Foton 254 overheating.....in an odd way.

[greg_g]

I again advise to take care with radiator cap selection. Look for the pressure rating on the OE cap, it may be a metric number; either BAR or ATMOSPHERES. Typically it will be stamped on. Some I've found on the air side, others I've found on the coolant side. Whether or not it's got a zero in front, it will be a decimal number; like .3 or 0.3, perhaps .4 or 0.4. Multiplying a metric rating by 14.5 will give you the PSI

If however your OE cap actually had a PSI rating, you're not gaining anything by going to a higher pressure cap. Yes, it may have been defective, but the replacement should be of the same pressure rating.

That much notwithstanding, the coolant recovery system is good advice. I went with a simple $10 universal kit from JC Whitney.

//greg//

 

[RonMar]

+1 on the recovery tank. Once the system reaches cap relief pressure, it vents fluid. In a system with a recovery tank, this fluid is captured in the tank and drawn back into the rad when the system cools. So the rad should always be full. If you check the level in the radiator on a system with a recovery tank and it isn't full this tells you that you have a leak somewhere and the system cannot pull enough vacume to pull the fluid back into the rad... great clue when troubleshooting. It will also bubble and froth and show an oil ring from oil and combustion gasses when you blow a head gasket

 

[amafrank]

There are no seals in the barrel and plunger assemblies, they are a lapped fit and lubricated by the fuel. You have one or more bad plunger assemblies, but unfortunately they are not sold separately. Besides, you would need a test stand to set and calibrate them anyway. Test stands run around $20k for a good used one. You are looking at a new injection pump/governor assembly for around $450.00. Suggest you change oil frequently until you get a new pump assembly as this will lessen your chances of contaminating the engine lube oil through the pump shaft seal. The injection pump and governor share a common sump.

It would also help a lot to give the cooling system a good chemical flush and use a coolant designed for diesel engine service such as Final Charge Antifreeze Home Page or equivalent.

Let me suggest that you drop down one gear and try mowing again. Example: #2 L to #1 H. You might be slightly lugging the engine.

No lugging going on here. I normally mow in 4 low with no problems. I can mow in 1 high but it will lug then. I have been running this tractor for some time with no overheating so something has changed and its not my gear.

I will have a look at pulling the rad and cleaning it out good. I don't have any problems with internal crap or scale that can be seen. The thing is flushed and cleaned every fall then topped with proper diesel spec anti-freeze for winter. I use it in the winter sometimes for snow removal.

Right now there is no sign of fuel in the oil but I've not done any oil analysis. I'll keep an eye on it and change it frequently til I know for sure whats going on.

Higher pressure on the cap does help a lot as it raises the boiling point. If the engine can't handle 30psi or so something is wrong. I'm nowhere near that anyway..... I've seen no problems with seals or any of the cooling system having issues with the extra 5 psi or so. The old cap did leak and the spring was no good so it only took a little pressure to blow out a goodly amount of water. Thats a problem. I'm not leaking water out the cap anymore and the heat isn't coming up quick so that is a good thing compared to the old low pressure leaky cap.


Thanks guys. I won't be able to get back to check on anything for a week or so....on the road for a bit.

Frank

 

[greg_g]

Higher pressure on the cap does help a lot as it raises the boiling point. If the engine can't handle 30psi or so something is wrong. I'm nowhere near that anyway.....

If that's your decision, I respectfully suggest that you have the cooling system pressure tested. You identified your tractor as a 2006 FT254, which means it's almost certainly got the pre-EPA YangDong engine. That Y385T cooling system simply wasn't designed to accommodate 30 psi. I had two Y385Ts and one Y485T, all 3 pre-EPA. I can tell you from personal experience that going from the OE cap to a 15psi aftermarket cap resulted in coolant weeping from both at the radiator crimps and past the hose clamps. Plus, the cap spring is too strong to permit proper venting into a coolant recovery system. Been there, done that.

A 15psi cap is intended to work in conjunction with 90C and higher thermostats. It's an on-road thing. Your pre-EPA off-road diesel engine is designed to operate much cooler than that. In fact, the Y385T engine manual specifies a 70C to 80C operating range (158F to 176F). Paraphrased from the manual: "When coolant temperature is below 70C the thermostat closes, returning coolant to the radiator through the bypass hose. When coolant temp is between 70C~80C the thermostat opens, permitting full circulation through the engine and radiator".

But that's based upon an original equipment 0.3 to 0.4 bar pressure cap (4.35psi to 5.80 psi) working in conjunction with an original equipment 80C or lower thermostat. Going to a higher range thermostat and higher rated pressure cap simply takes the pre-EPA Y385T engine out of its "comfort zone". Yes, the OE radiator caps are crap. But they should be replaced with one that is as close to the OE range as possible. Why your tractor had no thermostat, I can't explain. But as indicated by the manual, you should have installed one with a cooler operating range.

It's good that you're going to remove the radiator for a more thorough cleaning. But I respectfully suggest that it be returned to the tractor to operate in conjuction with a more appropriate pressure cap and thermostat. Oh, one other thing; manual says fan belt should be tightened to permit at least 10mm but no more than 20mm deflection (0.4-0.8 inch). And even though this isn't in the Y385T manual, it's not a good idea to run other than a 50/50 coolant mix. Too much or too little coolant can also result in higher temperatures.

