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Part #. for carb filter? and, do i need it? [message #361048] Mon, 21 December 2020 06:32 Go to next message
hertfordnc is currently offline  hertfordnc   United States
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Coach sat for a few years. I've drained the tanks but a new fuel filter clogged after 30 miles or so.

It has cartridge filter system up front instead of the inline. Makes it very easy to change filters.

Can i remove the carb filter until i get this worked out?

I'm gonna' need a few, what is the part number? - 74 Birch with 455



Dave & Ellen Silva Hertford, NC 76 Birchaven, 1-ton and other stuff Currently planning the Great american Road Trip Summer 2021 It's gonna take a lot of Adderall to get this thing right.

[Updated on: Mon, 21 December 2020 06:33]

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Re: Part #. for carb filter? and, do i need it? [message #361049 is a reply to message #361048] Mon, 21 December 2020 06:45 Go to previous messageGo to next message
C Boyd is currently offline  C Boyd   United States
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Sir, my recommendation is to leave the filter in the carb. I believe it is a finer filter than the inline versions and will trap stuff that will clog up carb passages. I also believe it buffers the pulse of the fuel pump for a more even flow thru the float needle. Always use a 1” back up wrench to hold the housing as it is easy to cross thread and strip the threads and a 5/8 line wrench to keep from rounding off the fuel line.





hertfordnc wrote on Mon, 21 December 2020 07:32
Coach sat for a few years. I've drained the tanks but a new fuel filter clogged after 30 miles or so.

It has cartridge filter system up front instead of the inline. Makes it very easy to change filters.

Can i remove the carb filter until i get this worked out?

I'm gonna' need a few, what is the part number? - 74 Birch with 455



C. Boyd
76 Crestmont
East Tennessee
Re: Part #. for carb filter? and, do i need it? [message #361051 is a reply to message #361049] Mon, 21 December 2020 07:44 Go to previous messageGo to next message
Carl S. is currently offline  Carl S.   United States
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The filter in the Q-jet is a Wix 33048. I agree with Chuck, above. Keep one in there, at least until you have the tank problem worked out. It is a finer filter and is your last line of defense against fine particles in your carburetor. Maybe after you start getting a clean element in your cartridge filter, you might be able to do away with the carb filter, but it's probably still a good idea to continue running it.

Be VERY careful threading the housing into the carburetor. It is easy to strip and/or stretch the threads in the carb. You can also get the little nylon gasket for the filter housing at better auto parts stores. Look for a guy with some gray in his beard at a NAPA or similar store. The young guys at O'Reilly's generally will not have a clue about carb parts.


Carl Stouffer '75 ex Palm Beach Tucson, AZ. Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
Re: [GMCnet] Part #. for carb filter? and, do i need it? [message #361057 is a reply to message #361051] Mon, 21 December 2020 10:01 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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I'm all for keeping that filter as it is the final to protect the
carburetor.
I have run the same type of carburetors on our cars and trucks when we had
the carburetors.
Yes, I have ran it without and paid the price.later.
Just because you ran it without it without problem , don't think it works
that way most of the time.
Particulates come off your rubber hose and rusting steel line and rubber
diaphragm fuel pump.
Factory people are no idiots and know more than us .

On Mon, Dec 21, 2020 at 5:45 AM Carl Stouffer via Gmclist <
gmclist@list.gmcnet.org> wrote:

> The filter in the Q-jet is a Wix 33048. I agree with Chuck, above. Keep
> one in there, at least until you have the tank problem worked out. It is a
> finer filter and is your last line of defense against fine particles in
> your carburetor. Maybe after you start getting a clean element in your
> cartridge filter, you might be able to do away with the carb filter, but
> it's probably still a good idea to continue running it.
>
> Be VERY careful threading the housing into the carburetor. It is easy to
> strip and/or stretch the threads in the carb. You can also get the little
> nylon gasket for the filter housing at better auto parts stores. Look for
> a guy with some gray in his beard at a NAPA or similar store. The young
> guys at O'Reilly's generally will not have a clue about carb parts.
> --
> Carl Stouffer
> '75 ex Palm Beach
> Tucson, AZ.
> Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive,
> Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American
> Eagles,
> Solar battery charging. GMCSJ and GMCMI member
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>


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Jim Kanomata
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.gmcrvparts.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] Part #. for carb filter? and, do i need it? [message #361058 is a reply to message #361057] Mon, 21 December 2020 10:33 Go to previous messageGo to next message
hertfordnc is currently offline  hertfordnc   United States
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THanks. i ordered a couple carb filters and several regular fuel filters. I believe the tanks were refreshed during the rahab and it sat with full tanks all this time so i am hoping to clear the debris without having to do anything heroic.


