
Kanomata
Subject: Re: [GMCnet] Don't assume that the carb filter is clean because you
have a filter at the rear

The only large Hi Capacity filter to use is the WIX 33161.Other brands have
very little media, that it plugs up right away. I seldom endorse WiX, but
for this application, other brands are only half the media so the dirt
holding capacity is poor.




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Guy Lopes 76 Birchaven "Orion" Sacramento, CA W6TOL www.GMC-Guy.com
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