JD300 Rough Start and Stalls when moving or using hydraulics

   / JD300 Rough Start and Stalls when moving or using hydraulics #11  
JD 300 uses a closed center hydraulic system, so there aren't any relief valves. If bogging when using hydraulics that's an engine power issue.

You also said it's bogging when driving it, and the drive system is not powered by hydraulics, so again points to an engine power issue. You are on the right track to trace fuel supply.

Oil coming out the dipstick indicates to me you got a bunch of water in there that overfilled it. If it went around the boots, that's a lot of water to make it past a a small area, unless it was parked under a gutter or edge of a roof or something to direct a stream there. Either way you'll want to fix those boots and change the oil, but monitor the level after that to make sure you don't have another leak.

Regular hy gard, not low vis.

From what I recall when i had mine, left shifter is park, hi and low range. Right shifter is gears.
 
   / JD300 Rough Start and Stalls when moving or using hydraulics
  • Thread Starter
#12  
JD 300 uses a closed center hydraulic system, so there aren't any relief valves. If bogging when using hydraulics that's an engine power issue.

You also said it's bogging when driving it, and the drive system is not powered by hydraulics, so again points to an engine power issue. You are on the right track to trace fuel supply.

Oil coming out the dipstick indicates to me you got a bunch of water in there that overfilled it. If it went around the boots, that's a lot of water to make it past a a small area, unless it was parked under a gutter or edge of a roof or something to direct a stream there. Either way you'll want to fix those boots and change the oil, but monitor the level after that to make sure you don't have another leak.

Regular hy gard, not low vis.

From what I recall when i had mine, left shifter is park, hi and low range. Right shifter is gears.
Honestly my hunch is also that the hydrualic issue is separate from the engine dying from a load being put on it. I'm trying to see if there is a fuel restriction somewhere but not sure how. When it is not in gear and moving..I can rev up as high as I want and it stays on perfectly.

You are correct with the shifters...that is the correct arrangement.
 
   / JD300 Rough Start and Stalls when moving or using hydraulics #13  
Honestly my hunch is also that the hydrualic issue is separate from the engine dying from a load being put on it. I'm trying to see if there is a fuel restriction somewhere but not sure how. When it is not in gear and moving..I can rev up as high as I want and it stays on perfectly.

You are correct with the shifters...that is the correct arrangement.
Revving high doesn't take much fuel. Operating under power does. Operating under power while revving is what takes the most fuel. But high rpms with no load won't be enough to show you a fuel restriction.

I'm not totally sure the fuel configuration on that machine, but in general you can test fuel supply by disconnecting the line before the carb, making sure you have good flow to there. You may need to crank the engine while doing this depending on the fuel pump setup. If you have good flow to there, then a carb cleaning is in order.
 
   / JD300 Rough Start and Stalls when moving or using hydraulics
  • Thread Starter
#14  
I feel like I need to give the full background to what happened so far.

i bought the backhoe, the guy said it overheats when you use it for a little while, and I will know because radiator cap area will smoke. I brought it home and it worked fine..this was like a week ago.

I used it to dig some holes and flatten things etc. At some point, I think the backhoe overheated and it started to sound horrible and lose power. I also saw white smoke from the tube on the left side (I believe it did its the crankcase vent?). It also started spewing coolant out of the top hole when I turned it off. I did some research and it suggested a blown head gasket do I used a additive in the radiator that fixes the head gasket.

As I was reving that through, the backhoe shut off. I couldn't turn it back on. Turned out to be the batteries. So I charged both batteries and it worked again. The sound went away and it wasn't overheating like before. And less white smoke. I did touch the carburetor knobs at this time because to start it up I would need to pull the choke in and out and in and out while holding the key dow. to get it started. This wasn't the case when I brought it home.

I changed the crankcase oil with 10w30 at the suggestion of the auto shop guy, but thought this might be the issue so I changed it back out to SAE 30, which seemed to help a little bit. I haven't drained and refilled the radiator since it isn't losing coolant anymore.
 
   / JD300 Rough Start and Stalls when moving or using hydraulics
  • Thread Starter
#15  
Update, draining the hydrualic oil now...it was a lot of gross, milky brown. Do I need to drain it from both drains or is one drain okay?

I adjusted the fuel needle on the carburetor and now, it doesn't turn off when I am moving around on any gear! It still powers down a little when I'm using the loader and excavator to a point where it will turn off after 3 or 4 lifts. I'm hoping that's the hydrualic oil part.

