Green Tractor Talk banner

1 - 15 of 15 Posts

·
Registered
Joined
·
554 Posts
Discussion Starter #1
My grandma has a X495 diesel mower. It overheats and when you shut it off coolant leak from the reservoir cap. I have already replaced the thermostat. Moving to the water pump next. Just wanted to see if anyone else has ideas.
 

·
Registered
Joined
·
3,871 Posts
Is the radiator screen clean.I get grass between the rad and the hydro cooler.I would also try the rad cap before doing the water pump.
I have the 62" deck and would get a lot of blowout out the front of the deck and then sucked into the radiator area.The screen would get some but a lot was in between the rad and the hydro cooler.That for sure will make it run hot and overheat.Those engines need the airflow.
 

·
Registered
Joined
·
3,228 Posts
It was clean when I saw it, whether or not the person running it is checking I don't know.


This is the first thing I would find out.

Almost sounds like it has 2 problems.

Overheating, especially after you turn the engine off. This is somewhat common because you are stopping the flow of coolant and oil. When restarting the engine it should cool back down fairly quick.

Also a coolant leak from the radiator neck, cap, surge tank or the hose that connects the 2. Radiator caps are cheap and frequently go bad. If it's more than a few years old replace it. If the cap is the original one that came with the tractor. Definitely replace it! You can get a special tool to check if the cap is bad. You attach the cap and pump it up like a basketball. It should hold the amount of pressure written on the cap. A local parts store may have one they will let you use.

Next common problem is the overflow hose. It needs to be in good condition and clamped at both ends.
 

·
Registered
Joined
·
590 Posts
Do a flush/boil out on the radiator, you got to have flow for it to cool. If you can, put a light on one side of the radiator and look thru the fins on the other side. Radiator might look clean on outside but be plugged up with seeds, chaff, grass, etc. inbetween the fins. Seeing just some light is not good enough, make sure it is totally clean.

I am just adding to the other very good troubleshooting/suggestions.

Just hope the the motor was not overheated long enough for not damage to occur! Good Luck! :bigthumb:
 

·
Registered
Joined
·
1,751 Posts
Not alot of mechanical failures and overheating I have seen on these. Most are caused by plugged screens and rads. Seen a few clogged up radiators inside where straight water was used. I haven't seen many blown head gaskets but its worth a look see. Remove cap and crank it up.. If it starts spewing out..might have an issue. Also.. And someone correct me if wrong.. The blades/pto should cut off when overheating to reduce load on engine.

Sent from my LGL52VL using Tapatalk
 

·
Registered
Joined
·
554 Posts
Discussion Starter #8
Correct the blades do shut down. We don't run anything but John Deere oils and fluids. Even in my 7.3. Deere is rated higher anyway. I'll start replacing caps and checking lines. Other people like to use and abuse her stuff but I'd rather see it looked after before the fix gets real expensive.
 

·
Registered
Joined
·
3,228 Posts
I'd recommend checking the engine temperature with a temp gun vs using the dashboard gauge. They are way more accurate. Plus you can use it to check for a internally clogged radiator. If you find a cold spot fluid is not moving inside it.
 

·
Registered
Joined
·
86 Posts
Correct the blades do shut down. We don't run anything but John Deere oils and fluids. Even in my 7.3. Deere is rated higher anyway. I'll start replacing caps and checking lines. Other people like to use and abuse her stuff but I'd rather see it looked after before the fix gets real expensive.
There is a over temperature switch that operates @230 degrees F. So the blades should shut off when it is hot. I bought a laser temp gun and it is a very handy tool. My X595 operates at around 170 degrees with no load.
 

·
Registered
Joined
·
1,997 Posts
Hiya,

I would say the most likely issue is plugged cooling fins on the outside of the radiator core. I see a lot of turf equipment with radiators plugged solid with dirt and grass. Easy way to check is to put a drop light on one side of the radiator and look through from the other side, if you can't see the light, you have found your issue.

I blow out the radiator with compressed air in reverse direction of the running airflow after every time I mow and have yet to have an issue.
 

