no start (with a twist)

[damac]

You didn't run wvo did you?

What do you guys think of startron?  I used it on an old truck and the jetta a ways back because my wvo experiment starting pulling gunk off the tank walls, etc.   That was a nightmare but a couple new filters and a tanks of fuel to a bottle of startron seemed to do its job.

[ORCoaster]

From here:  http://www.diesel-fuels.com/

Contaminant build up resulting from excessive microbial growth and bio-degradation of diesel fuel can cause fuel filter plugging. Micro-organisms, bacteria and enzyme activity, fungus, yeast and mold cause diesel fuel degradation and the formation of waste products. The process is similar to milk turning into cottage cheese, a different form of milk. Of all the microbial debris and waste products in the diesel fuel tank only about .01% is "bugs". Even though microbes may cause and accelerate the process of fuel degradation, it should be clear that the waste products clogging your filter are not the microbes but fuel components which have formed solids.

Frequently, the application of a biocide aggravates the situation and turns bio-film into solids, creating a real fuel filter nightmare. Bio film develops throughout the entire diesel fuel system. It grows in the water-fuel interface and on the walls, baffles, and bottoms of fuel storage tanks. An unlucky end user may be filling up his fuel tank and getting this debris delivered as a part of his diesel fuel, for the same price as the diesel fuel.


I knew that there were microbes out there that eat diesel and other hydrocarbons I just never thought about them being in our tanks.  Talk about loosing miles per gallon.  Maybe we should all be thinking about this more as a problem when folks tell us they can't get the car running well after it was sitting for an extended amount of time.  They make biocides that kill this stuff but then you really better be changing filters often as it will float out as a solid later.

Just one more thing learned on this novel forum. 

[BK75]

This is quickly becoming a thread jack.

I appreciate all the responses.    I checked the tank screen today; all clear.   

I thought we were on to something with that since it would seem tank level related.   I agree with the suggestions of air in the lines I just can't ID where it is coming from.   And of course the purplexing oddity of it only occuring when the tank is partially empty is really wierding me out.   There are no bubbles during operation or when sitting, until the half empty issue starts.   Then I can't tell where.   I've tried to watch it for awhile after shutting it off and don't see anything, then come back ~5-8 hrs later and the clear line is empty.

Doesn't the tank level relationship to the symptom rule out anything pump/injector/engine side as being leak source? 

Oh to the question of the relationship to the pump rebuild.   The pump was rebuilt about 14 mo ago and this issue started just a month ago.   I'm not sure where you were going with that but I will run every suggestion through.   It always seems to be my "that can't possibly be it" mentality that winds up biting me in the ass. 

[R.O.R-2.0]

This is quickly becoming a thread jack.

I appreciate all the responses.    I checked the tank screen today; all clear.   

I thought we were on to something with that since it would seem tank level related.   I agree with the suggestions of air in the lines I just can't ID where it is coming from.   And of course the purplexing oddity of it only occuring when the tank is partially empty is really wierding me out.   There are no bubbles during operation or when sitting, until the half empty issue starts.   Then I can't tell where.   I've tried to watch it for awhile after shutting it off and don't see anything, then come back ~5-8 hrs later and the clear line is empty.

Doesn't the tank level relationship to the symptom rule out anything pump/injector/engine side as being leak source? 

Oh to the question of the relationship to the pump rebuild.   The pump was rebuilt about 14 mo ago and this issue started just a month ago.   I'm not sure where you were going with that but I will run every suggestion through.   It always seems to be my "that can't possibly be it" mentality that winds up biting me in the ass. 

its only a thread jack when it has NOTHING to do with the original thread..

the algae in diesel is a GOOD reason to cause a no-start condition.. i faught algae all summer last year at the resort in alaska.. would have to change fuel filters every few days, on 30 boats.. so i was pretty busy..

if your pump was rebuilt 14 months ago, i would make sure its not a feed line restriction, then i would bring it back to the builder.. if he didnt fix it , i would then kindly throw it thru his front window..

[CRSMP5]

ok screen clear.. that sa good thing...

next... how old is fuel filter? we know its diesel sucking issue.. just need to figure out where its got issues..

[burn_your_money]

Maybe your fuel pickup or return in the tank has a pinhole leak.

[BK75]

Wasn't able to get back to it yesterday. 

I like the pin-hole suggestion.   That would follow the partial full symptom.   I think I can test that using my brake bleeder.   

The filter was changed a few weeks ago.   It was the first thing I tried; before I realized it was fuel level dependent.

I'll be certain to post what I find next.

[regcheeseman]

Is it not just a leak in the delivery hoses?

I'd be digging out my diesel diagnosis bottle....


Remove the lines from the filter and immerse them in a bottle half full of diesel.

Run the car, turn it off for the time that it takes for the problem to manifest and try to restart.

If the problem is still present then you can discount the tank, lines and filter from your enquiries!

I had the factory crimp on the join between clear and black hose leak - took me an age to find, simply because I assumed the fault couldn't possibly be there.

[BK75]

I think I found it this weekend.   Trying to pressurize the line backward from the firewall a bunch of crud (don't have any idea what) came out of the line.   I haven't had a chance to drive it successively under half tank to prove it out but it seems like the likely culprit.


Thanks again for all the helpful suggestions.   The pinhole in the fuel line suggestion was what prompted the discovery.   

Now back to my lurking.

[ORCoaster]

So this "crud" was keeping fuel from returning to the tank?  Did you capture the crud in a jar or bottle or fish it out of the tank itself?

[BK75]

The crud came out of the supply line, I guess I should have checked the return line as well.   I removed it by syphoning it out with the fuel like a vaccum through the access port.   It looked like dense fuzz, like the hair balls that form on the bottom of a pool. 

[92EcoDiesel Jetta]

What consistecy and color is it?

[ORCoaster]

Probably soft and gray.  Aren't all hairballs like that?  My guess would be black and like packed lint out of a dryer.  I am using his Crud word as my basis.