Dave & Ellen Silva Hertford, NC 76 Birchaven, 1-ton and other stuff Currently planning the Great american Road Trip Summer 2021 It's gonna take a lot of Adderall to get this thing right.
Re: [GMCnet] Part #. for carb filter? and, do i need it? [message #361059 is a reply to message #361058] Mon, 21 December 2020 12:19 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   Canada
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Dave,

Please take to heart the cautions about the thread in the carburetor body. This is easily damaged and I have witness this more than a few times.

When I change that filter (I carry them in spares), first I put a wrench on the 1" at the carburetor filter carrier and loosen the fuel line. The metal fuel line will not want to come clear away on a stock 455. You can run the line nut back.
Then, I loosen the 1" filter carrier.
Then, I remove the four screws that hold the carburetor to the manifold. Mine has enough slack in the rubber vacuum lines to move the carburetor so the metal fuel line can be clear.
Then, I back out the filter carrier and change the filter. Be sure to note that the open end of the filter goes into the carrier. There may or may not be a spring and a special washer at the other end of the filter. This seems to be model and year dependent.
Now, screw the filter carrier back in with fingers only. If it does not spin down to the seat with figures only, try again.
*** This is a very fine thread and it is easily crossed and damaged. When it is, the carburetor body is junk. ***
With the filter carrier home, slide the carburetor back to where you can start the metal line back on its fitting.
Put the four screws back in the carburetor and snug them down. If they get reefed on, the can distort the carburetor body. This is not desirable.
Now you get to snug up the filter carrier and then the metal fuel line.

*** At one time there was a repair part for the carburetor filter carrier thread, but I have not seen one in decades and am not sure that they are still even available. ***

This can't be all that hard, I have done it a bunch even before I had the coach.

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
Re: [GMCnet] Part #. for carb filter? and, do i need it? [message #361060 is a reply to message #361059] Mon, 21 December 2020 13:00 Go to previous messageGo to next message
hertfordnc is currently offline  hertfordnc   United States
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Matt Colie wrote on Mon, 21 December 2020 12:19
Dave,

Please take to heart the cautions about the thread in the carburetor body. This is easily damaged and I have witness this more than a few times.

Thanks Matt. We really should compile these little instructions of yours.

Meanwhile, what is your gut call on the tanks?

Here's the story; when the coach was rehabbed in 2013 the tanks were probably removed and cleaned. At the very least, the bottoms were painted.

When i got the coach it had a lot of gas in the tank. I removed about 12 gallons but i was only able to add about 20.


In all likelihood it sat for those seven years mostly full.

Hopefully not too much rust formed.

What else can I do short dropping the tanks ?






Dave & Ellen Silva Hertford, NC 76 Birchaven, 1-ton and other stuff Currently planning the Great american Road Trip Summer 2021 It's gonna take a lot of Adderall to get this thing right.
Re: Part #. for carb filter? and, do i need it? [message #361061 is a reply to message #361048] Mon, 21 December 2020 13:37 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
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If I had the plans to cross country with the coach as
You do. And i had any fuel delivery questions. Drop the tanks and either replace all or check/verify all.

If you have the wood ramps. It really is a weekend job to replace all fuel lines.

You can see inside tanks and make a decision on those easily.

Fuel delivery problems are way too common. And very annoying as the coach seems to run fine until it doesnt’t.

would start by setting up an electric fuel pump to run through a fuel filter system and back
To the gas tank.

Cycle the gas through through a filter and can check flow.

A fuel pressure gauge is also nice to have.



Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
Re: [GMCnet] Part #. for carb filter? and, do i need it? [message #361062 is a reply to message #361061] Mon, 21 December 2020 13:49 Go to previous messageGo to next message
Mike Kelley is currently offline  Mike Kelley   United States
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Jon R:
You Sir are so practical and free w/ good advice - keep up the good work for all our GMC’ers!
Mike/the Corvair a holic

Sent from my iPhone

> On Dec 21, 2020, at 1:37 PM, Jon Roche via Gmclist wrote:
>
> If I had the plans to cross country with the coach as
> You do. And i had any fuel delivery questions. Drop the tanks and either replace all or check/verify all.
>
> If you have the wood ramps. It really is a weekend job to replace all fuel lines.
>
> You can see inside tanks and make a decision on those easily.
>
> Fuel delivery problems are way too common. And very annoying as the coach seems to run fine until it doesnt’t.
>
> would start by setting up an electric fuel pump to run through a fuel filter system and back
> To the gas tank.
>
> Cycle the gas through through a filter and can check flow.
>
> A fuel pressure gauge is also nice to have.
>
>
> --
> Jon Roche
> 75 palm beach
> EBL EFI, manny headers, Micro Level, rebuilt most of coach now.
> St. Cloud, MN
> http://lqqkatjon.blogspot.com/
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

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Re: Part #. for carb filter? and, do i need it? [message #361068 is a reply to message #361048] Mon, 21 December 2020 16:25 Go to previous messageGo to next message
Greg C. is currently offline  Greg C.   United States
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I wholeheartedly agree with Matt about how to go about changing the filter.

I brought my new coach 1000 miles back from Texas in July. It had water in the fuel, and several folks suggested changing the carb filter. I bought one, but then the coach decided it would run mostly fine with enough Heet in it that I did not try to change it. When I got home, I polished (diesel boat term) the fuel by draining it all and pumping it through a filter/water separator with an external electric pump. So then it was time to change that filter. It had been stripped and JB Welded in. If I had tried to change it on the road, I'd have been screwed as it just fell out in pieces when I put a wrench to it.

Chuck Boyd had a 78 parts coach and sold me another carb.

At least three companies I have found will drill and helicoil a stripped out carb body so it can be salvaged.

I bought one of the thread repair fittings Matt spoke of. Basically, it is just a standard filter housing with four slots milled in the threads so it will recut the stripped threads in the body. In my case,

there were not enough threads remaining for it to work, so I plan on shipping it off and having it helicoiled by someone who has the tools and expertise to do it right.

Take five minutes and pull the carb off the intake as suggested so that you can reinsert the filter assembly by hand and you won't strip the threads.


Greg Crawford KM4ZCR Knoxville, TN "Ruby Sue" 1977 Royale Rear Bath 403 Engine American Eagle Wheels Early Version Alex Sirum Quad bags
Re: [GMCnet] Part #. for carb filter? and, do i need it? [message #361073 is a reply to message #361068] Tue, 22 December 2020 06:28 Go to previous messageGo to next message
Bruce Hart is currently offline  Bruce Hart   United States
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Senior Member
When checking the inside of the tanks besure to use a mirror and check the
inside top of the tank. That is where my rust was at as the bottom of the
tank looked clean. Jim Huppy was the guy that pointed it out to me.

On Mon, Dec 21, 2020 at 3:26 PM Greg Crawford via Gmclist <
gmclist@list.gmcnet.org> wrote:

> I wholeheartedly agree with Matt about how to go about changing the filter.
>
> I brought my new coach 1000 miles back from Texas in July. It had water
> in the fuel, and several folks suggested changing the carb filter. I bought
> one, but then the coach decided it would run mostly fine with enough Heet
> in it that I did not try to change it. When I got home, I polished (diesel
> boat term) the fuel by draining it all and pumping it through a
> filter/water separator with an external electric pump. So then it was time
> to change
> that filter. It had been stripped and JB Welded in. If I had tried to
> change it on the road, I'd have been screwed as it just fell out in pieces
> when
> I put a wrench to it.
>
> Chuck Boyd had a 78 parts coach and sold me another carb.
>
> At least three companies I have found will drill and helicoil a stripped
> out carb body so it can be salvaged.
>
> I bought one of the thread repair fittings Matt spoke of. Basically, it is
> just a standard filter housing with four slots milled in the threads so it
> will recut the stripped threads in the body. In my case,
>
> there were not enough threads remaining for it to work, so I plan on
> shipping it off and having it helicoiled by someone who has the tools and
> expertise to do it right.
>
> Take five minutes and pull the carb off the intake as suggested so that
> you can reinsert the filter assembly by hand and you won't strip the
> threads.
> --
> Greg Crawford
> KM4ZCR
> Knoxville, TN
>
> "Ruby Sue"
> 1977 Royale
> Rear Bath
> 403 Engine
> American Eagle Wheels
> Early Version Alex Sirum Quad bags
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>


--
Bruce Hart
1976 Palm Beach
Milliken, Co
GMC=Got More Class
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Bruce Hart 1976 Palm Beach 1977 28' Kingsley La Grange, Wyoming
Re: Part #. for carb filter? and, do i need it? [message #361085 is a reply to message #361061] Wed, 23 December 2020 08:12 Go to previous messageGo to next message
hertfordnc is currently offline  hertfordnc   United States
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lqqkatjon wrote on Mon, 21 December 2020 13:37
If I had the plans to cross country with the coach as
You do. And i had any fuel delivery questions. Drop the tanks and either replace all or check/verify all.




