3b air in fuel lines. Bleeding advice (1 Viewer)

Joined
May 26, 2014
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18
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Kelowna BC
Hey guys, I've not had much luck with the factory service manual. I've replaced a leaky fuel hose going to the fuel filter and followed all the steps in bleeding the system with the priming pump and at the injection spots (as per the owners manual) . However, the truck still has a hard hard time starting. I have to turn it over for almost 30 to 45 seconds to get it to start. Once started however, it runs like a champ. I've circled the hose I replaced in red and the yellow circles are the areas I've bled. I guess my question is this. Can a little air really hamper starting the truck the badly. How long should I let the injector connections stay open to purge all the air? Should I keep pumping the primer pump (I swear, I put a gallon through at least) Any other suggestions? It is annoying to take so long to start and I sense that it is hard on the engine and starter.

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Joined
May 22, 2012
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462
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Ontario, Canada
This may be a double trouble. Just replace all of the fuel lines and hose clamps. Another one may also be allowing air ingress.
start at the fuel tank and replace everything to the pump. I've had hose clamps rot out or loosen off.

Air ingress will kill a running motor very quickly. Are you sure you don't have a glow plug problem?
When 1 glow plug dies the engine will usually still start after a few too many cranks. When 2 plugs die it takes like 45 seconds of cranking to get it to fire
 
Joined
May 26, 2014
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Kelowna BC
Hey Cruising. My only thought is that the truck started perfectly prior to replacing this fuel hose. I don't think there is any air ingress at these new banjo bolt spots as a replaced all the washers (as per factory service manual recommendation). Near the glow plugs are the injector connections. The owners manual said if it doesn't start to crack them open and bleed them. How long would you suggest having them opened to bled all the air out? I could replace the glow plugs but honestly, them seemed to be in proper working order prior to replacing this hose.
 
Joined
Jun 20, 2007
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952
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Tahsis, BC
Don't forget there's a diesel section ;)

I've had mild air leaks that have resulted in smokey/spluttery warmups at altitude and in the cold for some time now. However, provided the glow plugs are connected and batteries are good, have never had to give it more than a quick crank - and my engine is not young!

I would second the double trouble. Check and double check everything glow plug related. This has got me and many others in the past.
 
Joined
May 26, 2014
Messages
18
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Kelowna BC
I'll certainly check the glow plugs, it is just hard to believe that they would suddenly become faulty when when they didn't have anything to do with the fuel line I changed out. After it is running, it is easy to start so maybe there is something to the glow plugs in that they are already warm. Hmm.
 
Joined
May 26, 2014
Messages
18
Location
Kelowna BC
Changed out the glow plugs and still the trouble starting. I've tried to test the glow plugs as per the factor service manual and they don't seem to get any voltage (or voltage drop). Weird. Provided that I did it correctly (one end on the top of the glow plug the other end grounded to the truck), it didn't measure any voltage. Glow plug resistor? I'm guessing I should have put this in the diesel section. Apologies guys, I'll remember that next time.
 
Joined
May 26, 2014
Messages
18
Location
Kelowna BC
I've got some follow up info. There is a wire that is attached the the last glow (the glow plug closest to the back of the engine bay, red lines around it). I traced that wire to the glow plug warming button. When I take it off and connect it to the multi meter, press the button , I get 12 volts. However, when I attach it to the glow plug I get nothing. Does that make any sense. If the wire is attached to the metal bar that connects all 4 glow plugs (I 'm assuming to provide each of them the voltage required to warm them), should I not be able to measure 12 volts across that entire bar when I press the warming button?

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Joined
Jun 20, 2007
Messages
952
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Tahsis, BC
Here's a quick test to see if your plugs are connected - turn the key just so your gauges light up and the bettery indicator shows voltage (should be near 12). Now turn it further so the glow plug light turns on - you should notice the battery meter drop below 12V. If it doesn't move at all when the glow plug light turns on, your plugs aren't even connected.
 
Joined
May 26, 2014
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Kelowna BC
Hey Josh, maybe the 70's are different or something, i've got acc then on. Nothing happens with acc, and when I turn it to on, then the gauges come to life. However, you did prompt a good idea. When I turn to on, the battery goes up to approx 12. When I try my blinkers the gauge moves, turn the heater on it moves, however, when I press the glow plug warming button nothing happens. Should the battery charge gauge move as well? I'd think so . INteresting.
 
Joined
Jun 20, 2007
Messages
952
Location
Tahsis, BC
Hey Josh, maybe the 70's are different or something, i've got acc then on. Nothing happens with acc, and when I turn it to on, then the gauges come to life. However, you did prompt a good idea. When I turn to on, the battery goes up to approx 12. When I try my blinkers the gauge moves, turn the heater on it moves, however, when I press the glow plug warming button nothing happens. Should the battery charge gauge move as well? I'd think so . INteresting.

Yeah it should move a tiny bit for those things and a LOT for the glow plugs. My guess is, when you were fiddling around with your fuel lines you accidentally unplugged one of the links that sends them power. I've done this before and spent literally days in the Chilean desert trying to figure out why my engine wouldn't start.

Look at all your fuses, but also look around in the engine compartment for any electrical connections that are disconnected. On my 60 it's a little link next to the battery on the driver's side. (It currently functions as my security system because it's loose enough to disconnect itself every time I drive, so you can't start the engine without opening the hood and connecting it)
 

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