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Author Topic: 1.6 NA not getting fuel  (Read 14977 times)

June 04, 2017, 07:36:26 pm

UncleDelicious

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1.6 NA not getting fuel
« on: June 04, 2017, 07:36:26 pm »
I have been working on this Caddy that I bought and I can get it running, but only when the injection pump is pulling fuel from a fuel can directly off the injection pump line.  Once I connect the hose back to the fuel filter, it will just use up the fuel in the pump/line and not pull it from the tank in the truck.
I've tried this twice and it has run until dying with no sign of fuel in the lines around the filter. Does it require more time to draw fuel all the way from the tank up to the injection pump? Or is it possible the lines are just blocked/allowing air in?
I have read elsewhere about pressurizing the fuel return line in order to get fuel up to the filter, but to take care not to over-pressurize the fuel tank. If this is a reasonable strategy to get fuel flowing, what would one use in order to get enough pressure to push through fuel without damaging anything?

I checked around the FAQs and other threads but I didn't see the topic, so I apologize if this has been covered here on a regular basis.



Reply #1June 04, 2017, 08:35:10 pm

drzrma

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Re: 1.6 NA not getting fuel
« Reply #1 on: June 04, 2017, 08:35:10 pm »
Does your fuel filter have a vent? Are you seeing air in the line between the filter and IP when trying to pull from the tank?

Any chance you have a vacuum pump, Mighty Vac or similar like you would use for bleeding brakes? That's what I am using during my continuing adventures, and it's worked quite well for pulling fuel from the tank to the filter and for very gently pulling bubbles through the IP. Not sure how well trying to pressurize the tank would work, but no experience trying it either.

Reply #2June 05, 2017, 12:21:08 am

ORCoaster

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Re: 1.6 NA not getting fuel
« Reply #2 on: June 05, 2017, 12:21:08 am »
Uncle D, Sounds like your problem is either a blocked filter, a blocked line coming to the filter or an air leak in one or the other. 
So do you have fuel in the filter?  How old is that bugger?  If this rig is new to you I wouldn't trust it unless I replaced it myself. 

If you take the banjo fitting off the filter you and remove the fitting easier by cutting it off than pulling on it.  Although I have had luck using a heat gun on those old stiff lines to get it to come off.  Once you have the fitting off you and use some compressed air and blow it down the line and back flush the line to the tank.  Just remember to open up the cap on the tank at the rear of the car.  You don't want to pressurize the tank then remove the air line and have it all come spraying in your face.  That would let you know that you have an open line but I don't think you want that kind of proof.

Put it all back together and look over those copper washers on the fittings real good.  I would use some 600 grit paper and oil and rub them on it and then take a torch to them to anneal them.  Turn them blue then let them cool.  It doesn't take much heat to do that. 

Fill any filter with fuel most of the way full before you attach it to the adapter.  If you have a vacuum source as talked about by drzrma then use it.  The IP only has so much ability to pull fuel to itself.  Once the resistance, like a plugged filter gets to great it just does what you are describing. 

And I hate to even mention this but it could be the IP itself.  It is worn out or scratched inside and just can't pull fuel.  But I wouldn't go there until I knew the filter and line were clean and had low resistance.

Good luck.   ;D

Reply #3June 05, 2017, 12:27:55 am

vanbcguy

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Re: 1.6 NA not getting fuel
« Reply #3 on: June 05, 2017, 12:27:55 am »
It's not terribly unusual for the lift pump section of the injection pump to get sticky if it has been sitting for a while. There's some small metal vanes that pull fuel from the tank, if they stick in their slots they won't create any suction.

Essentially there's two possibilities:

1. You have a plugged line or an air leak
2. Your injection pump isn't actually pulling fuel but otherwise is operating

If it were me I'd get a can of diesel purge, run the engine on it till it's about 3/4 gone then let it sit in the pump for a day or so. Finish it off the next day and go from there. In the meantime try pulling fuel from the filter with a Mityvac or an electric lift pump; the diesel purge is totally a good thing to be doing no matter what. Sort out any fuel system issues in the meantime.



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Reply #4June 05, 2017, 12:37:14 am

ORCoaster

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Re: 1.6 NA not getting fuel
« Reply #4 on: June 05, 2017, 12:37:14 am »
I didn't think about stuck vanes.  That could be the very issue here.  So do the suggested cleaning and purging and I hope that solves the problem.

