Fuel lines at fuel tank: which is which? - Page 2
 

Fuel lines at fuel tank: which is which?

Started by lostagain, December 14, 2011, 06:07:06 PM

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Oonrahnjay

Quote from: bevans6 on December 16, 2011, 04:45:49 AMDraw-through pump - yes.  works in-line while turned off - yes.  Primes the system in a jiffy  (snip)   Airtex E8131 External Fuel Pump, available many places, in different voltages, and rated for diesel fuel.  (snip) 

    Thanks Brian, very useful.  For all his stupid moves, Mr. Leyland saw fit to put a very effective primer lever on the O-680 engine fuel pump -- it's about the size of your thumb and it makes enough pressure (or suction depending on where you are in the system) to draw fuel through the filters and out through the fuel lines to the injectors so there's no "bleeding" if you run out of fuel, have a filter meltdown, etc.  But it will sure be good to know that prime is right there with the touch of a button on that dark, rainy night when most of the breakdowns seem to occur.

     Thanks for going to the trouble to post this.  BH NC USA
Bruce H; Wallace (near Wilmington) NC
1976 Daimler (British) Double-Decker Bus; 34' long

(New Email -- brucebearnc@ (theGoogle gmail place) .com)

Ed Hackenbruch

Just to complicate things a little, ;D   Brian, your picture shows both a 12 & 24 volt pump. There is a difference in psi. From the pdf file it looks like the one you used is the 24v pump? Does it come in 12v?   JC, did you use the same pump?  12v or 24v, psi?   ???  ;D ;D
Used to own a 1968 MCI 5A and a 1977 5C.

luvrbus

You want to keep the priming pumps at low pressure around 5 to 20 pounds it won't hurt anything they make those up to 115 lbs psi
Nice to see the younger guys doing things that don't work lol you would not believe the heat I gotten over the years for that setup

good luck
Life is short drink the good wine first

Ed Hackenbruch

 I  thought that the lower psi pump would work, but the  main thing i was thinking about was depending on where i put one, i might have 12v easily available instead of 24v.
Used to own a 1968 MCI 5A and a 1977 5C.

bevans6

I bought the pumps at different times for different purposes.  I use the 24v pump in the bus since being an MCI there is 24 volts everywhere.  I have a spare because I lost the first one (found it as I was putting the new one in a safe place to store it while I waited for it to be it's time to get installed.  the new safe place was the same as the safe place I put the first one so I wouldn't lose it.  Yes, I am a "loser"   ;D )

I bought the 12v one to pump solvent through my fuel rails to clean up and loosen up the injectors, which were sticky.  I have a handy 12v power supply for such things, do I bought a 12 v pump.  But it would be the right one for the GM guys with 12 volt power systems, so I put it in the picture too.  On the link there is a different part number for the 12v pump.  If you put that part number in google along with the words "fuel pump", it will give you many places to buy.  I bought mine at Princess Auto.

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

lostagain

Been away on the road since yesterday, in a MacDonald's now with WiFi. The pump I installed is the Airtex E8131, at Princess Auto in Canada. It is the 24V. About 12 to 15 psi IIRC. Fuel will flow through when off. It has a one way check valve too. So it will be off 99.99 % of the time. I'll turn it on when I need to prime. Such as when I replace fuel filters. I thought having it at the fuel tank would be good in case there is a leak  anywhere along the line. Anyway, a nice little winter project now off my list.

Merry Christmas everyone.

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

Van

Clifford, you sir are a bad influence on us youngster's Lol!  ;D
 
B&B CoachWorks
Bus Shop Mafia.
Now in N. Cakalaki

Oonrahnjay

Quote from: lostagain on December 16, 2011, 08:50:49 PMBeen away on the road since yesterday, in a MacDonald's now with WiFi. The pump I installed is the Airtex E8131, at Princess Auto in Canada. It is the 24V. About 12 to 15 psi IIRC. Fuel will flow through when off. It has a one way check valve too.

    Thanks for that, JC.  You are using the same pump that Brian is using.  It's also the one that I'll go with, although I will need a 12V version.

Quote from: lostagain on December 16, 2011, 08:50:49 PMSo it will be off 99.99 % of the time. I'll turn it on when I need to prime. Such as when I replace fuel filters. I thought having it at the fuel tank would be good in case there is a leak  anywhere along the line. Anyway, a nice little winter project now off my list.

     Yes, any air leak in a fuel line will "break suction" and any pump (be it engine-mounted or electrical) will only suck air.  If you have a leak in the fuel line between the electrical pump and the filters and fuel injector pump (or individual injectors or whatever your engine has), you'll get a fuel leak with the pump on.  But at least it will be obvious and you've got a reasonable chance of putting a glop of Gorilla snot on it, covered with a piece of old bicycle inner tube and a hose clamp, and getting on to a place where you can make a permanent repair.  The "obvious" thing is a big benefit too -- a tiny leak in a fuel line that only sees suction will make your life miserable;  and they're d@mned hard to find.

      Thanks again for the help.

Quote from: lostagain on December 16, 2011, 08:50:49 PMMerry Christmas everyone.     JC 

      Merry Christmas to you, too!
Bruce H; Wallace (near Wilmington) NC
1976 Daimler (British) Double-Decker Bus; 34' long

(New Email -- brucebearnc@ (theGoogle gmail place) .com)