Lister Engine Forum

Lister Engines => Listeroid Engines => Topic started by: mike90045 on November 30, 2018, 06:32:54 PM

Title: ran fuel dry
Post by: mike90045 on November 30, 2018, 06:32:54 PM
Somehow, I didn't turn the fuel on when I started up this AM.  Ran for a good 10 minutes or so, and must have sucked every drop out of the plumbing.  I've bled and have fuel flowing out the top of the pump with the HP line off, but can't seem to get the HP line to blow all the bubbles through.  I'll get a couple good squirts, think it's done, and tighten the upper nut up, and it fires 2 or 3 times, and then air again.  I've rapped all the lines, trying to shake bubbles loose, and rock the flywheel back and forth, getting good squirts out the injector line, but won't keep going .   Is it just full of air foam and have to bleed it all through, or does something bad happen in an IP if it runs dry ?   I use 2 stroke oil in the diesel, 200:1 ratio (ir is that 1:200 ?  4 oz oil per 5 gallons diesel) so the pump shoudl have no damage ?
Title: Re: ran fuel dry
Post by: glort on November 30, 2018, 10:09:47 PM

I have run plenty of diesels out of fuel and never had any damage and never had much problem bleeding ( if you call just turning them over) either to the point I wondered what all the fuss is about? Small engines with plunger pumps never seem to be a worry in my experience.

Weird things can happen with air though.  Are you also sure that there is no leaks getting into thing now you have been fidling with it? Air leaks can be very difficult to find and they have caused me grief when there was plenty of fuel
I think a bit of pressure would help to displace any air and make sure it does not backflow as it were in the system.  Either a pump on the fuel line to the IP or use a well raised Fuel tank of some sort may help. If you have the ability, putting suction on the IP line while turning may help as well.
 In the past I had the engine connected to an electric motor and just spun it up. Didn't take much at all and off it went. My fuel tank was remotely and High mounted though come to think of it.

Got an idea the thing is dry now actually after a hose fell down and seemed to drain all the fuel in the system.
Title: Re: ran fuel dry
Post by: 38ac on December 01, 2018, 01:54:08 AM
Have a two clean rags handy then turn the engine to assure that the fuel pump lifter is all the way down. Loosen the high pressure line at the injector and then remove the high pressure line from the pump and push it aside. Next remove the delivery valve retainer that is under the line you just removed. Be careful as it it comes free as there is a spring under it and set the pieces on the clean rag. Then with you finger lift the delivery valve off the seat until the bubbles clear and then hold it down while tapping the pump inlet line and lift again. Repete until no more bubbles. Usually takes 2-3 tries and takes less time. Reverse the removal order leaving the line loose at the injector, About 10 revolutions you should be getting clear fuel at the injector. Attach line, 2-3 more revs and you should hear the injector creek and your done.

Much easier than hand cranking for 30 minutes and much quicker also.
Title: Re: ran fuel dry
Post by: LowGear on December 01, 2018, 02:05:54 AM
What about putting a bit of air pressure on the tank and then bleed sequentially from the tank?  Seems to work fine on brake bleeds.
Title: Re: ran fuel dry
Post by: mike90045 on December 01, 2018, 06:39:12 PM
Running again !!

 The injector pump was full of foam, which shook loose every time the engine got a good gulp of fuel and the detonation shock blew the bubbles loose.  Then it'd coast a bit, fire, coast.  Much like a hit & miss, only more missing.   I eventually used a wrench at the injector, and bled air every couple of missed fires, and finally got it going.   

I did not pull the Delivery Valve Retainer, it was on awfully tight, and I did not want to wrench that hard on it.  I rocked the flywheel back and forth, pumping each 1/2 rotation, and rapped on the side of the pump to shake bubbles loose, when it finally looked good, I hooked the HP line back up, and got it firing a bit, then bled the upper fitting as it ran.

I don't want to run it dry again. 

adding pic just for fun: