Just because someone can change out the parts on a vehicle does not qualify them to be a mechanic, anymore than a "sanitation engineer" has anything to do with engineering. Unless a "Mechanic" understands the physics behind the operation of an engine then they are just parts changers.
tjkj2002 wrote:
Fuel,be it gas or diesel,is more dense the colder it is,just like cooler air helps make more power in your turbo diesels.
For every 100F rise in diesel temp past 0 degrees F the volume expansion is ~0.0432, so for a fuel temp of 200f the increase in volume is 0.086% however because the common rail system does not have positive displacement injection events you also have to factor in viscosity. At 210F, the viscosity of diesel is 1.3 cSt. At 0 F, it's 28 cSt, that is nearly 20 times thinner at 200F than at 0F. That is one of the reasons that the computer has to decrease the pulse width of the injection events with increased temperature. If you disable the temperature sensor (unplug it) the computer will think that the fuel is ice cold and lengthen the pulse thus increasing power, but also EGT. The thinner hot fuel also atomizes better as well which also increases power burn temp. The increase in torque and HP that you see on a dyno in cold weather has NOTHINGto do with the fuel, it is a result of the much denser charge air going into the engine.
tjkj2002 wrote:
Why your CRD is just a over-glorified gas engine,bet you didn't know that,all light/medium duty so called diesels are just a gas hybrid engine.Like I said TRUE diesels do not need glowplugs,they use 100% cylinder heat to combust fuel/air mix,even at startup.You can thank GM.
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Are you kidding me? Do you know of a gasser with wet sleeves? Perhaps you could make us aware of a 4 cylinder gas engine or even a V8 which has main bearings the size of the ones in the little VM Motori, . Maybe you know of a gas engine which can run a compression ratio of 17.5 to 1? Do you perchance know of any gas engine which makes nearly double the torque to HP? The fact is that the VM Motori was designed from the ground up as a diesel engine, but you would already know that being a "Diesel Mechanic" wouldn't you?
tjkj2002 wrote:
I've worked on many diesels that do not need,nor have any,glowplugs and they start just fine,even at -30 degrees
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tjkj2002 wrote:
Yay most of those tactical trucks do have cold start kits but how many do you actually see with the ether bottle or known how to use it?That was the first thing we did as mechanics was to take any ether bottle off so the idiot drivers wouldn't turn there trucks into bottle babies.When I was in the Marines all the big trucks had a ether cold start systems that we disabled,along with the deep water fording kits(except for HMMWV's).The LVS(MK48) had the Detriot 8V92TA like the Hemitt but also had a ether cold start which was also disabled,2 strokes and ether don't mix very well,it would always blow the head gaskets.The newer LMTV's and FMTV's use a automatic ether cold start sytem which is computer controlled,it will inject ether at will since the military's switch to JP8 fuel.The older M800 series manual 5-tons(cummins 240's) used one single glow plug in the intake with a nozzle pointed at it that sparyed ether,great way to blow apart the aluminum intakes,we had to disable all of those since those intakes aren't cheap.All of those vehicles started just fine below freezing with no starting aids,sure a few cranks but not really longer then when it was warm out.Now the HMMWV uses glowplugs,there just lucky to start,period.
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Well get it straight, first you say that TRUE Diesels don't have or need cold start assistance then you state that you disabled the cold start features on the above mentioned vehicles. Obviously they had them and the manufacturers thought that they needed assistance.
Diesel envy causes people to spout off and put down the usefulness of diesel vehicles but for some reason they are always lurking around the diesel forum.
As to 3camps question, You are not likely to see the fuel temp climb very high in your part of the country but it can happen, If you were to try unplugging the fuel temp sensor or putting a resistor on it, make sure that you add some two stroke oil for lubrication of the IP. That is the main reason that the computer causes a limp mode at ~168
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We know they have insulation around the battery to keep it cool. So how about wrapping the fuel filter to insulate it from engine bay heat 
What do you all think?