Reply #5June 05, 2017, 09:04:24 pm

UncleDelicious

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Re: 1.6 NA not getting fuel
« Reply #5 on: June 05, 2017, 09:04:24 pm »
I really appreciate all of the suggestions from everybody. I just ordered a MityVac and I'll swing by AutoZone to get some diesel purge after work some day this week.
I'll let you know how I make out once I get the MityVac up and running

Reply #6June 13, 2017, 01:26:31 am

fatmobile

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Re: 1.6 NA not getting fuel
« Reply #6 on: June 13, 2017, 01:26:31 am »
Put a clear hose on the output of the filter and suck through it.
 You should be able to suck fuel from the tank easily.
 It it's pulling hard there is a restriction.
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with a re-ringed, '84 quantum, turbo diesel, MD block

Reply #7June 17, 2017, 06:51:02 am

UncleDelicious

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Re: 1.6 NA not getting fuel
« Reply #7 on: June 17, 2017, 06:51:02 am »
The MityVac is able to pull fuel up through the filter relatively easily

I was unable to get it to fire back up though due to possibly the starter. I'm going to put the new starter in today and see where that gets me

Reply #8June 17, 2017, 12:02:07 pm

UncleDelicious

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Re: 1.6 NA not getting fuel
« Reply #8 on: June 17, 2017, 12:02:07 pm »
It was starting and running so well from that external fuel supply a couple weeks ago.
I can't even get it to turn over anymore. The starter clicks and that's about all I get, even when jump starting it while trying to start it. I also went around and cleaned up some of the grounds but nothing.

Reply #9June 19, 2017, 05:32:04 pm

kljaja

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Re: 1.6 NA not getting fuel
« Reply #9 on: June 19, 2017, 05:32:04 pm »
I had a "click" noise from starter relay and nothing after with bad battery...
Going fast never killed anyone, suddenly becoming stationary, thats what gets ya

Reply #10June 20, 2017, 05:17:57 pm

fatmobile

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Re: 1.6 NA not getting fuel
« Reply #10 on: June 20, 2017, 05:17:57 pm »
Turn the key to click, then hold it there for awhile.
 Then go feel battery cable ends and starter posts to see what's getting warm,.. that's where your problem is,... if you have a good battery.
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with a re-ringed, '84 quantum, turbo diesel, MD block

Reply #11June 28, 2017, 09:11:02 pm

UncleDelicious

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Re: 1.6 NA not getting fuel
« Reply #11 on: June 28, 2017, 09:11:02 pm »
I'm dumb, the battery was dead, so I guess my jumper cables need to be replaced.
I charged the battery and it starts just fine and runs off the fuel after the filter. It still isn't pulling fuel from before the filter though.
The MityVac pulls fuel through the whole system pretty easily though

Reply #12June 29, 2017, 12:19:51 am

ORCoaster

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Re: 1.6 NA not getting fuel
« Reply #12 on: June 29, 2017, 12:19:51 am »
Maybe time to rebuild the IP if it won't pull through a filter.

Reply #13July 23, 2017, 04:26:32 pm

UncleDelicious

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Re: 1.6 NA not getting fuel
« Reply #13 on: July 23, 2017, 04:26:32 pm »
I've been trying to solve this fuel issue but I can't even check if it's working yet because I've been having electrical problems.

I let the glow plugs warm until the light goes out and then when I turn the key to start I lose all electrics. No headlights, directionals, dash lights, etc.
If I clean off the battery terminals then everything works again until I try to crank it over, rinse and repeat.

Does anybody have a clue what could be the source of this?

Reply #14July 23, 2017, 10:54:30 pm

ORCoaster

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Re: 1.6 NA not getting fuel
« Reply #14 on: July 23, 2017, 10:54:30 pm »
This is the condition better known as electrical Gremlins.  I hate this one but I think the constant cleaning required might be due to heavy load being placed on a contact point that isn't as solid as it should be.  Thus an arc jumps the gap and ruins the little connection that is there.  Might be time for a new battery terminal clamp or a good dose of dielectric grease on it upon assembly.

How about the connection to the ignition key.  The big plug on the right, pull it out and reset it.  I did some dash work a while back and just moving the steering column and dash around made mine a little temperamental. 

Starter connections good on the red cable?  That is the big draw that comes after the glow plugs when starting.  If you haven't put a relay on that then all the load is going through the key. 

That is all I can come up with for now.  Check and see.

 

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