Yeah, i'll probably end up doing that. Hope to get in on a lift in a couple weeks to swap the trans, at which time i will have someone more knowledgeable look at everything and tell me what to do.

Then the plan is to daily drive it (better MPG than my Excursion) and put a few thousand miles on it over the next few months. That should shake the cobwebs out pretty well.

And of course, if this dirty fuel problem does not go away I'll drop the tanks. But my hunch is if the tanks and fuel lines were refreshed in 2013 and it was left full, that may not be necessary.



Dave & Ellen Silva Hertford, NC 76 Birchaven, 1-ton and other stuff Currently planning the Great american Road Trip Summer 2021 It's gonna take a lot of Adderall to get this thing right.
Re: [GMCnet] Part #. for carb filter? and, do i need it? [message #361088 is a reply to message #361085] Wed, 23 December 2020 08:40 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Just make sure your head is on the other side and not over it.\One can also
insulate for noise.
I prefer the Onan as most of repair shops that work on the GMC coach are
familiar with the Onan.

On Wed, Dec 23, 2020 at 6:13 AM dave silva via Gmclist <
gmclist@list.gmcnet.org> wrote:

> lqqkatjon wrote on Mon, 21 December 2020 13:37
>> If I had the plans to cross country with the coach as
>> You do. And i had any fuel delivery questions. Drop the tanks and
> either replace all or check/verify all.
>
>
> Yeah, i'll probably end up doing that. Hope to get in on a lift in a
> couple weeks to swap the trans, at which time i will have someone more
> knowledgeable look at everything and tell me what to do.
>
> Then the plan is to daily drive it (better MPG than my Excursion) and put
> a few thousand miles on it over the next few months. That should shake the
> cobwebs out pretty well.
>
> And of course, if this dirty fuel problem does not go away I'll drop the
> tanks. But my hunch is if the tanks and fuel lines were refreshed in 2013
> and it was left full, that may not be necessary.
>
>
> --
> Dave & Ellen Silva
> Hertford, NC
>
> 74 Birchaven, 1-ton and other stuff
>
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>


--
Jim Kanomata
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.gmcrvparts.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: Part #. for carb filter? and, do i need it? [message #361089 is a reply to message #361085] Wed, 23 December 2020 09:04 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
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Daily driving it is the best line of thought. I make a point
Of
Doing that as often as
I can. That for sure tells you what is working or not.


Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
Re: Part #. for carb filter? and, do i need it? [message #361099 is a reply to message #361048] Thu, 24 December 2020 09:28 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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To Matt’s detailed filter instructions I add one more “trick”. A drop of light oil at the flair to fuel line fiction point. This helps prevent the fuel line from “ winding up” when snugging the flair nut and acting like a torsion bar. Otherwise if wound up it wants to loosen with hot/cold/vibration cycles and give mysterious fuel odor. The single drops will quickly disappear with no visual leak cues. Also makes next service easier.

John Lebetski
Woodstock, IL
77 Eleganza II
Re: [GMCnet] Part #. for carb filter? and, do i need it? [message #361104 is a reply to message #361099] Thu, 24 December 2020 13:16 Go to previous message
jimk is currently offline  jimk   United States
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John,
There are lotof great tricks, Never heard or used it.
Thank you for sharing that with us.
Also on brake lines.

On Thu, Dec 24, 2020 at 7:29 AM John R. Lebetski via Gmclist <
gmclist@list.gmcnet.org> wrote:

> To Matt’s detailed filter instructions I add one more “trick”. A drop of
> light oil at the flair to fuel line fiction point. This helps prevent
> the fuel line from “ winding up” when snugging the flair nut and acting
> like a torsion bar. Otherwise if wound up it wants to loosen with
> hot/cold/vibration cycles and give mysterious fuel odor. The single drops
> will quickly disappear with no visual leak cues. Also makes next service
> easier.
> --
> John Lebetski
> Woodstock, IL
> 77 Eleganza II
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>


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