PD4106 1964 saga continues

[agetme]

Thanks for previous info.

I purchased the bus, drove it home and parked it in my storage area.
Next day went out started it ran fine, in my excitement i let it run it died. Started fine but died
shortly after. Started again but ran down and died. After several days i came to the conclusion that i ran it out of
fuel. Tried many times now to start it, no smoke so no fuel (my thoughts).
Looked on fourm did a search found threads on prime issues.
Yesterday i installed a fuel pump, i put it at in the engine compartment directly inline on the line coming in to the
fuel filters. Did not work, will not pull from tank. Oh i did refill the tank with at least 30-45 gallons of fuel.

Can i not put it in the engine compartment? To far to pull?
There are 3-4 lines coming out ot the tank. I know 1 of them goes over to the GEN. Only 1 heads back to the engine.
It is the same material that the line into the fuel filters is made of. The rest of the lines coming out of the fuel tanks'
are metal and head forward or up into the bus.

I guess i will relocate the fuel pump onto the tank area to see if that works.

It is a world into it's self working on these things. I am a 25 year airplane mechanic/electrical experienced person but do not know buses. Having fun with it mostly.

Thanks

Tom Hamilton IN Denver.

P.S. might be asking for a name of a mechanic soon

[Timkar]

Hi Tom,
Sounds like either a collapsed fuel line or a split one (sucking air)
Can you use a 5 gal fuel can close to the pump to serve as temp supply?
At least that way you will be able to prime it and see if it is your fuel line.
i am sure the experts will be along shortly.....
HTH....Tim

[fortyniner]

In the engine compartment there is a small bracket where the engine fuel lines connect to the hard lines running from the
fuel tanks. One of these hardlines has a small cylindrical check valve where it connects to the bracket. The other line is the fuel return line. If you disconnect the engines return line at the bracket and submerge it in a can of fuel while cranking with the rear start switch, no bubbles should appear after the first few. Also you can verify its getting good fuel flow as well. Be very careful with your starter. The brush holders will distort from heat if you crank for more than about 5 seconds without a 30 second rest in between. These buses can be hard to re-prime once air gets into the system.

If you find you have good flow with no air bubbles the problem is some where else. Maybe the governor.
Tom P.

[agetme]

I took the tank side of the 12v fuel pump ran a hose to a can of fuel. Bus started and ran fine.

I moved the fuel pump to the tank area and connected it to the feed line at the tank. Primed bus ran fine.
New problem showed up. Now that it will start and run there is an air connection that you can hook air
tools up to with a gauge. If the air pressure gets to 40 psi a piston on the fuel box on the engine moves and pushes a curved arm that causes the engine to die. If i open the hand valve on the air connection and keep the air pressure below 35 the arm does not move and shut the engine off.
However i went to the front area driver seat and noticed the air was not building up. All this work fine when i brought the bus home and before i ran it out of fuel.

Any ideas would be helpful on the air solenoid arm pushing the curved arm and shutting the engine off.


Did get it running at least, prime established and fuel pump in line so future priming should be easy.

Thanks for the help, the idea to put the fuel line in a container of fuel was great.

Tom H

[luvrbus]

Check the rear start make sure it is in the run position and dash switch is on if not when the air build up it shuts it down

[fortyniner]

Thats correct. Thats the fuel stop lever. The little air cylinder is controlled by an electric air valve up on the firewall.   The stock 4106 has a big master knob. It should be in the "day" position to start and both rear switches switches up in the normal position. To start from rear only the center switch needs to be moved to "rear start". Once started move it back to normal otherwise the alternator won't charge.

-Tom Phillips

[Cary and Don]

I think every one of us did this when we brought our bus home.  There should be a sticky post at the top of the board for this one.  It's often the first question from a new owner.  We called the previous owner and it took him awhile to figure out what we had done.  Very embarrassing.

Don and Cary
1973 05 Eagle
GM 4107
Neoplan AN340

[agetme]

Thanks for the great info. Saved me much stress as i was already stressing over the start issue.

All good now, on to some other issues.

Tom H