·
Registered
Joined
·
352 Posts
This has been said but carefully check your radiator and screen. The screen pulls out from the side. I had the same problem you had and when I opened the hood and looked into the radiator area I really could not see any blockage, so I moved on with other possible causes. But when I got down and pulled that screen out and shone a flashlight in there I realized it was totally plugged with fine chaff. Blew it out and it was good to go. Maybe you have done this already in which case you're on the right path with the other suggestions provided.
 

·
Premium Member
Joined
·
8,818 Posts
Usually, when the water pump fails, it is leaking water out of the impeller shaft bearing (behind the flange where the fan mounts) and / or the pump is squealing or making a grinding sound, because of internal failure. A sure sign of water pump failure is if the cooling fan is at all loose or "wobbles" on the pump shaft when you grab it and attempt to move it. Often, the first sign some operators will notice is a metal to metal banging / grinding sound where the fan is actually hitting the radiator cooling shroud when spinning because of the shaft bearing failure permitting the fan to wobble and not spin in a balanced manner. This will wreck lots of parts quickly so it should not be allowed to continue under any circumstances.

Failure of the water pumps is not real common on the Yanmar diesels, even with machines which have a few thousand hours on them. If the pump isn't leaking nor making any noise and it still rotates freely, it's unlikely the water pump is bad. The pumps are pricey on these ($175 to $350) so don't just replace it unless you are sure it has failed.

It sounds like a typical radiator cap failure. I would just replace the radiator cap if it is a few years old. Get the correct cap from Deere (part number M802715) as it has to be the right pressure (13 pounds) for the system to work correctly. Only use the correct cap as it makes a difference. Please note that the Deere parts source shows that the original caps were different based upon your engine tag number but when you look them both up, Deere is now using the same part number for both engine tag numbers (M802715).

FYI, Deere calls the overflow tank cap the "Cap" and the radiator cap the "Filler Cap". So make sure you specify the part number should you be calling around. I am sure the dealer stocks these as they fit many applications.

I have heard some people say "If it fits the radiator, it's ok to use". Well, not necessarily true in the case of radiator caps, they need to be designed to provide pressure relief should the internal pressure exceed the system designed pressure of 13 pounds on your tractor and allow the "expanded" coolant to flow into the overflow tank. If the coolant levels are low and the cooling system pressure reaches the cap pressure threshold, then the fluid is pulled from the overflow tank and back into the radiator so your system maintains the appropriate coolant fluid levels. That's why you want to maintain the correct fluid level in the overflow tank at all times.

Also check the radiator hoses to make sure they haven't collapsed internally or have gotten so weak from the heat that they collapse when they get hot. The flat spots of the hose are more likely to do this than the molded parts such as bends, etc. I have seen older hoses weaken and significantly restrict coolant flow, the hotter the hoses get, the more they restrict the coolant if they are collapsing. The hoses on your tractor are quite short in length so collapsing to cause restriction is rare, but still check them.

The Yanmar diesels in these tractors also use a steel tube for bringing the coolant from the bottom of the radiator back up for circulation. While it's not very likely, It's worth taking a look to make sure somehow this "tube" or line hasn't been damaged and is restricting coolant flow. It's number 27 in the diagram.



As others have suggested, you can get a decent infrared temp gun for under $40 and even under $20 when they are on sale. They are invaluable for diagnosing such problems. Plus they are entertaining when you are bored as you can check the surface temp of all sorts of things and it's actually interesting.

Take a reading on the different sections of the radiator and you will see exactly how the coolant flow is going. Same with the engine block and the hoses. The hottest readings should be the upper part of the radiator where the coolant enters the radiator from the engine and you will see noticeable decline in temps as the coolant passes down through the radiator.

Please note that the radiator on these tractors also serves as a hydraulic system fluid cooling source. The very bottom of the radiator has two steel lines attached. These lines are circulating hydro fluid from the main system pump, which is located under the seating platform on your tractor. The hydraulic fluid is obviously segregated into it's own cooling tanks so it doesn't contaminate the coolant and vice versa.

But in the operation of your tractor, both engine coolant and hydraulic (Hydro) oil are both circulating through their designated sections of the radiator. So when you are scanning the radiator with your new infrared temp gun, when you reach the very bottom of the radiator, you will notice the lowest part of the radiator can show temps higher than the bottom 1/3rd of the radiator. This is because one of the cooling methods for the hydraulic fluid is to use the cooler temps of the coolant in the bottom of the radiator to help reduce the hydraulic fluid temps in the hydrostatic cooler on the bottom of the radiator.