One new surprising and scary symptom. When I try to start it up after a little bit of sitting, it makes a big pop, with a lot of white smoke, and the engine oil dipstick flies out of the hole..doesn't do it after that when I'm trying to turn it on. Am I building some sort of pressure in there?

Thank you all
 
   / JD300 Rough Start and Stalls when moving or using hydraulics #16  
JD 300 uses a closed center hydraulic system, so there aren't any relief valves.
Sorry but your statement that JD 300 series hyd system utilizes no relief valves is inaccurate. The factory valve that controls front end loader & backhoe that fit 300 has relief valves.
 

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   / JD300 Rough Start and Stalls when moving or using hydraulics #17  
I feel like I need to give the full background to what happened so far.

i bought the backhoe, the guy said it overheats when you use it for a little while, and I will know because radiator cap area will smoke. I brought it home and it worked fine..this was like a week ago.

I used it to dig some holes and flatten things etc. At some point, I think the backhoe overheated and it started to sound horrible and lose power. I also saw white smoke from the tube on the left side (I believe it did its the crankcase vent?). It also started spewing coolant out of the top hole when I turned it off. I did some research and it suggested a blown head gasket do I used a additive in the radiator that fixes the head gasket.

As I was reving that through, the backhoe shut off. I couldn't turn it back on. Turned out to be the batteries. So I charged both batteries and it worked again. The sound went away and it wasn't overheating like before. And less white smoke. I did touch the carburetor knobs at this time because to start it up I would need to pull the choke in and out and in and out while holding the key dow. to get it started. This wasn't the case when I brought it home.

I changed the crankcase oil with 10w30 at the suggestion of the auto shop guy, but thought this might be the issue so I changed it back out to SAE 30, which seemed to help a little bit. I haven't drained and refilled the radiator since it isn't losing coolant anymore.

These symptoms sounds as if the engine suffered what is called four corner seize. It could have temporarily seized the piston to liner. if so, it will likely happen again. Seems like there is a lot of unburnt gasses in crankcase to cause explosion in crankcase and blow out dipstick. Maay need an overhaul to fix. I would recommend compression test and/or cylinder leakdown test to verify.
 
   / JD300 Rough Start and Stalls when moving or using hydraulics #18  
Sorry but your statement that JD 300 series hyd system utilizes no relief valves is inaccurate. The factory valve that controls front end loader & backhoe that fit 300 has relief valves.
Hm, no reason to apologize, thank you for correcting me. They do all have closed center hydraulics though, correct? My bigger point was that the system pressure is controlled by the pump, not a relief valve. So running to the end of a function would load an open center system, but would not load a closed center system. Relief valves aren't a part of normal operating parameters like they are with an open center system.

As I recall with mine, an excess load will cause destroking of the pump, not bypass through a relief valve. My response was just to the suggestion of plugged relief valves or something to that effect. It is my understanding that the pump will destroke to control pressure. That's how it worked with mine, maybe they aren't all the same.

I suspect those relief valves are there to control overpressurizing if an excess load is applied in another manner - I.E. curling a very heavy load with loader arms raised, allowing the arms to drop before buckling a cylinder or blowing a line.
 
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   / JD300 Rough Start and Stalls when moving or using hydraulics #19  
I feel like I need to give the full background to what happened so far.

i bought the backhoe, the guy said it overheats when you use it for a little while, and I will know because radiator cap area will smoke. I brought it home and it worked fine..this was like a week ago.

I used it to dig some holes and flatten things etc. At some point, I think the backhoe overheated and it started to sound horrible and lose power. I also saw white smoke from the tube on the left side (I believe it did its the crankcase vent?). It also started spewing coolant out of the top hole when I turned it off. I did some research and it suggested a blown head gasket do I used a additive in the radiator that fixes the head gasket.

As I was reving that through, the backhoe shut off. I couldn't turn it back on. Turned out to be the batteries. So I charged both batteries and it worked again. The sound went away and it wasn't overheating like before. And less white smoke. I did touch the carburetor knobs at this time because to start it up I would need to pull the choke in and out and in and out while holding the key dow. to get it started. This wasn't the case when I brought it home.

I changed the crankcase oil with 10w30 at the suggestion of the auto shop guy, but thought this might be the issue so I changed it back out to SAE 30, which seemed to help a little bit. I haven't drained and refilled the radiator since it isn't losing coolant anymore.
Seems there's a lot going on here.

