BDT

the other morning i started up my pick up, the temp. was about 35 degrees and upon starting produced quite alot of white smoke and also loped like a cylinder or injector was dead, smoked until the temp came up and i hit the highway then idled ok and no smoke after that, even when i came home that evening. i did stop and refuel , i still had summer fuel in her. i haven't tried starting it since then but i will try again. any suggestions

Monty

Welcome to the site BDT. To better help you in the future. Please go to your profile and enter a little bit of info about your truck. <br>

1stGenBikeHauler

<br>I went through the same scenario the other morning with<br>my '92. It loped a bit so I just touched the gas pedal<br>to get the engine off of idle and let it warm up a couple of minutes and then dorve around real easy. I really dont think its a problem.<br><br>I have a theory as to why the 1st gen's see this more<br>than the later model trucks. Since the VE pump has a final<br>injection pressure that is lower the the later model engines,<br>the atomization is not as fine. Meaning that the fuel<br>droplets are somewhat larger AND the timing is not quite as precise as it is with the later pumps. Both things that cause higher emission levels and why the OEM decided a pump change upgrade was needed AND why we get a litte smoke at start up. My truck has 126,000 on the clock.<br><br><br>I had a suzuki samurai witha VW turbo diesel that I swapped in. GAWD that motor had some miles on it and it had a VE pump just like the one on my cummins. On cold mornings<br>it would shoot CLOOOOUUUDDS of white smoke. Im sure it<br>had other problems but once it warmed up it was fine.<br><br>Matt<br>

Monty

Sounds to me like your KSB is not getting the signal from the KSB sensor. The KSB (Cold Start Timing Advance System) raises you pressure from 4 bar to 8 bar (advances timing) to aid in cold starting. When my KSB sensor went out, I had the same symptoms. Loping, white smoke, the works. I got both the KSB sensor and the Intake Sensor to be on the safe side. Worked like a charm afterwords. The KSB sensor and Intake sensor is mounted on the intake plenum back from the intake horn. You will see a clip on connector on the top of each.

1stGenBikeHauler

<br>The KSB info is good to know. The old VW pumps have a cold start **** on the dash that advances the timing a bit, I dont think that it raises the pressure. <br><br>BDT's truck may be pumping alot of smoke. Mine just did it a tiny bit and only for aboutfive minutes. Its just something that I dont see the 98+ model truck doing. <br>

BDT

thanks for the info. tried this morning and not alot of smoke and cleared up in about 5 min. I know they change the fuel mix for winter here and that did seem to help alot. I will look into the cold start syst. thanx

yomitch

you should see my volvo generators when they start in the winter, it looks like the wicked witch of the west is coming!!!

Bushy

yomitch,

One other thing here,, if your idle is too low to start with, then when those heaters come on you'll really see a degradation in idle speed/quality. Check your idle, it should really run between 750 and 850 RPM and, I don't care what the manual says,,, trust me here. These ole girls like a tad more idle.
The KSB can be checked quit easily,,,,
Make up a wire about 2 1/2 feet long with aligator clips on both ends.
Lift hood and remove the connector to the KSB.
Clip one end of the wire you made to the KSB connection and the other end tuck out of the way for now....
Start truck, jump out and connect the other wire end to the &quot;+&quot; side of battery... if the KSB is working you'll feel/hear a difference pretty quick. You may need to listen to the engine sound and watch engine idle quality, but you should see a difference. I really notice it on mine.
If you don't see ANY difference the KSB is pooched. If you do see a difference, then the sensor may be pooched if it does not produce the same result as the wire test.
Test worked for me and two other guys just recently. It's cheap easy and quick.
One last note, if your KSB is working ok and you still get a decent amount of white/bluish smoke you should check you initial pump timing. That will cause this cold start smoke to be worse if it is set to low.


Bob.

