Finally, something to give back!!!!
So I have a 3208. I gotta keep this quick, since I'm on the clock.
I guess from running too much bio, and too little fuel through my truck overall during too long of a time period, I apparently picked up too much moisture in my fuel.
This caused my IP to stick closed. I mean, fuel shutoff solenoid was no help.... since the lever that the solenoid actuates was stuck closed (which is what I deduced - read on).
Back to my "learning moment". When my truck didn't run last year, I noticed it was a fuel issue. So, I replaced all of the fuel lines from the lift pump to the IP. Still, no love. New fuel filter, topped off and primed. Zero. I then thought of the solenoid.
Inside the IP (again, this is what I learned later on in my activities), there is a lever that naturally slides on a chromed rod with each rotation of the compressor (I think of the IP as a mini-engine-in-reverse, which is what it looks like when you take the cover off). The solenoid, which needs a 12v feed AS WELL AS a good ground connection to the terminal (grounding the case is not enough), naturally pushes down on this lever to stop the flow of fuel (spring loaded). When energized, the dowel is sucked into the body, allowing (IIRC) the next revolution of the engine to push that fuel-stop mechanism vertically up, allowing fuel to flow.
This means that you can remove the solenoid to get the engine to run... in theory. When I removed the solenoid and tried to get the engine to crank, the only concern is that under any sort of runaway condition, you'd be lucky to make it to a bunker before the shrapnel hit. That's conjecture (and perhaps a bit melodramatic, honestly), but I don't like to be without a failsafe, and removing that solenoid and running the engine (with or without governor, that just reminds me of a gun "safety") felt a bit sketchy to me to be trying this.
Still, my runaway engine concerns notwithstanding, I removed the solenoid. And yet, still, no firing.
This is when, upon closer inspection, I realized that the fuel lever, underneath the solenoid dowel, was not moving up. Or if it was, it wasn't taking the rest of the works with it... I could sort of feel a lack of movement, like, even though I could pull the lever up from the hole created by the missing solenoid, it wasn't really *doing* anything. Sort of like a locked car door handle will move by itself, but you know it's not engaging the door opening mechanism.
I figured, the only way to get the truck to move, at that point, was to remove everything from the top of the IP, pull the top cover, and figure out what's not moving inside. Upon doing so, I was able to manually cycle the little wishbone-like lever system that allows fuel to flow. This mechanism is just in the aft side of the IP, and on mine, was stuck, with very slight but noticeable gumming on the interior machined/chrome surfaces of the IP, and corrosion on the cast iron items. By cycling it this mechanism by hand, I unstuck the IP enough to get fuel to flow.
I have since talked to an old Cat service/salesguy, who mentioned that, and I quote, "If you spit on the ground next to a fuel tank on Cat 3208, you need to run a water seperator." Well, I essentially run TWO, and I still had issues... I think this was because of my use of Bio, which basically entrains water into the mix.
Anyway, getting back to my truck, I sometimes notice that this mechanism retains its stickiness. I have a remedy - I will place a 12" long wood block on the cover of the IP, and with the fuel solenoid energized, rap on the wood lightly with a hammer or a rock. Whenever I do it, it looks terrible, but doing this tends to work.
I hope this helps,
Last edited by Trango; 04-29-2008 at 05:29 PM.