Yanmar 1500

[Kyhunter42]

Hello everyone,
This is my first post and I'm sure I will have many more after this one. I recently bought a Yanmar 1500 and it is my first tractor. It came with a Woods RM59 finish mower and a 4' box blade. The guy I bought it from could tell a lot about it and I have been able to use this site to figure out a couple of things about my tractor. I will be using my tractor to maintain 350' of gravel driveway, mowing 2.5 ac field in front of my house, and to do some leveling of my yard (removing ruts from where crops were planted many years ago).

I have noticed that my tractor overheats while I am mowing. It only takes about 15 minutes for the light to come on. The guy I have bought it from said he thought it might need a Radiator cap. I ordered a new cap and I plan on flushing the coolant and ensuring it has the correct mixture. Hopefully this will solve the issue. I have seen aftermarket water pumps for these tractors and I was wondering if they are worth buying? Do anyone have any experience with these?

I also had a question about mowing with my Woods RM59. The guy I bought it from said that I should use the mower in the #2 PTO. I was able to find what the PTO rpm are for my tractor, but I am not sure what RPM the mower needs to be run at? Does anyone know? I've tried the Woods website and they do not have the manual for this mower listed.

Thanks,

Tim

 

[winston1]

Unless your 1500 has had it added you do not have a water pump. Here are instrucitons for it. Yanmar Tractor Overheating

Your mower rpm should be 540. You should use #1 pto gear with tractor at 2200 or so rpm.

 

[Kyhunter42]

I guess I should have asked it a little different. I was wanting to know if anyone had experience with the water pump conversion kit:
Yanmar Tractor Parts: WATER PUMP CONVERSION KIT-YM1500

 

[Kyhunter42]

Thanks for the info on the PTO and the mower. I wasn't sure about that.

 

[California]

Overheating in 2012 in a 1970's tractor would point to a clogged radiator. Take it off and have a professional shop boil it out.

Spending money on ordinary maintenance is better than spending to monitor the unresolved problem (temperature gauge) or patching around it (adding a water pump. Yanmar designed this to not need a water pump).

After the cooling system is restored to original spec, the engine should be able to run continuous at full output and never overheat. If you aren't powering a ditch pump or something like that with heavy continuous load, you'll never stress it that hard.

You might first try radiator cleanout chemicals but I don't think that will be sufficient to open the clogged tubes in the radiator. That might help to clean the block in preparation for the professionally-cleaned radiator.

 

[Kyhunter42]

I picked up a 13lb radiator cap today and replaced the old one. The old one was missing the gasket at the top. I mowed with it in 7th gear and in the #1 PTO for about 2 hrs with no problems. Hopefully that fixed the overheating.

 

[amayakobayashi]

Really Yanmar 1500 is best tractor i see in my life in heavy equipment category. Many tractors i found but Yanmar is excellent.

 

[Neat 1500]

wont hurt to give it a good flush out anyway and add 25/75 coolant to water. that way you know its right. i can run mine flat out all day in all conditions and it never runs hot.

 

[clemsonfor]

Good advice so far. I would make sure the radiator is clean and clear, that includes the inside and outside. You sometimes have to remove it to get all the fluff and seeds out of it. But that cap could and most likely was a problem but i dont think thats entirely the cause as they dont really get worked hard enough to overheat at atmospheric pressure i dont think in 15 mins. Is it possible that someone overheated it prior to you getting it if it overheats that fast? And yes i will second the 1st gear on the pto equaling 540 rpms. and keep it in the 2000rpm range give or take, but yes 2200 is the correct spot.

 

[Kyhunter42]

I ran the tractor for 8hrs today with no problem. I'm going flush the radiator Monday when I get home.

 

[driftwood]

Ive got a 1500, After a new radiator it was still running warm (around 215) I installed the waterpump kit from Hoye. The directions are pretty bad, but the job an easy one. Also the belt was 1 inch too long. I just ran to the parts store & got the right one for about 8 bucks. The tractor runs about 190 on a warm day now. Wally

 

[Neat 1500]

Ive got a 1500, After a new radiator it was still running warm (around 215) I installed the waterpump kit from Hoye. The directions are pretty bad, but the job an easy one. Also the belt was 1 inch too long. I just ran to the parts store & got the right one for about 8 bucks. The tractor runs about 190 on a warm day now. Wally

thats good that it doesnt overheat now but the underlying problem is still there. they were designed not to have a water pump and not overheat. mine never runs hot even on the hottest of days working flat out. i think you need to keep looking for the cause IMHO

 

[clemsonfor]

I agree with Neat. Your fine now but as that radiator gets clogged more the temp will slowly start rising again. Im guessing your radiator is just junked up internally from years of use.

 

[kencunningham]

I believe if the mixture of anitfreeze is not correct then that changes the specific gravity, and that affects the convection current of the fluid to create a flow thru the radiator. Of course if you put a pump in it , then its a moot point.

 

[clemsonfor]

Ken your probly on the right track. Thats why a previous member said to drain it and make sure its only 25% antifreeze in the water. This i think is the max that yanmar wanted in the fluid.

 

[careyo63]

I run store bought 50/50 in my 2000 which has a water pump. Since you put the pump converstion on you 1500 doubtful 25% is the problem them. Of course IMO. My guess is the Radiator still has or developed another problem FWTW.

 

[Kyhunter42]

I flushed my radiator today and refilled it with the correct solution of 25% antifreeze. The fluid that came out was pretty nasty and there was a distinct difference in the 25% mixture I put in and what it had in it when I bought it. I believe the previous owner was using 50/50 mix.

Problems I found:
1. Bad radiator cap
2. Improper mixture of antifreeze
3. Gunk inside the radiator

I corrected all of those issues and it seems to be running fine without overheating. I mowed thick grass for 5 hours yesterday without an issue. Hopefully this has taken care of the problem. If it does overheat again what is the next step? Send the radiator to a shop to get it cleaned? Replace the radiator?

 

[careyo63]

The low mix is for the Thermal Siphon and "no more than 25%" here's a good article you can read up on. I'd almost put money on it that it was the Dirty Radiator.
Yanmar Tractor Overheating

 

[284 International]

Make sure to carefully clean the outside of the radiator, too. Dirt, chaff, wasp nests, and all sorts of other things can block the passage of air through the fins. Making sure the fins are clear really helps, and should be a normal aspect of pre-use inspection, I think.

 

[clemsonfor]

If you have a water pump you can use 100% antifreeze and not see a difference. The 25% is for the Thermosiphon system to work like 284 mentions. Something about the water moving in the system from the cool radiator to the warm engine.

If your still overheating, take it to a radiator shop and have them "rod" it out. It will work like a new radiator once they professionally clean it.