2006 DT466 losing prime

[Idaho Mike]

I'm not to concerned about it, I'm sure it's because of a few things thats going on...

 

[Mr P]

I'm no mechanic, but White/blueish smoke means oil is there a

Most likely means unburned diesel, when the smoke comes from a diesel exhaust pipe.

Did you know a diesel can burn engine oil instead of diesel, and will not smoke* when doing so? You can pour engine oil, kerosene, JetA, hydraulic oil, automatic trans fluid...into your fuel tank and the engine won't hardly notice. It will cold start harder with "thicker" fuels, and the "thinner" won't lube as well.

*some smoke might be noticeable, especially in cool weather, low engine load.

Alternatively, a diesel fueled with pure diesel can smoke by injecting diesel into a cold cylinder with no glow plug or an injector "dribbling" (leaking) into the cylinder during the exhaust stroke.

 

[ewo1]

Did you know a diesel can burn engine oil instead of diesel, and will not smoke* when doing so? You can pour engine oil, kerosene, JetA, hydraulic oil, automatic trans fluid...into your fuel tank and the engine won't hardly notice. It will cold start harder with "thicker" fuels, and the "thinner" won't lube as well.

All this is so true but not the golden rule. Mechanical diesels, all day long!
Newer diesels like a 6.7 ford, no way jose!

Newer fuel pumps have such tight tolerances that any amount of "contamination" is the beginning of the end for that pump.

I had a truck that got water mixed in the fuel, from the gas station, lasted 1/4 mile down the road before she died, $12 grand in new pump repairs.
I say this so newbies don't get over confident in thinking that ALL diesels can do this!

 

[ewo1]

I'm no mechanic, but White/blueish smoke means oil is there as well which is why I believe EWO1 mentioned the injector rings being worn as a possibility. Dark smoke means too much fuel. My bus has had the white/blue'ish smoke happen on rare occasion but it's rare when it occurs, then seems to heal itself and never occur again for 9 months and tends to only happen when it's cold, never in the summer time. I don't know why it happens in winter, maybe the metal is contracting and allows oil through?

The leaking o-rings on the injector "oil input", not the injector body o-rings, when they are going bad will cause a very slow buildup of HPOP oil pressure to the injectors causing a long, long crank.

This oil that bleeds/leaks out of the o-rings goes right back to the oil pan and not into the cylinders so this oil has no chance of "burning", hence no smoke.

The blue/white smoke coming out of the pipe when cranking/starting an ice cold engine is a result of, "cold a$$ weather" as the "burn" temperature is just not there.

Once she starts and get to operating temp, that is when you need to look at the smoke and decide as to what is coming out of the tail pipe.

All ice cold diesel motors will belch white/blue smoke for a second or two.
Big diesels that is, not necessarily small diesels like my Durmax for example.

 

[Mr P]

EWO, I don't view petroleum products as "contamination". I would, like you, advise against "alternative fuels" in newer diesels. However, the "smoke" diagnostics would remain the same.

An engine that has a L O N G crank time and then belches a large amount of very light colored smoke indicates that the engine was getting fuel for some time before it "fired" (began to run).

 

[Idaho Mike]

ended up pulling the canister so I could get to the backflow. Looks like the oring had a small nick in it from something so I'll replace it, clean it all up and give it a try. That pesky, PITA pressure valve at the bottom of the canister is another culprit, all it takes is a microscopic pos and out goes the fuel back in the tank..

 

[Idaho Mike]

well, got it all put back together, primed it up and it fired up within 7 seconds. It still pulsated till it got warmed up. The true test will be tomorrow morning if it needs to be primed. Fingers crossed...
Now, I took out the pressure relief valve in the bottom of the canister, cleaned it off real good then blew into te top part of it and held the pressure, it did not hold pressure could feel the pressure real slowly decreasing. I spun it around then blew into the bottom end, same thing, started to real slowly lose pressure. I put the valve in the vise top up then put a drop of fuel in the depression where the bb is and sure enough it started to drip real slow, eventually the fuel dripped out. So, this could have been both the pressure valve and the nick in the backflow oring, either way tomorrow will tell. Fingers still crossed..
I'm trying to sell the rig this is why I'm trying so hard to make it run correctly. I will not sell marginal running rig, would not like that to happen to me..
We bought this in Florida to move my 93 year old folks back home here in Idaho with the intention of selling it when we got here. The truck had a whole front end done to it, over 8 grand worth of work, new rims, tires, rod ends, drag links bearings etc. got it for less than 3 grand, I have maybe 2 grand into it minus my time getting it to run correctly... I feel I'm still ahead of the game...

 

[ewo1]

You should replace them, they shouldn't cost too much....

 

[ewo1]

We bought this in Florida to move my 93 year old folks back home here in Idaho with the intention of selling it when we got here.

Kudos and 5 stars to you for going all out and taking such good care of your 93 y/o parents, looks like they raised you right!

 

[Idaho Mike]

if you're talking about replacing the check valve in the bottom of the cannister, those little gems are about 100 bux

 

[Idaho Mike]

just went out and checked that it held pressure, seems to have held and it fired right up, YEAH, for now anyway...

 

[Mr P]

Good job.

About what is the temp, what is crank time?

 

[Idaho Mike]

unfortunately, the temp is in the low 50's now at night, so I'll have to wait till maybe next week when it cools off, typical Idaho weather. It only took a few cranks and it fired right up..

 

[Mr P]

Is that 2 seconds, 5 seconds? I'm just curious what is "normal" for the dt466E.

 

[ewo1]

Is that 2 seconds, 5 seconds? I'm just curious what is "normal" for the dt466E.

From all the research I have conducted so far, pre 2004, 2 seconds max.
EPA/EGR, 2004-2007 known for longer cranks. 4+ seconds or more...

 

[Idaho Mike]

mines an 06

 

[ewo1]

Once source of info...

Extened crank times, 05 DT466E - School Bus Fleet Magazine Forums

Subject: Cold Weather Start ability Guidelines for 2004 Emission DT 466 Engines
Engine Family: DT 466
DESCRIPTION
In order to meet the 2004 EPA emission regulations many changes to all makes of diesel engines had to be
made. These changes were various and included EGR valves, combustion chamber changes as well as
others. As a result of these changes the engines do not start as well in cold weather. These characteristics
are common with all diesel engines and require manufacturers to approach cold engine starting differently
than in the past.

The following guidelines will result in superior cold weather starting.
SERVICE PROCEDURE
NOTE – It is normal for cranking time to be longer on 2004 DT 466 engines than previous models if not
equipped with grid heater and/or block heater.
NOTE – During cranking do not disengage the starter until the engine has reached 500 RPM.
NOTE – Ensure the engine ECM is at calibration level PL01 or higher

It goes on to list the recommendations at various temps, the zero and below recs are: 5W-40 motor oil and grid, block and oil pan heaters

 

[Mr P]

Good ole EPA.....making engines less reliable since the '70s. My dt466 Ppump starts in about 1 stroke, at 50F. That's quick enough that my daughter rode the starter after the engine was running 'cause she's used to starting her gas burning Toyota.

 

[Idaho Mike]

UPDATE: after thinking I had solved the problem now another has reared its ugliness.
After starting it up which it does great at it will only run for about 2-3 minutes then die likes it's running out of fuel. The perplexing part is there's fuel pressure at the schrader and the bleeder valve at the top of the filter canister cap. I must have done something when I pulled the cannister, cleaned it all out and replaced a couple o-rings, which by the way, it is still leaking out AGAIN, I checked it this morning and fuel had drained out of the cannister, ARRRRR.. I'm getting so friggin tired of this truck, just want to get it running and sold..