1978 All Other Makes Recreational Vehicles Fuel delivery question

Tiny
JOHNHLONG
  • MEMBER
  • 1978 ALL OTHER MAKES RECREATIONAL VEHICLES
  • V8
  • 2WD
  • AUTOMATIC
  • 136,000 MILES
I have a 1978 Winnebago Brave motor home. Just starting to get it running after sitting for 10 years. When I look at the clear fuel filter I see fuel squirting through it at irregular volumes. Should fuel delivery be a constant? Should the fuel filter remain full of fuel or am I see some kind of fuel supply problem? John
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Friday, October 10th, 2014 AT 8:49 PM

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Tiny
CJ MEDEVAC II
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I'D PROBABLY SAY YOU HAVE A MECHANICAL FUEL PUMP

IT IS NORMAL FOR THE FUEL TO "PULSE" AS THE FUEL PUMP "PUMPS" OFF OF AN ECCENTRIC LOBE ON THE CAMSHAFT

AS FAR AS FUEL IN THE FILTER, IT IS NORMAL FOR IT NOT TO BE FULL/ IT MAY VARY DEPENDING ON RPMs AND DEMAND

HOWEVER, ***NOT THAT YOU NEED TO DO THIS***, BUT IF YOU WANNA SEE IT FULL ALL OF THE TIME ADD TO/ REROUTE THE FUEL HOSES TO IT SO THAT THE FILTERS INLET IS "DOWN" AND THE OUTLET IS "UP" (FUEL MUST THEN CLIMB THRU THE FILTER TO GET THRU IT - INSTEAD OF BEING HORIZONTAL AND "RUNNING OUT" FAST)
THERE IS NOTHING WRONG WITH HORIZONTAL!

FOR A TEST ON YOUR FUEL VOLUME, TAKE THE FUEL HOSE LOOSE AT THE CARB (ADD TO IT?) STICK IT IN A QUART JAR. START IT UP FOR ABOUT 30 SECONDS [IT WILL RUN OFF THE FUEL IN THE BOWL] YOU SHOULD GET ABOUT 1/2 A QUART (1 PINT) OF FUEL IN YOUR TEST JAR

WITHOUT A BOOK ON YOUR ENGINE, I'D SAY YOUR FUEL PRESSURE WILL BE BETWEEN 5 AND 7 PSI IF YOU INSTALL A GAUGE ON THE LINE

BELOW I'M INCLUDING A PIC OF MY JEEP CJ-5s FUEL SYSTEM, SO YO CAN SEE THE "LOW PRESSURE" FUEL GAUGE I HAVE INSTALLED PERMANENTLY UNDER THE HOOD (YOUR SYSTEM MAY NOT HAVE A RETURN LINE BACK TO THE FUEL TANK AS MY JEEP DOES)

YOU MIGHT DO A FULL 100% TUNE UP/ DRAIN REPLACE YOUR OLD FUEL/ MAYBE A CAN OF SEAFOAM TO CLEAN UP "MR. CARBURETOR" (IF IT'S NOT IN NEED OF A REBUILD

INSPECT THEM BRAKES REALLY GOOD, THEY MAY BE RUSTY AND POSSIBLY SEIZED, OR CLOSE TO IT. I'VE DEALT WITH JEEPS THAT SAT A LONG TIME AND THE WHEEL CYLINDER PISTONS WOULD NOT MOVE, OR ONLY ONE SIDE OF IT WOULD (IN OTHER WORDS, 1 SHOE WOULD WORK, THE OTHER WOULD NOT)

LEMME KNOW IF THIS HELPS AT ALL

THE MEDIC
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Friday, October 10th, 2014 AT 9:36 PM
Tiny
MHPAUTOS
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This is quite normal for a petrol engine with a mechanical pump.
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Saturday, October 11th, 2014 AT 6:30 AM
Tiny
JOHNHLONG
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Thanks,

I won't worry as much about it.

John
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Saturday, October 11th, 2014 AT 7:10 AM
Tiny
MHPAUTOS
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If you have any other issues please post here.
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Saturday, October 11th, 2014 AT 3:26 PM
Tiny
MIKE H R
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Is it running, make sure you clean out the fuel tank. It there was gas with entenal I would replace with new gas that is if you have not done it yet. Check all the lines to see they are brittle. Add a gas booster to help get rid of any water that had gotten in the tank.
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Tuesday, October 28th, 2014 AT 5:28 PM

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