PBradley
New member
I have been reading some post on here and some advised that a good injector will "stall" or "kill" the tractor. My tractor has a change in RPM but does not stop running. Elaborate on "stall"
Elaborate on cracking injector lines
- Thread starter PBradley
- Start date
- Views: 13688
mark777
Veteran Member
- Joined
- May 16, 2004
- Messages
- 1,300
- Location
- S.E Texas
- Tractor
- Ym1300d-1401D-1601D , 1610D & Massey Ferguson 1020
PBradley,
I hope to keep this simple as it's more difficult to explain that actually perform.
IE: A Two Cylinder Engine -
The quick and accurate way to determine if an injector is bad on a diesel engine is, while the engine is running, loosen one injector line at a time.
IF - the engine runs while fuel is seeping from the loosened line fitting, THAT is the bad injector or...
IF - the engine stalls while the line is loosened and fuel seeping passed the line fitting, THAT is the good injector.
The same trouble shooting works for multiple cylinder diesel engines as well. It won't stall, but each GOOD injector with an opened line will cause the engine to stumble and run rough. When there is NO change in the engines performance, AND a line is loose at one particular injector - Bingo!...that's the bad one.
Hope this helps.
Mark
I hope to keep this simple as it's more difficult to explain that actually perform.
IE: A Two Cylinder Engine -
The quick and accurate way to determine if an injector is bad on a diesel engine is, while the engine is running, loosen one injector line at a time.
IF - the engine runs while fuel is seeping from the loosened line fitting, THAT is the bad injector or...
IF - the engine stalls while the line is loosened and fuel seeping passed the line fitting, THAT is the good injector.
The same trouble shooting works for multiple cylinder diesel engines as well. It won't stall, but each GOOD injector with an opened line will cause the engine to stumble and run rough. When there is NO change in the engines performance, AND a line is loose at one particular injector - Bingo!...that's the bad one.
Hope this helps.
Mark
mark777
Veteran Member
- Joined
- May 16, 2004
- Messages
- 1,300
- Location
- S.E Texas
- Tractor
- Ym1300d-1401D-1601D , 1610D & Massey Ferguson 1020
What???
Wait a minute now.......LOL.
Cracking the line pressure to a diesel injector is like...well...pulling a plug wire off a gasoline engine. And if you have a two cylinder gas engine with both plug wires off it won't go. Not even a little bit
.
Are you loosening the lines at the injector and not at the pump? Are the lines really loose, wet, drippy, messy, loose?
I must not be understanding you correctly...what model Yanmar do you have?
Mark
Wait a minute now.......LOL.
Cracking the line pressure to a diesel injector is like...well...pulling a plug wire off a gasoline engine. And if you have a two cylinder gas engine with both plug wires off it won't go. Not even a little bit
.Are you loosening the lines at the injector and not at the pump? Are the lines really loose, wet, drippy, messy, loose?
I must not be understanding you correctly...what model Yanmar do you have?
Mark
MJPetersen
Veteran Member
PBradley,
Welcome to TBN, this is a great forum and place to learn lots about your tractor and using it. Whether it actually stalls or not depends on how much you open the injector line, how fast the engine is running, and the condition of the injectors.
I am somewhat curious why you are even doing this. Is your engine not running properly that makes you suspect something. Usually you do this if you are trying to isolate which cylinder is miss firing. That is that you are trying to isolate which of the 2 (or 3) cylinders is not working as it ought. If a 2 cylinder engine is running at low idle then the engine will stall or just barely continue running if that cylinder is working and the other cylinder is also working. That would be a sign that it is normal. if there is no change in RPM or very little change, then there is a problem in the cylinder whose line you opened. The injector is not flowing or there are other problems in the cylinder. This is the same test and result that mechanics use on gasoline engines--as it is like pulling a spark-plug wire.
Maybe some theory on the way that injectors work is in order for those not familiar with diesel engines. Injectors are designed to finely atomize the fuel by spraying the fuel through tiny holes in the tip. This spray has to be timed just like a spark in a gasoline engine (usually 20-30 degrees BTC). The injector pump pressurizes the fuel in sequence in the lines leading to the injectors, In each rotation of the engine, when a predetermined pressure is reached in the fuel line, the injector acts like a quick relief valve. It "pops" open and the high pressure fuel is forced through the little holes and ignites in the cylinder (or pre-combustion chamber) because of the heat created by the compression of the air. Because of the tiny ports, the close tolerances and the moving parts, the smallest particle of dirt can create problems.
What can go wrong in an injector? An injector can leak, that is allow fuel to flow through the injector at the wrong time and at low pressure. An injector can be plugged, either the ports in the nozzle, or one of the interior ports. An injector can be worn, the tolerances are too sloppy of it to hold the pressure and the fuel bypasses, or the spring pressure is weak and the injector "pops" too early and too low of pressure. Those are probably the most common faults, but guys that work with them can feel free to add or correct what I have written.
Mike
Welcome to TBN, this is a great forum and place to learn lots about your tractor and using it. Whether it actually stalls or not depends on how much you open the injector line, how fast the engine is running, and the condition of the injectors.
I am somewhat curious why you are even doing this. Is your engine not running properly that makes you suspect something. Usually you do this if you are trying to isolate which cylinder is miss firing. That is that you are trying to isolate which of the 2 (or 3) cylinders is not working as it ought. If a 2 cylinder engine is running at low idle then the engine will stall or just barely continue running if that cylinder is working and the other cylinder is also working. That would be a sign that it is normal. if there is no change in RPM or very little change, then there is a problem in the cylinder whose line you opened. The injector is not flowing or there are other problems in the cylinder. This is the same test and result that mechanics use on gasoline engines--as it is like pulling a spark-plug wire.
Maybe some theory on the way that injectors work is in order for those not familiar with diesel engines. Injectors are designed to finely atomize the fuel by spraying the fuel through tiny holes in the tip. This spray has to be timed just like a spark in a gasoline engine (usually 20-30 degrees BTC). The injector pump pressurizes the fuel in sequence in the lines leading to the injectors, In each rotation of the engine, when a predetermined pressure is reached in the fuel line, the injector acts like a quick relief valve. It "pops" open and the high pressure fuel is forced through the little holes and ignites in the cylinder (or pre-combustion chamber) because of the heat created by the compression of the air. Because of the tiny ports, the close tolerances and the moving parts, the smallest particle of dirt can create problems.
What can go wrong in an injector? An injector can leak, that is allow fuel to flow through the injector at the wrong time and at low pressure. An injector can be plugged, either the ports in the nozzle, or one of the interior ports. An injector can be worn, the tolerances are too sloppy of it to hold the pressure and the fuel bypasses, or the spring pressure is weak and the injector "pops" too early and too low of pressure. Those are probably the most common faults, but guys that work with them can feel free to add or correct what I have written.
Mike
The tractor is hard to start. I think I found part of the problem with the faulty fuel bowl. Temporarily fixed that. still hard to start. I have checked the governor and adjusted the valves. going to replace the governor spring while I have the covers off. I was curious about the posts on cracking the injector lines since mine kept running. Will try again when I get the spring at low idle. Will also check the compression.
I think it is internal due to oil dripping out of vent tube. Just trying to eliminate easier fixes first. Will consider overhaul or getting another tractor. May purchase another tractor and keep this one to play with. Would only need one with enough horsepower to have FEL and use boxblade or grader blade. Any suggestions
Jagmandave
Veteran Member
Do you open the throttle all the way when you try to start it? My Yanmar manual says to do this..........
