Hi, This info is from a friend on a Cattle Station, I have not seen the problem first hand. Under load, mostly injectors 4,5,6 getting visibly hot and leaking from top Oring. Was fine when parked, then when started a few months later it had this problem. Injectors have been replaced and screen in side nozzle appears Ok. Still does the same with new injectors. OK at idle but under load they get hot then start leaking from top seal. Any help will be much aprreciated.
I'm thinking it is a difficult thing to do. Looking at something and telling how hot it is, unless we are talking the metal turning a certain color from the heat. So your saying these injectors are turning a different color? Have they used an IR temp thingy? All injectors replaced? Are they the correct ones?
Yes Injectors are changing color, it can bee seen that they are hot. I would assume correct injectors.
Do they do this when the engine is cold? I guess not? Any other work done to the engine before this happened? So guessing after the engine gets to operating temp, then this happens? Any gases in the coolant? No rags left where they shouldn't be? Maybe others here have some idea's. Keep us posted on what you find.
If it’s been sat for a long time,are any coolers blocked or cracked?,possibly oil has settled in radiator blocking flow. This can cause restrictions up at the head and get things dangerously hot around combustion chamber seals and injector seals. You may be close to cracking heads?
It was running fine until the operator smelt fuel and checked the engine. Found the seals leaking and injectors hot. So no work done to cause it. It seems to run fine and is ok until it is put under decent load. Coolant temp is ok, not losing coolant ect. It had only been sitting for a month or two, not uncommon for Station machines. Most of the time it would not be working hard, pushing a bit of dirt or trees. It was cleaning dams so was working harder than normal.
Do you have a serial number? I'm guessing that it has a 3306, but I'm not sure of which fuel system.
Ser No: 44W0302 Eng No: 44V15652
I'm not really sure what could be causing it. I wouldn't have thought that the fuel could get hot enough to cause those sort of problems. The sleeve metering fuel pump has a constant bleed valve that returns some fuel back to the tank to cool the fuel in the pump, but it's not a huge amount. There should be a fitting on the front of the pump with a line connected that goes back to the tank. You could check that to see if there's anything coming out & how hot the fuel is.
From memory,the seals around the pc chamber are sitting in water,so can’t be that. As for the seals on the injector nozzles,I thought they were to keep dirt out really. It’s been a long time for me,but sounds like your nozzles and adapters aren’t sitting well,or slobbering nozzles
Whats the quality of the diesel , has got the bug in it .
Just a thought, Is there any circulation in the radiator
Will follow up on that. New injectors have been fitted with no change. Fuel is good. I have had "The Bug" in fuel before. I have always found it blocks filters causing low power. Coolant temp is fine so radiator appears to be ok. I have not seen inside one of these engines. Is it possible there is cooling system passage blockage around the injector area??
pretty big area around chambers
Since is was half the engine I was thinking rag or something blocking the rear, but then you say it was fine before? Like mentioned make sure the coolant is flowing not just looking good. Maybe remove and check the thermostat, and check for flow then as well. Any black smoke when under load? Lack of power?
Yes it was fine until it started this issue. Will check/recheck all the cooling system. No abnormal black smoke or lack of power.
Wouldn't the governor open up and supply the hot 3 cylinders more diesel if there was a drop in power to some extent covering for the 3 cold cylinders if there was a drop in diesel supply to them . I think the injector pump needs to be checked . Last time I had a pump worked on I was asked if I wanted the pump set with the plungers delivering even loads at moderate throttle settings or at full load. As the pump ages the plungers wear at different amounts with uneven heat between cylinders the end result . I went for the full load as I figured that is where the heat would be at the biggest difference . In my first sentence the issue could be opposite of that with low supplied injectors getting hot because of the lack of cooling coming from the diesel .
Checking the pump supply is on the list of things to do.
Another silly thought, does this tractor have a compact fuel injection pump or a sleeve metering injection pump???
I have no Idea. I will see if someone on site knows. Ser No: 44W0302 Eng No: 44V15652
Easiest way to tell there will be a big flat plate on side
I am about 7Hrs drive from the machine. Just got some to take some pics.
compact is what that is I was thinking if it was a sleeve metering rust could cause problems with the sleeves
I thought I had looked up the information for that engine serial number & found a sleeve metering pump, which is why I said to check the constant bleed valve. Since it has the compact pump, I don't know. A fuel pressure check of the transfer pump may show something.
Is the motor original , that paint suggests it may have been used in another application .
Interim scroll fuel system is correct for for 44W0295-up DI starts at 44W0441 It would take severe loss of heat transfer to the pre-com chambers to gain that much heat or exposure to combustion products??? Poor heat transfer would not show up in normal cooling system temperature water. What is the condition of the coolant being used?......no ditch water!!!!
Sorry for the slow reply, I did not get notifications. Motor has not been replaced by the current owner, so may or may be original. The system has had clean water and Antifreeze/antiboil since current owner has had the machine. Owner has been busy with cattle work. I am going out in a week or so for a while. We have 2 infrared temp guns and I have a temp gauge with an eye lug sensor wire I can bolt or clamp on. Will see if we can get some idea of what temps are happening where. Thanks to all for taking the time to reply.
Good idea with the temp guns. My guess is cooling system related hot spot.
Its going again. The machine has been pushing hard the last few days putting a track up a Basalt wall without overheating injectors. The engine oil cooler only had about 4 coolant tubes that were open. It was removed and all but one tube was able to be cleaned out. Its possible the thermostat bleed hole was blocked and the water pump had a corrosion on the impeller and a weep from the tell tale hole. So new pump, bleed hole sorted and new thermostat. Basically no coolant was circulating, so getting hot at the rear of the head. As there was no circulation, no hot coolant could get to the temp sender. It does have a small amount of fuel weeping from the large oring at the top of No 6 injector, so just need to sort that.