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[GMCnet] Vapor lock cures (long) [message #181765] Sat, 25 August 2012 19:58 Go to next message
Gerald Work is currently offline  Gerald Work   United States
Messages: 102
Registered: June 2010
Karma: 0
Senior Member
Several have asked off line what electric pump and set up I use. I like the kit from JimK. It has the pump, a large canister style fuel filter, the proper check valve and the required hardware. The pump is a low pressure Carter. I ran a line from the output of the selector valve to the outside of the frame rail. That goes to a T with one leg going to the electric fuel pump and the other to a bypass. A check valve allows the fuel to be drawn by the mech. Fuel pump around the electric pump or to be pushed by the electric pump to the mechanical pump. Yup, there is a very small chance that the electric pump would push gas into the crank case if the diaphragm ruptured in the mech. pump, but I only run the electric for short periods at a time as it is noisy the way I have it mounted. I have it wired to come on via a toggle switch on the wall near my left leg at about the same height off the floor as the headlight switch. Some like to wire through an oil pressure switch so
the electric pump goes off if the engine shuts down. I just have to remember to turn it off if it happened to be on at the time the engine shut down. Others like to wire it through the fuel selector valve and plumb the inlet to the electric pump to the outlet of just the aux tank. That likely works for flat land driving, but not necessarily for mountains such as where we live. This arrangement works well for me and the electric pump is only on if I experience vapor lock and it goes off immediately when the vapor lock abates. The Toro mech. pump is exactly the same for Toros with AC and those without except the one for AC has two outlet nipples in the top cover. No check valves or anything else, just the two outlets so you can plug one if you do not want the recirc. feature which did not work for me.

Jerry Work
The Dovetail Joint
Fine furniture designed & hand crafted
in the 1907 former Masonic Temple building
in historic Kerby, OR
Http://jerrywork.com
..........
Message: 4
Date: Sat, 25 Aug 2012 07:56:46 -0700
From: Gerald Work <glwork@me.com>
Subject: [GMCnet] Vapor lock cured (long)
To: "gmclist@temp.gmcnet.org" <gmclist@temp.gmcnet.org>
Message-ID: <A2BA1DE7-C7A6-4DE7-A0A3-DD9681AEF370@me.com>
Content-Type: text/plain; CHARSET=US-ASCII

I tried a Toro mech fuel pump with the return line some time ago and found it did not stop the vapor lock as it was supposed to do. An electric fuel pump just forward of the selector valve that I turn on only when needed does stop it. This three thousand plus mile trip is a good example. While in Canada where we could run on no ethanol gas I never experienced vapor lock even pulling the 13% grades or the 11% 20km grades when it was hot. Got back to the states on premium crap gas and experienced vapor lock on long hills when hot. Flip on the electric fuel pump and the vapor lock instantly stops. Flip it off at the top of the hills and continue on. Works for me.

Jerry Work
The Dovetail Joint
Fine furniture designed & hand crafted
in the 1907 former Masonic Temple building
in historic Kerby, OR
Http://jerrywork.com
..............
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Re: [GMCnet] Vapor lock cures (long) [message #182443 is a reply to message #181765] Thu, 30 August 2012 16:56 Go to previous message
James Hupy is currently offline  James Hupy   United States
Messages: 6806
Registered: May 2010
Karma: -62
Senior Member
Jerry, I had a toro pump second outlet stress fracture and leak gas onto my
headers in Banff. Took a mickey mouse fix in Pocahontas Campground and
outside a NAPA store with a hacksaw, 21/32" drill, 1/8" pipe tap, and a
brass pipe plug wrapped in teflon tape to stop the leak. Drove to Jasper,
no pumps, then on to the next town where I bought two non A/C mech pumps, 2
4070 Carter Elec pumps, and fittings. $595.00,
WOW. No more A/C pumps for me.
Jim Hupy
Salem, OR
78 GMC Royale 403 (currently in Benton Harbour, MI, on the way home.)

On Sat, Aug 25, 2012 at 8:58 PM, Gerald Work <glwork@me.com> wrote:

> Several have asked off line what electric pump and set up I use. I like
> the kit from JimK. It has the pump, a large canister style fuel filter,
> the proper check valve and the required hardware. The pump is a low
> pressure Carter. I ran a line from the output of the selector valve to the
> outside of the frame rail. That goes to a T with one leg going to the
> electric fuel pump and the other to a bypass. A check valve allows the
> fuel to be drawn by the mech. Fuel pump around the electric pump or to be
> pushed by the electric pump to the mechanical pump. Yup, there is a very
> small chance that the electric pump would push gas into the crank case if
> the diaphragm ruptured in the mech. pump, but I only run the electric for
> short periods at a time as it is noisy the way I have it mounted. I have
> it wired to come on via a toggle switch on the wall near my left leg at
> about the same height off the floor as the headlight switch. Some like to
> wire through an oil pressure switch so
> the electric pump goes off if the engine shuts down. I just have to
> remember to turn it off if it happened to be on at the time the engine shut
> down. Others like to wire it through the fuel selector valve and plumb the
> inlet to the electric pump to the outlet of just the aux tank. That likely
> works for flat land driving, but not necessarily for mountains such as
> where we live. This arrangement works well for me and the electric pump is
> only on if I experience vapor lock and it goes off immediately when the
> vapor lock abates. The Toro mech. pump is exactly the same for Toros with
> AC and those without except the one for AC has two outlet nipples in the
> top cover. No check valves or anything else, just the two outlets so you
> can plug one if you do not want the recirc. feature which did not work for
> me.
>
> Jerry Work
> The Dovetail Joint
> Fine furniture designed & hand crafted
> in the 1907 former Masonic Temple building
> in historic Kerby, OR
> Http://jerrywork.com
> ..........
> Message: 4
> Date: Sat, 25 Aug 2012 07:56:46 -0700
> From: Gerald Work <glwork@me.com>
> Subject: [GMCnet] Vapor lock cured (long)
> To: "gmclist@temp.gmcnet.org" <gmclist@temp.gmcnet.org>
> Message-ID: <A2BA1DE7-C7A6-4DE7-A0A3-DD9681AEF370@me.com>
> Content-Type: text/plain; CHARSET=US-ASCII
>
> I tried a Toro mech fuel pump with the return line some time ago and found
> it did not stop the vapor lock as it was supposed to do. An electric fuel
> pump just forward of the selector valve that I turn on only when needed
> does stop it. This three thousand plus mile trip is a good example. While
> in Canada where we could run on no ethanol gas I never experienced vapor
> lock even pulling the 13% grades or the 11% 20km grades when it was hot.
> Got back to the states on premium crap gas and experienced vapor lock on
> long hills when hot. Flip on the electric fuel pump and the vapor lock
> instantly stops. Flip it off at the top of the hills and continue on.
> Works for me.
>
> Jerry Work
> The Dovetail Joint
> Fine furniture designed & hand crafted
> in the 1907 former Masonic Temple building
> in historic Kerby, OR
> Http://jerrywork.com
> ..............
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
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