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Author Topic: where is the and what is the best fuel pump to get to gain prime back  (Read 1280 times)
johnjem
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« on: September 29, 2007, 12:30:54 PM »

Where would 1 get a good fuel pump to leave installed in the bus with bypasses system?does napa carry 1 ?where did u guys that have 1 put it and how did u hook it up ps i have a 24 volt system? did u hook it up to primery or secondery filter or fuel line in?
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jlaney
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« Reply #1 on: September 29, 2007, 12:41:22 PM »

hello
when i lost prime on my old scenicruiser with the 871 engine. i tried the air method to no availe. i had an extra water pump like the one in the fresh water line . got some fittings and hooked it up at the primary fuet filter, and use the 12 volt to start it. in no time i had a full stream of fuel from the tank. the problem was trash in the check valve at the tank. leaking fuel back into the tank.  thanks jt.
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j.t. laney  tyler texas 1980 prevost lemirage
johnjem
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« Reply #2 on: September 29, 2007, 03:58:38 PM »

i dont have a problem yet i just installed a recient rebuilt 8v71 and i had all fuel lines open so i am just perpairing to bleed them?
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Len Silva
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« Reply #3 on: September 29, 2007, 04:24:07 PM »

You don't need anything fancy or expensive.  A standard 4-5 psi pump from the auto parts place will be about $25.00.

Here's how I did mine, works great.

You could replace the ball valve with a Detroit fuel check valve but I don't think it's worth the expense.

Len  (no mo oh fo)
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buswarrior
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« Reply #4 on: September 29, 2007, 05:18:27 PM »

From the KISS school....

If installing an aux pump to prime made sence, wouldn't the fleets have done it? Or the factory?

Use a small garden sprayer with fittings for the top of the filters and be done with it.

spend time and money on the other stuff until you run out of other stuff, and then install an aux pump that you don't need when you have nothing else left to do on the coach.

Close ball valve, change filter, fill screw on filter with fuel before re-install. If you have canister filter, use garden sprayer to fill filter. Open ball valve, start bus and floor the throttle for a little while.

Job done.

Virgins in the crowd, expose yourselves now.

yes, Scotch powered this evening....

happy coaching!
buswarrior
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Fredward
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MC-5A #5401 8" roof raise 8V71 with MT647




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« Reply #5 on: September 30, 2007, 10:10:35 AM »

I succumed to the temptation. Here's what I did on my 8-71. By the way, it is a 24volt pump available from Napa installed close to the 24 volt wiring for the starter so no fancy wiring was required. I just hook up an alligator clamp and close the ball valve the once a year I change filters.
Fred
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Fred Thomson
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« Reply #6 on: September 30, 2007, 10:18:12 AM »

why is everyone seememing to be losing prime?

when changing the filter all you have to do is fill them with fuel and start the bus with full throttle application.
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Dallas
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« Reply #7 on: September 30, 2007, 11:12:57 AM »

And to add to what Doug just said....

Make sure they are full to the top, beside the gasket, not down in the hole.

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Len Silva
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« Reply #8 on: September 30, 2007, 11:19:39 AM »

why is everyone seememing to be losing prime?

when changing the filter all you have to do is fill them with fuel and start the bus with full throttle application.

I don't think the issue is changing filters.  Rather, running out of fuel, bad check valve, etc., etc.

Len
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chris4905
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« Reply #9 on: September 30, 2007, 04:41:27 PM »

John,

There are several ways to do it..................

I just removed and installed engines in my 4905, here's what I did.

Went to Napa and got a 24V electric fuel pump.

Used the alternator hot terminal for power for the electric fuel pump.

Your fuel pump has an "in" and an "out" port, both marked.  Get a couple couple gallons of fuel, run a hose from the fuel supply to the "in" port on the fuel pump.  The front of your secondary fuel filter (the smaller one) should have a hex plug on the front of the filter mount.  Remove that hex plug and run a hose from the "out" port on the pump to the fitting you will put on the front of the filter mount.

You can remove the hose from the bulkhead that is the fuel return hose to the fuel tank (if my memory is right as you stand at the rear of the bus looking at the fuel supply and return fittings, the return in the one on the left) so you can see when fuel has reached that point, which means the engine has fuel through it.

When your ready to pump fuel, ground one of the pump wires, and touch the other to the alternator + terminal (the big one) and the pump will run.  Took my pump about 20 seconds of running and fuel started coming out of the return line to the fuel tank.

You can of course mount it somewhere in the engine compartment, or put it in one of your bays until the next time.

Good luck,
Chris
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Chris & Cheryl Christensen
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Fredward
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MC-5A #5401 8" roof raise 8V71 with MT647




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« Reply #10 on: September 30, 2007, 04:59:35 PM »

tekebird:
I have cartridge filters, not spin on so I can't fill them. Its real easy with the pump and it only took about 20 minutes to install the pump!
Fred
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Fred Thomson
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