Note, there shouldn't be a large temperature difference (of say 100 degrees) between the lower part of the radiator and the hydro fluid cooler, but I have noticed a difference between the two, especially of you have been operating the PTO as the clutch's engaged in the hydro system will cause a measurable increase in the hydro fluid temp.

Once an engine reaches operating temperature which is 160 or 180 degrees, the thermostat will begin to open and it remains open at either 165 or 185 degrees, depending upon which thermostat you use. The system is designed to hold the coolant in the radiator so it can be cooled with the airflow from the fan and when the thermostat opens when it reaches operating temp, then the coolant flows from the radiator into the engine and on the opposite end, from the engine block through the water pump into the top of the radiator.

When installed in the tractor, the thermostat opens in the downward position when the spring pulls it open as it reaches the temp range. This permits the coolant to flow from the water pump into the radiator. As the coolant flows down through the radiator, the affect of the air being pulled over the radiator fins and the coolant dissipating heat into the fins as it provides the cooling process.

As the now "cooler" fluid reaches the bottom of the radiator, it flows back up through the return line (#27 on the diagram) to the water pump and either is introduced into the engine block through the bypass or it circulates back through the radiator. As the engine heats the coolant in the block, once the thermostat reaches the temp range again, it opens allowing the cooler water into the block and the heated water from the block to pass through the radiator.

Since the water pump is constantly spinning when the engine is running, it's pushing coolant at all times, it's only a matter of where. The radiator cap provides 13 pounds of pressure, which is critical for keeping the coolant moving properly and helps cool it. The pressure in the system comes from the heat of the coolant fluid, which is why you never open a warm or hot radiator cap and why you can (very carefully) remove the cap when the vehicle is cold, even if the engine is running.


Diesel engines typically like a higher engine operating temperature (they seem to run more efficient), which is why IN THE WINTER, some cover their tractors hood side panels with a piece of cardboard on the inside of the hood cut to fit the recess area and even place some cardboard on the outside of their radiator screen,to restrict the cold air flow and allow the engine to remain in the ideal operating temp range. Some owners run the 160 degree thermostat in the summer and the 180 degree in the winter. Never restrict fresh airflow if you don't have an actual coolant temperature gauge on the tractor as you could easily damage the engine if it is severely overheated. Never rely solely on an "Idiot Light" to advise you of excessive engine temperatures on diesel tractors.

If you are not finding anything obvious, you can also pressure test the entire system with a special hand held pump to see if you have a bad head gasket, but I can honestly say I have never seen or heard of head gasket problems on these diesels. Stores such as AutoZone and O'Reilly Automotive loan "specialty tools", most at no charge. So if you need to pressure check the system and don't have access to the tool, check with these stores. As long as the tool has a adapter which will fit the top of the radiator where the cap is installed, the tool should work. But make sure you don't apply too much pressure to the system (above 15 pounds, 2 pounds over the cap limit) with the test pump as you can damage components.

Also, it's not a bad idea to rinse the radiator from the back side (where the fan and radiator shroud are located) towards the screen side with a garden hose and don't be shy with the water. Don't blast the radiator with high pressure as it can collapse the cooling fins or even rupture the radiator, just flush lots of water through the fins from the hose without a nozzle. Obviously, don't attempt to do this with the engine running as you risk damaging the fan and getting hurt.

The natural wind flow direction is for the radiator to draw the air through the radiator starting at the screen side. By rinsing from the opposite side, you are washing out the debris backwards from it's direction of entry. Sometimes, over time, the very small dust and dirt which gets through the screen accumulates in the radiator fins and it's not evident to the naked eye.

Good luck and let us know what you find.
 

·
Premium Member
Joined
·
7,707 Posts
This is the first thing I would find out.

Almost sounds like it has 2 problems.

Overheating, especially after you turn the engine off. This is somewhat common because you are stopping the flow of coolant and oil. When restarting the engine it should cool back down fairly quick.

