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[GMCnet] Gas Tank Sender repair [message #108273] Sat, 11 December 2010 23:32 Go to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
Messages: 7117
Registered: August 2005
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Senior Member
This was my problem:
both gas tank senders did not work on my new (old ) 73-23.

When I installed the Howell TBI, I found the tanks had been reworked by the
PO.
Every thing looked good
but
Neither of the senders worked, so I had to check the wiring -- it was ok to
the selector .
Now I had to check the wiring at the senders ----
I could not convince myself to drop the tanks for this, So I went in from
the top (GMC tool ;>)
the wiring was good, the sender was bad.
Now I had to enlarge the hole so I could remove the sender from the top.
this is how it was done
http://www.gmcmhphotos.com/photos/showphoto.php?photo=37203&title=slide132&cat=5677

http://goo.gl/92G2G

I soldered the connection, but I might change it and put in a bolt later
(you can do that with a cap on the hole in the floor ;>)

Future fuel system upgrades without dropping the tanks:

• Single pickup / sender (no need for 2)
• remove tank selector solenoid
• connect both tanks at drain hole for a single tank. (Jim Bound’s mod)
• Remove tank selector switch on the dash
• Add an in-tank pump (Emery’s mod)
• No more “Mystery Reserve “
• Simplify and improve fuel system (no more vapor lock)
• No more removing the tanks for improvements.

JWID
gene


--
Gene Fisher -- 74-23,77PB/ore/ca
“Give a man a fish; you have fed him for today --- give him a URL and
-------
http://gmcmotorhome.info/
Alternator Protection Cable
http://gmcmotorhome.info/APC.html



--
Gene Fisher -- 74-23,77PB/ore/ca
“Give a man a fish; you have fed him for today --- give him a URL and
-------
http://gmcmotorhome.info/
Alternator Protection Cable
http://gmcmotorhome.info/APC.html
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Re: [GMCnet] Gas Tank Sender repair [message #108309 is a reply to message #108273] Sun, 12 December 2010 09:59 Go to previous messageGo to next message
midlf is currently offline  midlf   United States
Messages: 2212
Registered: July 2007
Location: SE Wisc. (Palmyra)
Karma: 1
Senior Member
Mr ERFisher wrote on Sat, 11 December 2010 23:32

<snip>

the wiring was good, the sender was bad.

I soldered the connection, but I might change it and put in a bolt later


JWID
gene





I have 4 senders. All had some form of dysfunction for sorta worked to didn't work at all. All were bad at the connection thru the cover plate. Also if the floats appear stuck when dry don't jump to conclusions. The two I have cleaned up so far don't move on their own when dry but move quite well when wet with kero, wd-40 or gasoline.

Gene avoids dropping the tanks. SteveS does not think it is that big of a deal. However I will be setting up my 74 so I can access the senders and in-tank fuel pumps (for carburetor) without dropping the tanks.


Steve Southworth
1974 Glacier TZE064V100150 (for workin on)
1975 Transmode TZE365V100394 (parts & spares)
Palmyra WI
Re: [GMCnet] Gas Tank Sender repair [message #108316 is a reply to message #108309] Sun, 12 December 2010 10:50 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
Messages: 7117
Registered: August 2005
Karma: 2
Senior Member
>
> Gene avoids dropping the tanks. SteveS does not think it is that big of a
> deal. However I will be setting up my 74 so I can access the senders and
> in-tank fuel pumps (for carburetor) without dropping the tanks.
>
> The point is:
1- everyone I know who has dropped their tanks, have done it twice
2-The trauma to the GMC is extensive - 10 or more hose and wiring
connections shown here:

http://www.gmcmhphotos.com/photos/showphoto.php?photo=19216&cat=4634

have to be broken and replaced.

3-every GMC owner will have to work on these tanks, because of bad hoses,
bad senders, worry about rust in tanks (mine were fine by the way), vapor
lock issues,
4-every GMC will have to have it done more than once

so, I am not advocating every one do this, it is:

JWID
GENE


--
Gene Fisher -- 74-23,77PB/ore/ca
“Give a man a fish; you have fed him for today --- give him a URL and
-------
http://gmcmotorhome.info/
Alternator Protection Cable
http://gmcmotorhome.info/APC.html
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Re: [GMCnet] Gas Tank Sender repair [message #108320 is a reply to message #108316] Sun, 12 December 2010 11:16 Go to previous messageGo to next message
midlf is currently offline  midlf   United States
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Registered: July 2007
Location: SE Wisc. (Palmyra)
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Senior Member
Gene - I know it is a JWID. Mine will be also be a JWID. As you note it's gotta be done, hopefully only once if your paying attention here. For owner of 73 & 74's with the 1" thick plywood floors there are recesses routed out on the underside of the floors that the senders fit into. See here:

http://www.gmcmhphotos.com/photos/showphoto.php?photo=24748&title=getting-started&cat=4936

I would advise, at least, drilling a small, 1/8" pilot hole through the floor so you can locate the precise center of your cut if you should want to cut the floor to get at the sender. I have plans to make a large hole with a cover plate before I put my tanks back in. Pictures will be posted when I do it.