The overheating - I would not run this machine without a temperature gauge. Frankly, I wouldn't run any machine of this complexity and cost without a temp gauge. But that's especially true for one that has known cooling issues. Waiting for signs to show up is asking to cause damage. It is also possible that a loose cap will cause a little bit of steam before things are actually too warm, and you may not have an actual overheating problem. You have no way to know unless you are measuring the temperature directly.

The head gasket - additives (IMO) are a last ditch effort to correct an issue that you are unwilling to fix correctly. If there is a head gasket issue on say, an older car, it might not be worth the cost of fixing directly. So that additive might be worth a shot to get a little bit more life out of something that might be going to the junkyard. But it can reduce cooling efficiency if it plugs or coats the wrong area. I am not sure you had a head gasket issue at all, to determine that you need more diagnosis than is written above.

The carburetor - do you have experience adjusting carburetors? Often times there is a procedure to do this, and it's not something to mess with without the appropriate tools and knowledge of what the adjustments do. Running an engine with an incorrect mixture can cause degraded performance and sometimes cause damage.

The Oil - I don't buy that you can notice a difference between 10w-30 and SAE 30 from the operators seat. Winter starting would probably be improved with 10w-30.

The Hydraulic oil - you need to drain from every drain plug, not just one. I think there might be 3? But I don't remember specifically.

The batteries - It sounds like maybe they aren't charging. But that would need to be checked with a meter.

I wonder if you'd be well served to find someone in your area that knows their way around equipment to take a look at this for you. Seems there are many things going on, and a little time with someone that knows equipment would likely be of great value for you. I would have them install a temp gauge, look over the rest of the machine, and go from there. We can try to help from the internet, but you may get sent in the wrong direction, and even amongst those that know, being with a machine physically is tremendously more valuable than trying to diagnose one through a keyboard.
 
   / JD300 Rough Start and Stalls when moving or using hydraulics
  • Thread Starter
#20  
Seems there's a lot going on here.

The overheating - I would not run this machine without a temperature gauge. Frankly, I wouldn't run any machine of this complexity and cost without a temp gauge. But that's especially true for one that has known cooling issues. Waiting for signs to show up is asking to cause damage. It is also possible that a loose cap will cause a little bit of steam before things are actually too warm, and you may not have an actual overheating problem. You have no way to know unless you are measuring the temperature directly.

The head gasket - additives (IMO) are a last ditch effort to correct an issue that you are unwilling to fix correctly. If there is a head gasket issue on say, an older car, it might not be worth the cost of fixing directly. So that additive might be worth a shot to get a little bit more life out of something that might be going to the junkyard. But it can reduce cooling efficiency if it plugs or coats the wrong area. I am not sure you had a head gasket issue at all, to determine that you need more diagnosis than is written above.

The carburetor - do you have experience adjusting carburetors? Often times there is a procedure to do this, and it's not something to mess with without the appropriate tools and knowledge of what the adjustments do. Running an engine with an incorrect mixture can cause degraded performance and sometimes cause damage.

The Oil - I don't buy that you can notice a difference between 10w-30 and SAE 30 from the operators seat. Winter starting would probably be improved with 10w-30.

The Hydraulic oil - you need to drain from every drain plug, not just one. I think there might be 3? But I don't remember specifically.

The batteries - It sounds like maybe they aren't charging. But that would need to be checked with a meter.

I wonder if you'd be well served to find someone in your area that knows their way around equipment to take a look at this for you. Seems there are many things going on, and a little time with someone that knows equipment would likely be of great value for you. I would have them install a temp gauge, look over the rest of the machine, and go from there. We can try to help from the internet, but you may get sent in the wrong direction, and even amongst those that know, being with a machine physically is tremendously more valuable than trying to diagnose one through a keyboard.
Thank you, I been looking for someone who could come look at it for me, but haven't been able to find anyone. The local John deere ag pro said it is industrial and old so they don't deal with it, and wouldn't really even talk to me about it.

At this point, I got it back to running pretty well. If I'm going up a hill in the 8th gear, it stalls out, but if I do it in gear 5 or 6 it works fine. It still stalls out if I overuse the loader or backhoe but if I go slow, and let it Rev up again, it is working. Moving around on flat ground is fine too.

The only issue still is when starting it up. I need to hold the key for like 10 seconds before I can let go and have the machine keep going. 1 time out of 5, the dipstick from the crankcase oil is flying out with a lot of white smoke from the exhaust up top and from the dipstick hole. When that happens, cranking stops and starts again. If I could figure that piece out, I can use it around the house okay. I do have the manual that suggested the carburetor settings, and went off that.

Water doesn't seem to be getting into the hydraulic system as far as I can tell since the full flush
 
 
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