Also a coolant leak from the radiator neck, cap, surge tank or the hose that connects the 2. Radiator caps are cheap and frequently go bad. If it's more than a few years old replace it. If the cap is the original one that came with the tractor. Definitely replace it! You can get a special tool to check if the cap is bad. You attach the cap and pump it up like a basketball. It should hold the amount of pressure written on the cap. A local parts store may have one they will let you use.

Next common problem is the overflow hose. It needs to be in good condition and clamped at both ends.
Usually, when the water pump fails, it is leaking water out of the impeller shaft bearing (behind the flange where the fan mounts) and / or the pump is squealing or making a grinding sound, because of internal failure. A sure sign of water pump failure is if the cooling fan is at all loose or "wobbles" on the pump shaft when you grab it and attempt to move it. Often, the first sign some operators will notice is a metal to metal banging / grinding sound where the fan is actually hitting the radiator cooling shroud when spinning because of the shaft bearing failure permitting the fan to wobble and not spin in a balanced manner. This will wreck lots of parts quickly so it should not be allowed to continue under any circumstances.

Failure of the water pumps is not real common on the Yanmar diesels, even with machines which have a few thousand hours on them. If the pump isn't leaking nor making any noise and it still rotates freely, it's unlikely the water pump is bad. The pumps are pricey on these ($175 to $350) so don't just replace it unless you are sure it has failed.

It sounds like a typical radiator cap failure. I would just replace the radiator cap if it is a few years old. Get the correct cap from Deere (part number M802715) as it has to be the right pressure (13 pounds) for the system to work correctly. Only use the correct cap as it makes a difference. Please note that the Deere parts source shows that the original caps were different based upon your engine tag number but when you look them both up, Deere is now using the same part number for both engine tag numbers (M802715).

FYI, Deere calls the overflow tank cap the "Cap" and the radiator cap the "Filler Cap". So make sure you specify the part number should you be calling around. I am sure the dealer stocks these as they fit many applications.

I have heard some people say "If it fits the radiator, it's ok to use". Well, not necessarily true in the case of radiator caps, they need to be designed to provide pressure relief should the internal pressure exceed the system designed pressure of 13 pounds on your tractor and allow the "expanded" coolant to flow into the overflow tank. If the coolant levels are low and the cooling system pressure reaches the cap pressure threshold, then the fluid is pulled from the overflow tank and back into the radiator so your system maintains the appropriate coolant fluid levels. That's why you want to maintain the correct fluid level in the overflow tank at all times.

Also check the radiator hoses to make sure they haven't collapsed internally or have gotten so weak from the heat that they collapse when they get hot. The flat spots of the hose are more likely to do this than the molded parts such as bends, etc. I have seen older hoses weaken and significantly restrict coolant flow, the hotter the hoses get, the more they restrict the coolant if they are collapsing. The hoses on your tractor are quite short in length so collapsing to cause restriction is rare, but still check them.

The Yanmar diesels in these tractors also use a steel tube for bringing the coolant from the bottom of the radiator back up for circulation. While it's not very likely, It's worth taking a look to make sure somehow this "tube" or line hasn't been damaged and is restricting coolant flow. It's number 27 in the diagram.



As others have suggested, you can get a decent infrared temp gun for under $40 and even under $20 when they are on sale. They are invaluable for diagnosing such problems. Plus they are entertaining when you are bored as you can check the surface temp of all sorts of things and it's actually interesting.

Take a reading on the different sections of the radiator and you will see exactly how the coolant flow is going. Same with the engine block and the hoses. The hottest readings should be the upper part of the radiator where the coolant enters the radiator from the engine and you will see noticeable decline in temps as the coolant passes down through the radiator.

Please note that the radiator on these tractors also serves as a hydraulic system fluid cooling source. The very bottom of the radiator has two steel lines attached. These lines are circulating hydro fluid from the main system pump, which is located under the seating platform on your tractor. The hydraulic fluid is obviously segregated into it's own cooling tanks so it doesn't contaminate the coolant and vice versa.

But in the operation of your tractor, both engine coolant and hydraulic (Hydro) oil are both circulating through their designated sections of the radiator. So when you are scanning the radiator with your new infrared temp gun, when you reach the very bottom of the radiator, you will notice the lowest part of the radiator can show temps higher than the bottom 1/3rd of the radiator. This is because one of the cooling methods for the hydraulic fluid is to use the cooler temps of the coolant in the bottom of the radiator to help reduce the hydraulic fluid temps in the hydrostatic cooler on the bottom of the radiator.