//greg//

 

[Bob Rooks]

To help clarify things, what Greg says is true. My statement about cooling systems being hydro tested to 30 psi relates to current domestic production. I have no idea what the Chinese test their systems to, if at all. The higher pressure systems are designed to operate at higher temperatures, such as 190°F to 200°F. This is for thermal efficiencies sake required for the latest tier emissions. I run my dozer (TY395) engine at 190°F with a 15 psi cap. The engine is very happy and there is a lot less soot in the oil, which by the way is approaching 275 hrs. and is still in excellent condition. Just FWIW. I might add that I also run a meticulously clean cooling system with a coolant filter - not many here are aware of the benefits of that.

 

[willi67]

I have a simple check that you may have already tried ...when its overheating run your hand, carefully ..lol, across the front of the radiator to see that its uniformly hot. I was chasing an overheating problem on a car and tried everything, turned out it was clogged up with scale inside the tubes, not all of it just one section. And the coolant was changed regularly.

 

[succor]

I have the same tractor, in which I get off as soon as the needle goes above 80C. I clean off the debris off the screen that I installed in front of the rad. I also keep the rad clean as well. I do have an overflow with the original rad cap and I redirected my air intake to the side of the tractor instead of right in front of the rad which helps a bit too.

 

[chuckottawa]

Haven't posted for a while but I've been watching....

I've got a 2006 254 that I bought new. The electrical system really sucks and has since new but thats another story.... Right now the issue is overheating. The tractor starts and runs fine for quite a while when mowing. I've got a 60" chinese bushhog style mower deck and it has been running fine since I got the whole rig, until last year. I can mow for about half an hour and the temp keeps climbing slowly. When it hits 100C I shut down and let it cool or take the garden hose to the radiator til its back in the green. Last year the issue turned out to be the cap which wasn't sealing properly. It would allow water to leak out the overflow til the level dropped enough to start the temps rising. I replaced the cap last summer with a higher pressure unit and that seemed to work. Now I'm back at the same issue only I'm not losing water through a faulty cap....its just getting hot. I checked the thermostat when I replaced the cap and there wasn't one in it. I put in a 180deg thermostat and that seemed to help too. I checked it and it is still working. The tractor only has 175hours on it since new and has good oil pressure, starts easy and runs good. I'm wondering if the governor is allowing too much fuel into the system and making more power than the radiator can dissipate? I pulled the dipstick on the injection pump/governor and its full of fuel. I don't think thats proper as it had been running just fine prior to this with engine oil. I haven't had much mowing this year due to the drought in the midwest and no grass to mow. It was fine in the spring (the injection pump) but now its not.....I've had overheaters before and they usually get hot quick or else they run fine. This one takes a long time to get too hot and thats puzzling.
Any suggestions are appreciated.

Frank

Removed the mesh inside the hood front grill ,now good air flow to the radiator engine runs much cooler.Might do the same on side grills,the mesh obstructs air flow.Bad design mesh only for looks.Powerful little tractor,i run a 6 foot finishing mower 1st gear on Hi temp holds around 80 degrees now,before 1/2 hour max cutting lawn and the rad would overflow and much lower gear speed.
Easy fix good luck .

 

[Bob Rooks]

Removed the mesh inside the hood front grill ,now good air flow to the radiator engine runs much cooler.Might do the same on side grills,the mesh obstructs air flow.Bad design mesh only for looks.Powerful little tractor,i run a 6 foot finishing mower 1st gear on Hi temp holds around 80 degrees now,before 1/2 hour max cutting lawn and the rad would overflow and much lower gear speed.
Easy fix good luck .

I believe that "mesh" is there for a purpose - to keep the radiator clean. I removed the screen (mesh) in front of my radiator and installed furnace filter media. Now all I do is change it periodically. Radiator is still clean as a whistle. You also should consider a coolant recovery bottle to keep the air out of your cooling system.

 

[chuckottawa]

Haven't posted for a while but I've been watching....

I've got a 2006 254 that I bought new. The electrical system really sucks and has since new but thats another story.... Right now the issue is overheating. The tractor starts and runs fine for quite a while when mowing. I've got a 60" chinese bushhog style mower deck and it has been running fine since I got the whole rig, until last year. I can mow for about half an hour and the temp keeps climbing slowly. When it hits 100C I shut down and let it cool or take the garden hose to the radiator til its back in the green. Last year the issue turned out to be the cap which wasn't sealing properly. It would allow water to leak out the overflow til the level dropped enough to start the temps rising. I replaced the cap last summer with a higher pressure unit and that seemed to work. Now I'm back at the same issue only I'm not losing water through a faulty cap....its just getting hot. I checked the thermostat when I replaced the cap and there wasn't one in it. I put in a 180deg thermostat and that seemed to help too. I checked it and it is still working. The tractor only has 175hours on it since new and has good oil pressure, starts easy and runs good. I'm wondering if the governor is allowing too much fuel into the system and making more power than the radiator can dissipate? I pulled the dipstick on the injection pump/governor and its full of fuel. I don't think thats proper as it had been running just fine prior to this with engine oil. I haven't had much mowing this year due to the drought in the midwest and no grass to mow. It was fine in the spring (the injection pump) but now its not.....I've had overheaters before and they usually get hot quick or else they run fine. This one takes a long time to get too hot and thats puzzling.
Any suggestions are appreciated.

Frank

Remove grid inside front grill to allow better air flow to the radiator,254 Foton stops overheating.It was poor design to block air flow with inside cover.