Which injector washers?

[hsmith]

This is a customer's '93 auto. Misses cold and smokes blue gray for maybe 30 seconds, then clears up and runs fine. No hesitation on cold start at all. I sent injectors and pump in for repairs as the pump was leaking. Still does the same thing. The thick washers were in place when I removed the injectors, so I reinstalled the same. Are these the correct ones for this app, and can the wrong ones cause this problem? On my '96 215 the thin ones (don't reacall the thickness of them) are the correct ones. Not sure about this application, as has been worked on before.

Thanks in advance, Smitty

 

[dpuckett]

93s have the . 090 (super thick) washers for stock, and if all else is stock (injectors and head gasket), they are the best in my experience. The washers wont help or hurt MPGs, but will affect smoke greatly.



Double check the static timing, and make sure it is between stock and 1. 5mm @ TDC (I prefer 1. 4-1. 5, but that also depends on what the injectors were set to). Verify the accuracy of the timing pin by using an alternative method to find #1 TDC. lining up the marks doesnt always mean timing is set right. Same for using the timing pin. It is fine as a guide for adjusting valves, but I wouldnt trust it without verifying its accuracy.



After that, check your KSB for proper function and power supply. There is a thermo switch on top of the intake manifold that can go bad. It has 2 black wires going to it. The switch is energized by the fuel shut off solenoid, then if the air is below a certain temp, the switch closes and feeds the KSB solenoid.



My money is on the switch or KSB. My pickup did the exact same thing when I first bought it. After about 5mi down the road, all was well.



Daniel

 

[hsmith]

Thanks Daniel, I think you have me headed in the right direction. I used the thickest washers and put the pump back as close as I could to where it was. Don't know how to check the static on these, as I am more familiar with the P pumps, and have the timing tools for it. I will check the temp switch you are talking about tomorrow. This truck acts just like you said, after a few minutes of running it smooths out and is fine. KSB was checked by the rebuilder and said it was good.

Thanks again, Smitty

 

[Don Tanklage]

daniel, how do the washers affect the smoke?



(what does a thinner washer do, more or less smoke?)



don



ps - on the ksb, remember that there are two types and that they work the opposite of ea other. i dont know how a stock truck would be effected by a non functioning ksb but on a truck with injectors the ksb hardly makes any difference. hope that helps

 

[hsmith]

So does the KSB retard timing till the engine warms a bit? Is it energized when cold or warm? Maybe I will try with it disconnected cold to see how it runs. Still need to check that temp sensor also.

Smitty

 

[NIsaacs]

The thickness of the injector washers change the spray angle. Different injectors use different angles and use different thickness washers to adjust the spray pattern.



The KSB advances the timing when cold. The next time you start it cold, remove the wire from the KSB and energize it with a known hot wire. Like Daniel said, it is probably the intake air temperature sensor. It looks simular to the oil pressure sending unit and is in the top of the intake manifold near the middle.





"NICK"

 

[Don Tanklage]

how would a different washer change the angle of the nozzle? i believe the thickness determines where the inj is in relation to the piston. could be wrong tho...



there are two different style ksb's - they work opposite of ea other. you ought to follow the wires back on your customers and figure out which style you have. on my '92 the temp sensor is not near the middle, it is towards the rear. it does not look like a pressure sensor but is larger than those usually are. it looks like a chevy h20 temp sensor, but has a 3 wire plug. there is a pressure sensor there too, forward of the temp sensor. hope this helps.



don

 

[Don Tanklage]

ps - if the ksb looks like this there is no power to it unless the motor is very cold (and power is taken away as the engine warms up)

 

[DValentine]

The piston has a bowl in the crown. The thinner washer will allow the injector to come closer to the bowl in the piston, changing the point the spray hit the piston. The bowl promotes turbulance of the injected diesel.

 

[hsmith]

Thanks Daniel, I had no power to the KSB, but the temp sensor had power, I think it is fed off the shutdown solenoid. Jumpered the connector at the sensor, and it runs smooth with little smoke when cold. Have a new sensor coming. BTW, the grids are not working either, but am not worried about that now. Looks like the relays are controlled by the pcm, as I can ground them and they work.

Smitty

 

[dpuckett]

Ok to clear the confusion. Don is right about the injector washers. They dont change the spray angle, proper, but rather placement in the combustion chamber. Moving it up and down (and side to side a little, as they are not vertical in the head, and moving them up also moves them out, and vice versa) changes where the fuel meets the air charge. For stock IC trucks with stock sticks, the thick washers were used, at least in my observations. The non IC trucks used the middle washers- . 060".



The timing is checked similar to how it is done with a P-pump, only you pull the plug from between the injector lines (as opposed to #1 delivery valve), and stick your gauge in there. turn the engine to about 45deg BTDC #1. Rotate the engine around to #1TDC, and see how much lift you get. Stock is 1. 25mm, +/- . 02mm (I think; could be as much as . 05mm). YOU DONT NEED A METRIC GAUGE. SIMPLY MULTIPLY THE INCHES BY 25. 4 TO CONVERT TO MILLIMETERS.



Look around on here to find where to get grid heater relays, if that is the problem. It will start without grids and without the KSB in 5 below weather, BTDT in mine the week after I got it. Neighbors weren't thrilled, but I got it running.



DP