Bushy

Hey Matt,<br><br>I'd like to kick this around a bit too.... re:&quot;...Since the VE pump has a final<br>injection pressure that is lower than the later model engines,<br>the atomization is not as fine. Meaning that the fuel<br>droplets are somewhat larger AND the timing is not quite as precise as it is with the later pumps....&quot;<br><br>On our VE's the injection pressure is determined by pop-off pressure of the injector's &quot;bar&quot; setting. If you have a 225 bar pop-off then you can compensate for a percieved lower pressure by changing the holes/diameter/spray angle.<br>This will in effect produce sufficient atomization for proper burning, even at cold idle. The quality of injector will determine droplet size/quality, assuming the pump is running within spec. of course. The rated supply pressure to injector for our VE's is approx. 8,000 psi. and a 225 bar injector will pop-off at about 3300 psi. so there should be no problem with atomization, even at idle if pump and injector are in good health.<br>As for timing, our pumps use static timing. Once set, that's it. The only time it actually advances is during KSB operation, and that is done, as mentioned above, by raising internal pressure from 4 bar to 8 bar during KSB operation.<br>After that it's back to 4 bar internal pressure. An example is the 185 Bosch or Lucas (POD) injectors. They have a higher pop-off pressure. In the case of the Lucas, it's around 250-255 bar. They are also large sac injectors and need the higher pop-off to atomize properly since they flow higher volumes of fuel.<br>All this results in retarding &quot;effective&quot; timing resulting in the need to advance the timing to compensate for the higher (and subsequently later) start of the injection cycle.<br>The introduction of higher emission standards necessitated the use of the P7100 pump/higher pressures/different nozzles/angles/holes ( I think) to keep emissions down. This was used in conjuction with variable timing via PCM/ECM or whatever they called it. <br>So my point is this I guess, if the pump is up to par and the nozzles are clean and their pop-off pressures are matched fairly well, then atomization/burning should be just fine.<br>One last item here. On our 1st Gens the injector angle in relation to the piston bowl is not the same as a newer truck. Ours fire the fuel mix at an angle towards the fuel bowl. On the new trucks the injector fires directly down into the bowl. The also makes a difference in efficient burning, even<br>pressure(s) over the entire piston head and less angular pressure variance that is seen in 1st Gens due to the angled injection.<br>What do you think? Do you see any holes in this? Anyone want to jump in and fix any errors please???<br><br>Bob.<br>

Lil Dog

I was told that the VE pump has some advance throught the speed range.. That is why you have only a 10° advance at idle instead of the P7100 pumps of 15-18°. The VE pump is supposed to have a mechanical advance to move the timing.<br><br>AS for all the white smoke.. Have the timing checked!<br>Mine was a slobbering hound when I first got it, and the timing was at 1° instead of 10.. That made the biggest difference in startup and smoke.<br><br>J-eh

Alec

The VE pump does not have static timing. The timing is adjusted based on internal pump fuel pressure. There is a vane pump directly coupled to the input shaft of the pump -- as engine speed increases, the volume of fuel pumped increases -- and a pressure relief orifice. These work together to determine the internal pressure of the pump. The internal fuel presses against a spring loaded piston which rotates the &quot;roller ring&quot; that the cam rides on, advancing and retarding the timing relative to engine speed (and load, to a slight extent. There is a version of the pump that adjusts timing more aggressively depending on load, but I don't think our pumps do this).<br><br>The KSB advancess the timing by closing off and raising the pressure in the line to the piston.<br><br>The P series pumps DO have static timing.<br><br>As engine speed increases, it is advantageous to advance the timing to compensate for the relationship between the time it takes for the injection pulse to travel from the pump to the injectors, and corresponding angle of engine rotation. As engine speed increases the line lag for the injectors is constant (in time) but corresponds to a larger angle of rotation.<br><br>I thought that the nozzles on the later model first gens were pintle type -- if the POD's are large sac that would make a big difference in smoke because there is no way to control how and when the fuel left in the sac after the delivery valve closes is burned.<br><br>Wrapped up in the pressure volume variables is of course duration, and duration has an effect on how complete the combustion is. Don M's injectors with more holes effectively allow you to have more fuel over a short duration still mix with more of the air charge before initiating combustion (for example). If you dump a whole bunch of fuel into the combustion chamber at once, only so much of it can burn so fast -- leaving some to burn with a worse air to fuel ratio, or in a higher/lower pressure environment.<br><br>On a slight tangent -- does anyone know where to find a good analyses of the &quot;polluting effects&quot; of the NOx family?

Bushy

asilitch,<br><br>Well spank my bottom and call me momma.....<br><br>If timing is advanced via internal pump pressure in relation to RPM, and the upper end pump pressure is 8000 psi, what is it at the lower end such as idle?? Is there alot of variance?<br>You are exactly right about the remaining 'doplets' of fuel in the large sac injector. That seems to be one of/the source of the &quot;haze&quot; at idle.<br>As for duration, is that a function of the pumps ability to maintain pressure during the injection cycle and the 'crispness' of the injector?<br><br>Bob.

1stGenBikeHauler

Wow has this discussion gotten deep <br><br>The timing advance characteristic of the VE pump seems<br>to be more desireable than the static timing of the<br>of the p series pump......but....<br><br> As engine speed increases the heat loss to the cylinder wall is reduced and ignition happens sooner in the compression stroke. On top of that flame propagtion speeds up since<br>the fuel air mixture is more dense and there is more turbulence in the cylinder. Both require timing adjustments.<br>With a lower pressure pump you have a longer injection<br>duration for a given amount of fuel and less time to play with during the compression stroke.<br><br><br>The higher pressure is cool and makes the P pump work. You can simply get more fuel in within smaller time constraints due to the higher pressure. This also make the engine run cleaner not only because of better atomization and a &quot;sharper&quot; pulse, but you have more time to play with and you have a better chance of getting the timing dialed in. Now that the injection pulse is shorter for the same amount of diesel now you have time to add more fuel and make more power with the P pump.<br><br>Now I have a question....what is the frame difference with the late model electronic VE pump. Can it be bolted to a 1st gen. (electronics aside)<br><br>