Steve Southworth
1974 Glacier TZE064V100150 (for workin on)
1975 Transmode TZE365V100394 (parts & spares)
Palmyra WI
Re: [GMCnet] Gas Tank Sender repair [message #108323 is a reply to message #108320] Sun, 12 December 2010 11:22 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
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Registered: August 2005
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Senior Member
yep
the problem is, the cut-outs are almost never centered over the senders, so
using the Dec Plates (from West Marine) I had to make the hole fit the deck
plate and the sender location

good luck
gene


On Sun, Dec 12, 2010 at 9:16 AM, Steve Southworth <midlf@centurytel.net>wrote:

>
>
> Gene - I know it is a JWID. Mine will be also be a JWID. As you note it's
> gotta be done, hopefully only once if your paying attention here. For owner
> of 73 & 74's with the 1" thick plywood floors there are recesses routed out
> on the underside of the floors that the senders fit into. See here:
>
>
> http://www.gmcmhphotos.com/photos/showphoto.php?photo=24748&title=getting-started&cat=4936
>
> I would advise, at least, drilling a small, 1/8" pilot hole through the
> floor so you can locate the precise center of your cut if you should want to
> cut the floor to get at the sender. I have plans to make a large hole with
> a cover plate before I put my tanks back in. Pictures will be posted when I
> do it.
> --
> Steve Southworth
> 1974 Glacier TZE064V100150
> Palmyra WI
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>



--
Gene Fisher -- 74-23,77PB/ore/ca
“Give a man a fish; you have fed him for today --- give him a URL and
-------
http://gmcmotorhome.info/
Alternator Protection Cable
http://gmcmotorhome.info/APC.html
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Re: [GMCnet] Gas Tank Sender repair [message #108343 is a reply to message #108323] Sun, 12 December 2010 13:32 Go to previous messageGo to next message
WD0AFQ is currently offline  WD0AFQ   United States
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Gene, I do like what you did. My problem is that Teri does not wnat me to mess up the hardwood floor. Any suggestions?
Dan


3 In Stainless Exhaust Headers One Ton All Discs/Reaction Arm 355 FD/Quad Bag/Alum Radiator Manny Tran/New eng. Holley EFI/10 Tire Air Monitoring System Solarized Coach/Upgraded Windows Satelite TV/On Demand Hot Water/3Way Refer
Re: [GMCnet] Gas Tank Sender repair [message #108346 is a reply to message #108343] Sun, 12 December 2010 13:56 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
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Registered: August 2005
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Senior Member
have been thinking about that,and I think a hidden panel is the way to go.

you could make a wood panel that had hidden seams

since the holes are in the haul, something that went wall to wall could
work.

take pictures ;>)
gene



On Sun, Dec 12, 2010 at 11:32 AM, Dan Gregg <gregg_dan@hotmail.com> wrote:

>
>
> Gene, I do like what you did. My problem is that Teri does not wnat me to
> mess up the hardwood floor. Any suggestions?
> Dan
> --
> Dan & Teri Gregg
>
> http://danandteri.blogspot.com/
>
>
>
>
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>



--
Gene Fisher -- 74-23,77PB/ore/ca
“Give a man a fish; you have fed him for today --- give him a URL and
-------
http://gmcmotorhome.info/
Alternator Protection Cable
http://gmcmotorhome.info/APC.html
_______________________________________________
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Re: [GMCnet] Gas Tank Sender repair [message #108350 is a reply to message #108346] Sun, 12 December 2010 14:54 Go to previous messageGo to next message
WD0AFQ is currently offline  WD0AFQ   United States
Messages: 7111
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Location: Dexter, Mo.
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Senior Member
Gene, good idea.
dan


3 In Stainless Exhaust Headers One Ton All Discs/Reaction Arm 355 FD/Quad Bag/Alum Radiator Manny Tran/New eng. Holley EFI/10 Tire Air Monitoring System Solarized Coach/Upgraded Windows Satelite TV/On Demand Hot Water/3Way Refer
Re: [GMCnet] Gas Tank Sender repair [message #108352 is a reply to message #108343] Sun, 12 December 2010 14:56 Go to previous messageGo to next message
fred v is currently offline  fred v   United States
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Registered: April 2006
Location: pensacola, fl.
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Senior Member
WD0AFQ wrote on Sun, 12 December 2010 13:32

Gene, I do like what you did. My problem is that Teri does not wnat me to mess up the hardwood floor. Any suggestions?
Dan

maybe do what they do in boats. cut in a hatch and make a nice border trim around it and the opening.!!??


Fred V
'77 Royale RB 455
P'cola, Fl
Re: [GMCnet] Gas Tank Sender repair [message #108361 is a reply to message #108323] Sun, 12 December 2010 15:31 Go to previous message
USAussie is currently offline  USAussie   United States
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Registered: July 2007
Location: Sydney, Australia
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Senior Member
Gene,

I ran out of time at the COOP this year and never got to:

1) Drop both tanks & remove the sender from one of them
2) Make a 1/2" round wood block the size of the recess the sender sits in
3) Put a sharp screw in the center of the block
4) Tape the block in the sender recess
5) Raise the tank into the AUX tank position
6) Press the tank upwards so the screw can mark the aluminum sheet
7) Lower the tank and drill a 1/8" hole at the mark
8) Repeat the process for the MAIN tank

You now have the EXACT center of both the senders and can use a circle
cutter to cut a hole through the floor for access.

Regards,
Rob M.
USAussie - Downunder


-----Original Message-----
From: gmclist-bounces@temp.gmcnet.org
[mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of Mr.erf ERFisher
Sent: Monday, December 13, 2010 4:23 AM
To: gmclist@temp.gmcnet.org
Subject: Re: [GMCnet] Gas Tank Sender repair

yep
the problem is, the cut-outs are almost never centered over the senders, so
using the Dec Plates (from West Marine) I had to make the hole fit the deck
plate and the sender location

good luck
gene



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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
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