John Deere 4600 injection pump gummed up

tbrooks26 · Oct 5, 2015

Hey everyone. Finally got some time to work on the JD. I've got the new range shifter rod in, and everything back together enough to run it. I have 2 issues right now. The first I noticed was the light for the glow plugs is not coming on. I looked and searched through the manual for glow plugs, but I can't find anything. It will run with some ether, but I don't think that means the plugs are working. The second main issue is fuel is not going through the injection pump. Now this tractor has been sitting for 5 years, so I'm hoping its just gummed up. I flushed and cleaned the fuel tank, filter, and bowl. I have good clean fuel at the inlet to the pump. I removed the fuel return/bleed line from the filter, and pumped and pumped the mechanical fuel pump lever. I got like one air bubble from the injection pump bleed line, but fuel keeps coming out of the nipple on the fuel filter where the line connects, and I didn't have a cap, so I was making a mess and stopped that. I have removed all the lines from the top of the injection pump, and have nothing there. The manual says these pumps are supposed to be self bleeding, but I may need to do more to help it along. It may even be the internal fuel shutoff. I tested the solenoid and it is definitely working, but I couldn't feel much movement on the lever it pushes. I saw someone on a different tractor removed the side cover on the injection pump, to free the internal shut-off, but not sure if mine is the same. As of now, I blew the fuel out of the pump, and slowly filled it with as much carb cleaner as I could, and have left it to sit for a little while, to hope it breaks things up some. Another issue coming later, is the clutch is frozen, but I've read many threads on that so hopefully that will be an easy fix.

tbrooks26 · Oct 9, 2015

Well I can't get to anything through the covers on the pump. I've tried lots of things, and not making any progress, but I have learned quite a bit. Tomorrow I'm going to remove the delivery valves off of the pump and check them, and fill it up with some carb cleaner. I'm thinking it is probably either shut-off or check valve related. I am very tempted to try and remove the governor or governor cover. I can't find any info on how or what is entailed in doing this, but I'm really hoping the cover just comes off, and parts don't go flying everywhere. Either way when I get to that point, I'll either be able to fix it, or have to take it for rebuild. Also this tractor only has 630 hours on it. I'm sure it just has to be gummed up somewhere from sitting with off-road diesel for so long. I did try today to bleed it some more, and also pulled the return line from the tank, and used my compressor to give a boost to the fuel pressure, but no luck.

tbrooks26 · Oct 10, 2015

Well I worked on the delivery valves today. When I started to loosen the first one, fuel came out of the top. So I immediately tightened it back down, and turned the engine over, but no fuel would come out. So I went ahead and took it all the way off. Luckily I didn't lose any parts lol. There's a spring and a couple other small parts, but it all looked quite clean. So I cracked loose the bolt holding the return line and watched the fuel drain down. Then I went ahead and put it back on, but left it a turn or so loose. Then I loosened the others slightly, and started to spray carb cleaner into one. To my surprise it instantly came out the other 3. So I sat there and slowly dribbled carb cleaner until it was overflowing all the other valves. Gonna let it sit a few days, see if I can find anymore info, and then get back on it.

tbrooks26 · Oct 17, 2015

Well, I have it figured out finally. The plungers in the pump were stuck. I had to remove the delivery valves, and the check valves underneath them, and then I trimmed a wooden dowel to the right size to tap the top of the plungers and break them loose. I still don't have it running yet. One of the plungers is still sticking some, so I filled it with penetrating oil, and gonna let it sit for the night. I did have penetrating oil squirting out all 4 delivery valves at 1 point. It was all pretty obvious once I took of the side cover. 3 of the springs that return the plungers to the bottom were compressed. Also the pinions that rotate the plungers wouldn't budge either. I may go ahead and get new plungers, if I can find someone who will sell them to me. They look fairly easy to change out at this point. Hopefully I'll get it up and running tomorrow!

Coyote machine · Oct 17, 2015

Carb cleaner, NOT good. You should use only penetrating oil, or similar, to free things up. You may think of carb cleaner as a de-gummer, but it's no good for a fuel injection pump. It dries things out real bad, which is the opposite of what you want as a finished condition of the IP's internal parts. Yes, it needs to be degreased, but more importantly, afterwards it needs lubricity. Use Aero-Kroil or PB Blaster to free things up.
Also, contact Conestoga diesel and ask them for assistance. They work on IPs of all types of diesels, tractors, trucks, etc.
And maybe wait long enough to allow some TBNers to reply to your thread/posts....

Texasmark · Oct 18, 2015

Sea Foam comes in an aerosol and regular pint can and sold by WM and most auto parts stores. Been around for 50 years and obviously works. It's made for 2 and 4 strokers, gas, LP, and diesels. Put it in your fuel normally, or spray the aerosol where needed. It cleans things up without tearing things up. It contains mineral oil, naptha, and alcoho. Nothing there to rip things apart like something on the order of Berryman's Chem Tool made for cleaning carbs. would. Then keep some in your fuel or go with the Power Services products for fuel maintenance.

Also for a blasting cleaner upper, I use brake parts cleaner aerosol, popular at most auto parts stores, lots of brands. It comes out at a good pressure with lots of volume, doesn't leave a residue, cleans up all sorts of things but won't cut your paint like Chem tool will and doesn't hurt rubber brake parts so obviously it won't hurt your IP.

tbrooks26 · Oct 18, 2015

Thanks for the responses guys. I quit using the cleaner, and have been using pb blaster the past few days. As to Sea foam, I've used it as an additive, but have never seen the aerosol. I threw some stuff I found at my local auto parts in with my new fuel, think it was called diesel kleen.

I worked on it a little while today, and was able to get everything moving nice and freely. After that it fired up and ran good!! Then I turned the key off, and it kept running. Remembered I left the solenoid out, stuck it back in, still running. I still had the side cover off of the IP, so I tried moving the plunger pinions by hand, they moved freely, but wouldn't kill it either. Put my hand over the breather hose, still ran lol, so I had to turn the fuel petcock and wait for it to die out. So I bolted the solenoid back in, and tried again to see if it made any difference, but it did not. It was weird though, I pulled the throttle all the way down, and then when I turned the key off, the rpms went up a little bit. I'm guessing there must be something else, maybe in the governor, that is clogged/stuck.

Texasmark · Oct 18, 2015

One of PS products is Diesel kleen. One thing it goes after is injectors. Course if you are going to clean them up the rest of the system will get cleaned too.

You talking about a key operated fuel flow solenoid valve between the fuel source and the IP? Confusing that you put it back in with the engine running.....sort of how did you do that and in doing so, how did the engine keep running?

I'd just keep the cleaners in it and give it time to clean itself up. Since you are making progress that shouldn't be all that hard for you to do, is it? Grin.

tbrooks26 · Oct 21, 2015

The solenoid mounts onto the governor of the IP. I just pushed it into the hole it mounts in, Which should have shut it down, but it did not. It did however rotate the plungers like it is supposed to, so there must be something in the governor sticking. I'd really like to get this thing going soon, but I have other projects going on so I may give it a break for a week or so. Any other time I wouldn't be too worried about it not shutting off, but my next issue to fix is the clutch being frozen, and I really don't want to try to break it free without being able to kill the engine in a timely manner.

tbrooks26 · Oct 24, 2015

Well, stopped by my JD dealer to grab a few things. Talked to a guy there, and he said there shouldn't be anything in the governor keeping the fuel on. I still think it might be in there though, how else would the rpms have gone up when I turned the key off? Maybe the solenoid isn't going out all the way? Not sure. All my free time is going into my new property the next week or so, while I have a trackhoe there, so it will be a bit before I get back to it.