1937 RD4 Cat, no fuel into D4400 engine, throttle bad?

Rack could be stuck in the fuel shutoff position. But, you should still get fuel out of the injector line when the engine is cranking over. There is a bleed screw behind each injector line on the top of each pump. Might have to make a socket to loosen them, they're hard to get a wrench on. I think someone said a 5/16 1/4 drive socket can be flattened a little in a vise and fit over the heads.

CC,
Thanks for the reply!

I'll look for your bleed screws.
Sounds like they're after the injector pumps, doesn't unscrewing the line from the top of the injector pump do the same thing?
No bleed screw between filter tower and injector pumps?

I have no idea how this throttle rack thing works or exactly where it might be stuck.
Guess I'll pull that inspection plate again and spray the heck out of it with WD40.

Raining now, might be a few days before I get back to it.

Jerry

As already said you must bleed every pump before fuel will flow, so undoing the fuel lines will do little if the pumps are not bleed first! Regards Andrew

Sometimes pumps will bleed out if the line is loosened, but not always due to the spring loaded check valve inside of each pump. Rack could be stuck due to one pump in the up position. Take side plate off off side of pump housing, turn engine over with starting engine and observe the pump plungers and see if each pump is moving up and down. If not, gently try and move the rack each way until pump frees up or pry that pump down. Bill Walter

Those bleed valves are on the inlet side of the injection pumps, so they should bleed air out and fuel right through to the pumps, sounds to me that the rack is jammed shut, as has already been said, look through the side at the pumps with the engine turning over, one pump is probably not moving, if they do all go up and down, try moving the rack back and forth with a screwdriver.

With the throttle set into the stop position, fuel will come out of all the fuel injector lines at the pump or at the injectors, if the lines are undone at the injectors the air will be expelled and fuel will come through, there is no need to undo the pump vent valves if you don't have the bleed key, I hardly ever bother with these bleed valves, anyhow it sounds like you have a stuck pump plunger element causing the fuel rack to not move, take off the cover plate and look for the plunger that is stuck, spray some WD40 type jollop at the components and realize that you need to hook the element free from above the rack control downwards only, take some time to make a bent rod or screwdriver to manage the task, don't be going in there with anything looking like a hammer as things break off, you need the spring tension only to bring the plunger back on to the cam.

tctractors

p.s. your fault will not be with the rack or control, it is with the fuel pump element.

Agreed TC, I always used to bleed fuel systems the same way as you with the governor fully closed, and just open the injector lines, but as you know, if the filters have been changed and all fuel drained down, its more difficult to get the air in the system past the non -return valves, and if he has a tank full of fuel, he only has to go for a cup of coffee and leave the bleeders open and the system will bleed itself up to the pumps while he is away.
This is the old type machine with the governor in the front timing case, I'm not sure if the linkage can seize at any point as it goes right through the fuel injection pump to the control and spring on the back of the pump.

The early style governor/injector arrangement still has a couple of bushings where the rod goes through the fuel pump that can also stick. Also take the side cover off the governor and see that the slide mechanism is free.

Stopped raining, I went out and poked at it some more. And then thought about it.

From my first post:
"Moving throttle from shut-off to full on, it stretches the spring but nothing else moves. Plate with slot is always positioned fully to the rear, seems that should be full on throttle, perhaps the governer is involved here? Can push the slotted plate forward a quarter of the way up through the slot, but it springs back to place. How is this throttle supposed to work?"

I think that even with the operator's throttle control lever in the fuel cut-off position, a stopped engine has the throttle rack fully to the rear, in the full throttle position. I can push the rack to the front with one finger, it travels smoothly for one and 3/8 inches before hitting a firm stop. When the operator opens to full throttle, the spring gets put under tension and it is much more difficult to push the rack forward. My best guess is that all is well, and that with the engine running at idle the governor will pull the rack fully forward when the operator's throttle control is at cut-off. The slot is about 4" long not because the rack has to travel that far, but mostly because the operator control needs that much room to tension the spring.

Sequence of events here was as follows. I think. Some rust on the sides of the fuel tank from years of condensation, a bit of that crud got into the transfer pump relief valve and held it open, so no pressure at the fuel gauge. We saw no fuel and changed the fuel filters, but didn't realize there were bleed valves behind the injector pumps that needed attention. When we eventually got fuel through the filter tower but not out of the injector pumps, started wondering if the throttle was at fault.

I could be wrong about how that throttle works. Any opinions? Anyways, couldn't get the pony motor going today. Carb trouble, mostly. But I'd like to think that if the pony ran, I would have gotten the diesel going.

Jerry