Bleeding a diesel engine

For the very first time in some 60 years of driving, I ran out of fuel yesterday. Der Klunker ('81 300SD) suddenly started sputtering and stumbled to a halt, luckily in a parking lot. Opened the hood. Sure
enough, no fuel in the sight glass. A couple of kind gentlemen helped me push the car out of the way and in due course road service arrived with two gallons of diesel fuel. They were concerned that it would be very hard to get a diesel that has been sucking air to start without a lot of work. If this had been my boat they would have been entirely correct. But this car has a built-in priming pump on the engine. A few strokes on the pump, the sight glkass filled up and a few more strokes later a hissing sound confirmed that the byapass valve on the injectopr pump had openen meaning the pump was now ready to send fuel with no air to the injectors. She started with a couple of turns on the starter.
Now, why can't boat diesel engines be set up like that? I live in terror of the boat engine sucking air becaise it will stop and bleeding the system in a seaway or even at the dock is an exercize in contortion and I don't pretzileize so well anymore.
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Running out of fuel when "on the high seas" has a lot more problems than air in the fuel lines! And your boat's fuel tank is a lot larger than 18 gallons - as you well know when the fuel bill is presented.
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says...

The car is eighteen gallons? The road service guys put in two gallons and half a block later at the gas station I put in 19.56 gallons. It would seem there is a reserve. The fuel guage is pretty reliable and I generally have sense enoughg never to go less than 1/4. But lately it has been bouncing between empty and 1/4. I generally pay more attention to the mileage but this tankful came up just a wee bit short.
As for the boat, thank God it's a sailboat. It only has a twenty gallon tank and uses only a gallon an hour. Of course, that works out to about 5 mpg :) But between the boat and the car we have been spending a lot on diesel at $3+ per gallon.
Boat in the slip next to us is a power boat with a 450 gallon fuel tank. He bought the boat last year when diesel at the dock was under $2. He did not use the boat much this year.
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Gogarty wrote:

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Well you can make things a little easier on yourself: - Racor has a fuel filter with a built-in hand pump -or you could install an electric pump in the fuel system -only open the bleed screw on the injector pump, at least as a first try. My experience (with Yanmars) is that if you pump fuel to the injector pump the engine will start, run rough, and then operate normally. No need to bleed injectors. -my other experience with Yanmars is that the hand lever on the engine fuel pump is pretty useless for bleeding, hence my addition of the Racor filter with pump.
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tank. Would a bypass switch to activate this pump make bleeding easier? Is the hand pump on the engine a type that will pass fuel through if pressurized from upstream?
--

Roger Long





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wrote:

================================== That's a fairly commom practice on larger power boat diesels. It makes filter changes a lot easier and removes uncertainty about the ability to get started again. My setup uses a Walbro 6802 fuel pump with a switch and a couple of small bypass valves on each engine. I have a third Walbro that can be valved to bypass the backup generator, thus serving as a dockside fuel polishing system by constantly circulating fuel through the Racor filters.
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wrote

I would say yes to both questions. If I use the pump on my Racor filter it sends fuel past the engine pump and out the injector bleed screw.
I forgot to mention another trick is to get someone to hold down your compression release lever, or jam it down, and then spin the engine with the starter while the injector pump bleed screw is open. This seems to work the engine mounted fuel pump a lot faster than you can by hand and will shoot fuel out of the bleed screw. Best to cover with a rag.
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still takes a contortionist.
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Gordon Wedman wrote:

I spent half a day trying to bleed mine after cleaning the Racor filter and finally gave up and called a mechanic. A $100 lesson I remember well. He took it all apart and installed a squeeze hand pump on the line between the tank and the Racor. Now I pop off the Racor, replace the filter, place the top of the Racor back on and squeeze the pump until fuel leaks out the Racor a little then tighten it up. I haven't had a problem since changing filters. I don't believe I've had air in the line between the Racor and injectors but opening the injectors and squeezing the hand pump would probably fix that also without too much work.
--
Bill Boyher
s/v Summer Rose
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Isn't a squeeze bulb illegal, or against some CG standard on INBOARD engines? Thought I read that some place.....???
I like the idea, by the way, and used it on a Sea Rayder with the V-6 Mercury Sport Jet inboard....worked great.
Your insurance company might NOT like it, however....
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Well I doubt that all that '"Hand Pumping" would move any fuel between the Injector Pump and the injectors even if you disconnected all the lines at the injectors. The Injector Pump will block all fuel flow until it is actually driven by the crankshaft. Nice thought thought, to bad it isn't true.
Me
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I ran out of diesel with my MB Sprinter (van) a while back, after putting a jerrycanful in I tried starting a few times, but it wouldn't start. Luckily I read the manual before I emptied te battery: It bleeds automatically, but you have to use the starter for 50 seconds non-stop; worked like a charm.
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The newer diesel engines (OM60x) since mid 80s can bleed themselves, but take a while non-stop. 50 seconds is good. I thought 2 minutes is also normal.
Older diesel (OM61x) like the one in 81 300SD uses hand pump.
Inigo Montoya wrote:

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