Foton heating quickly

[succor]

Hey everyone, Just got my rad in and new antifreeze in on my 25 hp foton; similar to jinma. Boy the rad was clogged so the airflow is much better. My question now is I ran the tractor at a fast idle till it hit 80C and it stayed. What I noticed is it seems like the temp rises quickly as it was warming up, so I was feeling the top and bottom of the rad; big difference! The top of the rad is hot, so is the fluid inside with the rad cap off, and the bottom of the rad is cold still, the bottom rad hose is cool for the most part except for a bit of warmth near the block but not much. So I'm wondering, is the water pump working?? Should the bottom of the rad be warm a little too to indicate that water is flowing through the rad or is this normal to start. I only ran the engine at 1600 rpm for about 10 min. Fan is working good, belt tension is tight.

 

[Bob Rooks]

ΔT's should only be about 15°F @ 80°C. You have coolant flow issues. Stuck thermostat (only bypass coolant getting to top tank), or coolant pump failed (impeller). Your coolant pump could also be air bound, make sure there is no air in the system.

 

[succor]

Where is the thermostat located? Is it part of the pump? I know when I washed out the rad, there was some rust coming out but I probably didn't wash it enough. I'm wondering If these 2 parts check out to do a complete system flush. Is there a procedure on doing a system flush on these units. Is there a recommended flush cleaner to use through the engine?

thanks

 

[succor]

Also what is 15F when tractor is @ 80C. Do you mean thermostat?

 

[Bob Rooks]

Where is the thermostat located? Is it part of the pump?

What?? I'm hoping that one of the members with more knowledge of Foton tractors will jump in here.

 

[Bob Rooks]

Also what is 15F when tractor is @ 80C. Do you mean thermostat?

That is the temperature difference between the top tank and the bottom tank.
Delta-T. If the coolant going into the engine is too cold there will be thermal shock on the liners, the thermostat bypass helps this.

 

[Transit]

I would suspect that if you have a T-stat or pump issue at this point you would still have a boil over / overheat problem.
At 80 Deg C = 176 Deg F [deg C X 1.8 + 32 = Deg F], you are way, way in the green. At that temperature you may safely run the engine with the radiator cap off and you will see the flow start stop as the T-stat opens and closes. Slowly release the cap to vent any pressure, better yet, remove the cap when the engine is cold.

What you are observing is that the radiator is rejecting heat and cooling the water to temperature of the sounding air. The air temperature is the limiting factor for cooling, cannot go below that temperature. The radiator has reserve cooling capacity to compensate for higher air temperatures and for when you are working the engine harder.

If you suspect the engine is air bound, park the tractor on a steep hill with the radiator at the hi point, as the coolant flows through the engine it will drag any trapped air with it. Also consider installing a coolant recovery kit, $ 10.
What you MUST work on, is keeping the radiator clean, less air drawn from under the tractor with all the crud and more air from up top. You surely need to have a filter in front of the radiator. The T-stat is located as in a car, on the engine where the upper hose connects to the engine. But first burp any trapped air and get a coolant recovery kit. :thumbsup:

 

[succor]

Thanks for the tips, now get this. I hooked up my 6 foot finish mower and spent about 1.5 hours cutting grass to give this a test. I revved up to about 1900 rpm (higher than I usually go) and the temp gauge ran steady at 82C! No battery mod or air intake mod; just a cleaned rad! What a difference that makes. The hoses were warm and relative tight with pressure, so it must be pumping through to hold that temp. steady. I also added window screen as per other tips on this forum in front of the rad and just cleaned it(much easier). I also purchased like you guys said a coolant recovery overflow for $10 from partsource and I'm going to mount this. I still am going to add a piece of suction hose to the intake of the air canister and reroute this away from the rad to aid a bit more in cooling.

Thanks everyone

 

[Transit]

1,900 rpm may be a bit slow; most tractors need 2,100-2,200 rpm for a 540 rpm at the PTO. Be careful not to LUG the engine which will push the temperature up.

 

[Bob Rooks]

1,900 rpm may be a bit slow; most tractors need 2,100-2,200 rpm for a 540 rpm at the PTO. Be careful not to LUG the engine which will push the temperature up.

Approx 1,750 engine r/m will give you 540 r/m PTO, provided the selector is in the 540 position:
Chinese Tractor Owners Association - CTOA Forums - Tractor/Dozer Engines - PTO RPM

 

[greg_g]

T I revved up to about 1900 rpm

Based upon other Chinese tractors I've owned/operated, 1900 does sound a bit low for PTO operation. But it varies from engine to engine, so might actually be in the ballpark - for your FOTON. To be sure though, look for a green mark on your tachometer. That's where you should set the engine speed when you're using PTO powered implements.

//greg//

 

[succor]

Oh I didn't notice the green mark on the tach, I will check. The engine is a 3 cylinder mitsubishi engine.

Thanks

 

[Diamondpilot]

On my Jinma 254/284 I have a green mark on the tach for pto operation. Its about 2200 rpm and my red line is somewhere around 2500 rpm. Like others have said do not lug the engine, run it where it was designed to be ran.

Chris

 

[succor]

Hey thanks, I looked and mine does not have the mark, silly eh. BUt based on what I'm reading and the engines are similar and I can probably run this at 2200 rpm. Much more power at this RPM and still runs nice and cool with the rad cleaned!

 

[Transit]

Approx 1,750 engine r/m will give you 540 r/m PTO, provided the selector is in the 540 position:
Chinese Tractor Owners Association - CTOA Forums - Tractor/Dozer Engines - PTO RPM

Bob, the only way to know for sure is to measure the revs with a teach. Set the engine to give 540 rpm at the PTO and measure the revs at the engine pulley. My PTO at 540 = 2150 engine rpm no load, make that 2200 under load. 1,750 rpm = maximum torque for my engine from the engine charts.

 

[Bob Rooks]

That's what I did. Check the link. Used a photo tach on my PTO & compared to tractor tach. I have a two speed PTO & TY395 engine. Wheeled tractors may differ somewhat.

 

[Transit]

Yeah, the same here, the tractor/dozer tranny most likely has different ratios.