Author Topic: Electric Fuel Pump Install  (Read 2940 times)

Offline GnarlyBus

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Electric Fuel Pump Install
« on: April 11, 2019, 01:59:45 PM »
It's time to install my Airtex Electric Priming Pump in the engine bay right before the primary fuel filter. If I remove the fuel line right before that filter that ties in up above, will diesel keep flowing from the tank or not? I don't see any kind of shutoff in the manual. Do I need to plug it up above? I wanna be prepared!

Inspired by this post: https://www.busconversionmagazine.com/forum/index.php?topic=30033.0
1984 MC-9 w/ 6v92TA & Allison 740
Oregon Summers & Arizona Winters
Full-Time since 2015

Offline buswarrior

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Re: Electric Fuel Pump Install
« Reply #1 on: April 11, 2019, 05:08:36 PM »
fuel will only flow if the level in the tank is above where you crack it open.

An excellent upgrade!

Happy coaching!
Buswarrior
Frozen North, Greater Toronto Area
new project: 1995 MCI 102D3, Cat 3176b, Eaton Autoshift

Offline chessie4905

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Re: Electric Fuel Pump Install
« Reply #2 on: April 12, 2019, 05:00:19 AM »
OMG! It's going to shoot out like a fire hose!!😱 Seriously though, the fitting on the firewall is above the top of tank. That's why they have a check valve there to keep fuel from returning to tank and losing prime. BTW, make sure you don't connect it in the return line. Just saying..lol
GMC h8h 649#028 (4905)
Pennsylvania-central

Offline richard5933

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Re: Electric Fuel Pump Install
« Reply #3 on: April 12, 2019, 05:15:22 AM »
The tech at the shop installing my Jakes wanted to test all the new fuel lines before firing up the engine. He removed the front plug on the secondary filter and attached his electric fuel primer to that port.

There's a similar port on the front of the primary filter housing. Could that be used as the connection point for the electric pump being discussed here?
Richard
1974 GMC P8M4108a-125 Custom Coach "Land Cruiser" (Sold)
1964 GM PD4106-2412 (Former Bus)
1994 Airstream Excella 25-ft w/ 1999 Suburban 2500
Located in beautiful Wisconsin

Offline lostagain

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Re: Electric Fuel Pump Install
« Reply #4 on: April 12, 2019, 06:42:04 AM »
I installed my priming fuel pump just outside the tank beside the fill neck. This way it doesn't have to suck fuel very far, and pushes it the rest of the way.

JC
JC
Blackie AB
1977 MC5C, 6V92/HT740 (sold)
2007 Country Coach Magna, Cummins ISX (sold)

Offline GnarlyBus

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Re: Electric Fuel Pump Install
« Reply #5 on: April 18, 2019, 05:14:16 PM »
Finished my priming pump install. I did consider attaching the pump to the primary filter housing and keeping the same hose but opted to do it this way.

After inspecting the hose I took off, I noticed very tiny cracks on the outside. Inspect your hoses people! I had new ones made and wired up the pump. Then I added a switch to the rear panel.

The ball valve right before my primary fuel filter was replaced as well.

I'll be switching new fuel filters in the easy way from now on!
1984 MC-9 w/ 6v92TA & Allison 740
Oregon Summers & Arizona Winters
Full-Time since 2015

Offline chessie4905

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Re: Electric Fuel Pump Install
« Reply #6 on: April 18, 2019, 06:12:51 PM »
I would securely mount the pump, not just let it hang like that.
GMC h8h 649#028 (4905)
Pennsylvania-central

Offline GnarlyBus

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Re: Electric Fuel Pump Install
« Reply #7 on: April 19, 2019, 03:01:48 PM »
I would securely mount the pump, not just let it hang like that.

Mounted it with a modified L bracket. Need to add another bolt to the bracket but it's super secure now.
Before I pulled the original fuel hose off, it was ziptied to the big starter wire and run right next to it. Kinda sketchy if you ask me...
1984 MC-9 w/ 6v92TA & Allison 740
Oregon Summers & Arizona Winters
Full-Time since 2015

Offline buswarrior

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Re: Electric Fuel Pump Install
« Reply #8 on: April 19, 2019, 04:27:52 PM »
Busnuts often find lots of zipties, and are fooled into thinking they are the salvation.

Unfortunately, zipties plus vibration cuts hoses.

Zips are a great temp fix, but adding a rubber gromet lined clamp of the correct size for the cable/hose/wire for a proper fix will do the job with reliable finesse.

Happy coaching!
Buswarrior



Frozen North, Greater Toronto Area
new project: 1995 MCI 102D3, Cat 3176b, Eaton Autoshift

Offline Van

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Re: Electric Fuel Pump Install
« Reply #9 on: April 19, 2019, 04:40:34 PM »
Unfortunately, zipties plus vibration cuts hoses.


Happy coaching!
Buswarrior

  C'mon BW! You''re giving all our secrets away :o. How will they ever learn. Lol!  ;D
B&B CoachWorks
Bus Shop Mafia.
Now in N. Cakalaki

Offline richard5933

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Re: Electric Fuel Pump Install
« Reply #10 on: April 19, 2019, 08:08:43 PM »
Busnuts often find lots of zipties, and are fooled into thinking they are the salvation.

Unfortunately, zipties plus vibration cuts hoses.

Zips are a great temp fix, but adding a rubber gromet lined clamp of the correct size for the cable/hose/wire for a proper fix will do the job with reliable finesse.

Happy coaching!
Buswarrior

I carry a few lengths of old rubber heater hose and rubber fuel line in my spares box just for this reason. Combined with a heavy-duty zip tie they make a wonderful makeshift clamp to hold all kinds of things in place.
Richard
1974 GMC P8M4108a-125 Custom Coach "Land Cruiser" (Sold)
1964 GM PD4106-2412 (Former Bus)
1994 Airstream Excella 25-ft w/ 1999 Suburban 2500
Located in beautiful Wisconsin

Offline bevans6

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Re: Electric Fuel Pump Install
« Reply #11 on: April 20, 2019, 07:26:44 AM »
A couple of comments.  Those Airtex pumps suck very well, they have zero issues pulling fuel from the tank when mounted by the engine like that.  You need to be very sure that there is no tension on the hoses, the hoses are too big and stiff for the metal structure of the pump, and if you have a bending force in a hose attached to that pump over time the pump body will bend and start to leak.  I know this because it happened to me...  :)

Last thought - when I first installed mine, I still had the fuel pressure over-ride switch in the starter motor circuit.  If it detects fuel pressure it disables the starter motor.  The pressure from the priming pump would, in some circumstances, trip that switch and disable the starter motor.  Several fun filled hours were spent diagnosing that particular event.


1980 MCI MC-5C, 8V-71T from a M-110 self propelled howitzer
Allison MT-647
Tatamagouche, Nova Scotia

Offline GnarlyBus

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Re: Electric Fuel Pump Install
« Reply #12 on: April 20, 2019, 09:59:44 AM »
That's interesting about the fuel pressure starter kill switch. Mine was disconnected and bypassed before I got the bus. I've considered hooking it back up but I'm very careful not to run the starter for very long anyways. Now I have a better reason to leave it alone.

I got the idea to use the Airtex E8131 from an earlier thread where you said it worked well. So thanks!
1984 MC-9 w/ 6v92TA & Allison 740
Oregon Summers & Arizona Winters
Full-Time since 2015

Offline luvrbus

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Re: Electric Fuel Pump Install
« Reply #13 on: April 20, 2019, 10:08:46 AM »
For years I installed those pump after the primary filter so the pumps don't chance picking up trash,either place will work
Life is short drink the good wine first

 

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