Yanmar 2500 frankensteined

[California]

old starters use a solenoid and turns at 1.2Kw of power, the newer technology is a OSGR starter and turns at 2.0Kw of power. ... If you have a very old and tired starter, then upgrade.
View attachment 821835

That starter or one very near the same is what I put on the YM240 to replace the bad amateur rebuilt I found when I got the tractor. It was under $100.

With the higher amperage and the gearing, it cranks much faster, so I expect this would even start a worn out tractor that doesn't have spec compression.

 

[careyo63]

I've mentioned Before that I always use the decompression. My rule of thumb the oil light goes out let it the decompression handle go and let it rip!! Easier on the starter also. My old Org. starter has the light off by the count of 5 one thousands. Hot,Cold, Rain or shine. Few yrs. back is how I knew the org. battery of 10 yrs. was going bad. It would show 12V. but the CCA, Cold Cranking Amps was real low when I had it checked. Replaced it and went up from 550cca. to 850cca. and that made big a difference. When its hit it's been super quick firing up ever since. I was actually in mine before having to get it rebuilt and put a ghetto rig on it. Shop mentioned it they could tell. There wasn't anything left of the brushes I turned around. Not much doubt it'll be rebuildable again if need be.

 

[Uncle_Charlie]

There's been no update for some time as I just didn't have anything to update. This past week, the tractor is finally running correctly and not showing any sign of overheating. As a reminder, the PO said he thought the engine was overheating but he wasn't sure. When I put the tractor into use, it was filling the overflow tank within a few minutes, and boiling coolant in the block after half an hour of operation. Replacing the head gasket did solve the matter of filling the overflow tank as the cooling system was no longer pressurized with combustion gases. However, it was still overheating (meaning boiling in the block). Bear in mind, this was with a new water pump, radiator, hoses, and belt. I went back to the exploded parts diagram earlier in this thread and found the answer. The water pump has two pipes on it. One goes to the lower radiator hose, the other goes to a bypass hose. They are the same size and right next to each other. You can probably see where this is going. I had the hoses on the wrong pipes. Effectively, water from the pump was pumped right back into the block, never making it to the radiator. This has been corrected now.

I ran the tractor for the better part of a day in 90 degree heat and another partial day in 75 degree heat. It never pumped anything into the overflow tank or sounded like it was boiling coolant in the block. How this engine took as much abuse as it has and can still run is beyond me. Now that everything is correct, it is running at normal temperatures and not losing coolant. I would have expected the head or block to be warped, but there's no evidence of it.

The tractor still needs some attention, but now I'm comfortable running it.

Thank you to all who helped.

 

[ponytug]

"Built Yanmar tough".

I think that Yanmar tractors were designed to be used and perhaps overused in lots of low resource settings.

The old Timex tagline comes to mind, too.

Congratulations on getting the hoses worked out!

All the best,

Peter