piper184
Platinum Member
Ah, that is typically called the rack. The governor runs the rack back and forth to regulate fuel flow to the injectors. When you pull the shut off it over rides the governor and moves the rack so far that all fuel to the injectors is cut off and the engine dies.
I have never had that cover off to see what was inside so I am a little confused on what is in there. Bob Rooks has WAY more knowledge than I in this area. I am having a hard time figuring out how any crud can get in there.
Is the chamber under that cover usually full of fuel? I don't know if this is normal or not.
At the very least all fuel in the injection pump should have passed through the sediment bowl, lift pump and secondary spin on filter before reaching the pump.
You do have a secondary spin of filter, don't you? When was the last time you changed it? I am not aware of a fuel filter that has a by-pass relief like some oil filters do, but that would seem just wrong. Is it possible the fuel filter is "wrong" or defective?
What you could do is shut off the fuel and thoroughly clean the sediment bowl and screen. Then remove the spin on filter and rig up something under the filter housing to catch fuel. Make sure the container is clean. Use the hand primer pump to pump fuel into that container and inspect the contents for crud. Once you know you are getting clean fuel through to that point, screw on a new filter.
My position on how to replace a filter is controversial on this site but it is the way Caterpillar mechanics are trained, so here goes.
1. Wipe the area completely clean prior to removing the old filter. Compressed air and rags.
2. Have new filter ready to go but leave the cover on the base until the last minute.
3. Remove old filter and carefully set aside. Use clean rags and wipe the area again.
4. Remover cover from new filter and carefully screw on and tighten properly. DO NOT attempt to pre-fill the filter with fuel as you will be pouring un-filtered fuel into the engine side of the filter material.
5. Use primer pump to fill the filter and remove air by using the bleeder screw. This assures only clean, filtered fuel can get to the injection pump.
Now granted, this procedure is for much tighter tolerance systems than we have, but it seems like a valid procedure to me. Flame suit on. Your tractor, maintain it the way you see fit.
Once you have clean fuel to the pump it should start and run just fine. If there are any microbes in the fuel the biocide treatment should get them. If you are not seeing water in the sediment bowl that shouldn't be an issue.
If you had problems in the past and the crud you are finding is the dead bugs, then they need to be cleaned out. Personally I would fix up some kind of a spray wand made out of some soft copper tubing and connect it to a "suck gun". Then I could bend it into a shape that would allow me to squirt fuel all the way around inside the tank. I probably would remove the sediment bowl first and fix up a drain hose to run into a bucket. If you use a funnel with a fine mesh screen or a rag or something to screen out the big stuff, you can recycle that fuel until you have gotten all the crud out you can.
Then with some fresh fuel give one more spray rinse. I have an el-cheapo Harbor Freight brake bleeder and I would fashion up a copper tube to fit that so I could go around the bottom of the tank and vacuum up the bottom as best I could. occasionally pouring in some fresh fuel. Inspect the contents in the bleeder, rinse and repeat until you have gotten as much crud out as you can. Anything left should be easily taken care of by the sediment bowl and secondary filter.
I really don't understand how crud from the tank can get all the way to the rack in the IP. Bob?
The mods I mentioned for the instrument cluster and hood hinges make life so much easier in future. I wish I had done them when I assembled the tractor. Experience is a great teacher.
I have never had that cover off to see what was inside so I am a little confused on what is in there. Bob Rooks has WAY more knowledge than I in this area. I am having a hard time figuring out how any crud can get in there.
Is the chamber under that cover usually full of fuel? I don't know if this is normal or not.
At the very least all fuel in the injection pump should have passed through the sediment bowl, lift pump and secondary spin on filter before reaching the pump.
You do have a secondary spin of filter, don't you? When was the last time you changed it? I am not aware of a fuel filter that has a by-pass relief like some oil filters do, but that would seem just wrong. Is it possible the fuel filter is "wrong" or defective?
What you could do is shut off the fuel and thoroughly clean the sediment bowl and screen. Then remove the spin on filter and rig up something under the filter housing to catch fuel. Make sure the container is clean. Use the hand primer pump to pump fuel into that container and inspect the contents for crud. Once you know you are getting clean fuel through to that point, screw on a new filter.
My position on how to replace a filter is controversial on this site but it is the way Caterpillar mechanics are trained, so here goes.
1. Wipe the area completely clean prior to removing the old filter. Compressed air and rags.
2. Have new filter ready to go but leave the cover on the base until the last minute.
3. Remove old filter and carefully set aside. Use clean rags and wipe the area again.
4. Remover cover from new filter and carefully screw on and tighten properly. DO NOT attempt to pre-fill the filter with fuel as you will be pouring un-filtered fuel into the engine side of the filter material.
5. Use primer pump to fill the filter and remove air by using the bleeder screw. This assures only clean, filtered fuel can get to the injection pump.
Now granted, this procedure is for much tighter tolerance systems than we have, but it seems like a valid procedure to me. Flame suit on. Your tractor, maintain it the way you see fit.
Once you have clean fuel to the pump it should start and run just fine. If there are any microbes in the fuel the biocide treatment should get them. If you are not seeing water in the sediment bowl that shouldn't be an issue.
If you had problems in the past and the crud you are finding is the dead bugs, then they need to be cleaned out. Personally I would fix up some kind of a spray wand made out of some soft copper tubing and connect it to a "suck gun". Then I could bend it into a shape that would allow me to squirt fuel all the way around inside the tank. I probably would remove the sediment bowl first and fix up a drain hose to run into a bucket. If you use a funnel with a fine mesh screen or a rag or something to screen out the big stuff, you can recycle that fuel until you have gotten all the crud out you can.
Then with some fresh fuel give one more spray rinse. I have an el-cheapo Harbor Freight brake bleeder and I would fashion up a copper tube to fit that so I could go around the bottom of the tank and vacuum up the bottom as best I could. occasionally pouring in some fresh fuel. Inspect the contents in the bleeder, rinse and repeat until you have gotten as much crud out as you can. Anything left should be easily taken care of by the sediment bowl and secondary filter.
I really don't understand how crud from the tank can get all the way to the rack in the IP. Bob?
The mods I mentioned for the instrument cluster and hood hinges make life so much easier in future. I wish I had done them when I assembled the tractor. Experience is a great teacher.