Note, there shouldn't be a large temperature difference (of say 100 degrees) between the lower part of the radiator and the hydro fluid cooler, but I have noticed a difference between the two, especially of you have been operating the PTO as the clutch's engaged in the hydro system will cause a measurable increase in the hydro fluid temp.

Once an engine reaches operating temperature which is 160 or 180 degrees, the thermostat will begin to open and it remains open at either 165 or 185 degrees, depending upon which thermostat you use. The system is designed to hold the coolant in the radiator so it can be cooled with the airflow from the fan and when the thermostat opens when it reaches operating temp, then the coolant flows from the radiator into the engine and on the opposite end, from the engine block through the water pump into the top of the radiator.

When installed in the tractor, the thermostat opens in the downward position when the spring pulls it open as it reaches the temp range. This permits the coolant to flow from the water pump into the radiator. As the coolant flows down through the radiator, the affect of the air being pulled over the radiator fins and the coolant dissipating heat into the fins as it provides the cooling process.

As the now "cooler" fluid reaches the bottom of the radiator, it flows back up through the return line (#27 on the diagram) to the water pump and either is introduced into the engine block through the bypass or it circulates back through the radiator. As the engine heats the coolant in the block, once the thermostat reaches the temp range again, it opens allowing the cooler water into the block and the heated water from the block to pass through the radiator.

Since the water pump is constantly spinning when the engine is running, it's pushing coolant at all times, it's only a matter of where. The radiator cap provides 13 pounds of pressure, which is critical for keeping the coolant moving properly and helps cool it. The pressure in the system comes from the heat of the coolant fluid, which is why you never open a warm or hot radiator cap and why you can (very carefully) remove the cap when the vehicle is cold, even if the engine is running.


Diesel engines typically like a higher engine operating temperature (they seem to run more efficient), which is why IN THE WINTER, some cover their tractors hood side panels with a piece of cardboard on the inside of the hood cut to fit the recess area and even place some cardboard on the outside of their radiator screen,to restrict the cold air flow and allow the engine to remain in the ideal operating temp range. Some owners run the 160 degree thermostat in the summer and the 180 degree in the winter. Never restrict fresh airflow if you don't have an actual coolant temperature gauge on the tractor as you could easily damage the engine if it is severely overheated. Never rely solely on an "Idiot Light" to advise you of excessive engine temperatures on diesel tractors.

If you are not finding anything obvious, you can also pressure test the entire system with a special hand held pump to see if you have a bad head gasket, but I can honestly say I have never seen or heard of head gasket problems on these diesels. Stores such as AutoZone and O'Reilly Automotive loan "specialty tools", most at no charge. So if you need to pressure check the system and don't have access to the tool, check with these stores. As long as the tool has a adapter which will fit the top of the radiator where the cap is installed, the tool should work. But make sure you don't apply too much pressure to the system (above 15 pounds, 2 pounds over the cap limit) with the test pump as you can damage components.

Also, it's not a bad idea to rinse the radiator from the back side (where the fan and radiator shroud are located) towards the screen side with a garden hose and don't be shy with the water. Don't blast the radiator with high pressure as it can collapse the cooling fins or even rupture the radiator, just flush lots of water through the fins from the hose without a nozzle. Obviously, don't attempt to do this with the engine running as you risk damaging the fan and getting hurt.

The natural wind flow direction is for the radiator to draw the air through the radiator starting at the screen side. By rinsing from the opposite side, you are washing out the debris backwards from it's direction of entry. Sometimes, over time, the very small dust and dirt which gets through the screen accumulates in the radiator fins and it's not evident to the naked eye.

Good luck and let us know what you find.
I will THIRD (H-D & Sulley were 1st & 2nd) replacing the radiator cap. The cap pressure setting increase the boiling temp of the coolant. A bad cap would allow coolant to escape at a lower than design temp. If that does not fix the problem next check the radiator for external and/or internal plugging.
 
1 - 15 of 15 Posts
Top