The Classic Machinery Network

Does anyone know why the cooling fan in the Ransomes T51D is mounted so that is blowing air into the Radiator. I thought cooling fans draw the cooler air from the radiator onto the engine?

see attached pictures of the Ransomes T51D engine compartment. If you were standing at the rear of the radiator in the picture, the cooling fan rotates in a clock-wise direction.

I also attached a picture of the same engine as what is in the Ransomes T51D (Kubota v2203) that i found on the web with a fan mounted and in that picture, the cooling fan blades are in the direction i would expect.

I suspect that it may just be the case that somebody has had the fan off in the past and fitted it back on backwards? Does the engine overheat? You are quite right though the fan should draw cooling air through the radiator, daft question if you stood in front of the radiator and revved the balls of the engine can you feel it blowing air through?

Jeremy

Thanks Jeremy for responding. Well i had same thought but if u reverse a fan blade it will still be in same angled orientation but the curve of the blade will be reversed. I would need to get a fan blade that has the blades mounted in the opposite direction to mine to see if it helps. Your question is not daft at all .. if i rev the engine, the cooling fan is blowing very little air onto the engine and instead it blows air into the radiator and the air comes out at the top cavity between the radiator and the oil cooler. (the radiator is mounted at the rear of the mower and next to it is the oil cooler and then the engine as u might see in the photos). When the hood is on the machine, there is really no place for the air flow coming up between the radiator and the oil cooler to go though. What happens is that grass gets blown into this cavity between the radiator and the oil cooler which doesn't improve cooling as u can imagine. I think what happens is that a vacuum is created around the engine and grass is sucked up from under the engine compartment and then blown into the radiator by the fan. My feeling is that it could have been a better design to have the cooling fan blowing away from the radiator and onto the engine as it might keep grass particles blown away from the Rad/oil cooler cavity. There is prob lesser chance of grass particles being sucked in from the rear of the machine as it furthest away from the cutting decks.

Billy just looking at your photos again I see that the fan also draws or blows air through an additional cooler which I assume is an oil cooler? In the last photo it also appears (I could be wrong on this) that the edges of the fan blades look damaged? Is that the case? Again I wonder if somebody has fitted a secondhand fan in past times and it is not the correct fan, do you have anyway to confirm the correct direction of airflow with the manufacturer?

Jeremy

Billy.
Might be wrong here (often am) but don't those type of mowers blow the air out of the engine compartment to save sucking cuttings through the rads from the outside and blocking them.
Norm.

Hi Jeremy/Norm

so from any pictures i see of the T51D on the www, the fan is pulling air from the engine side in towards the oil cooler and radiator same as mine. Also I notice many have that slight damage on the outside of the fan blades for some strange reason. yes the air flow is in direction of the arrows below.

engine -> cooling fan -> oil cooler -> radiator

Norm, i have to take off the hood because the space between the oil cooler and radiator gets completely full of grass if the hood is on the machine. I think it draws the grass (specially if grass is dry), up from the bottom of the engine (it would be difficult to block off) and the grass gets blown into the cavity between the cooler and the radiator. When i take the hood off, and start and rev the engine, she will blow grass up in the air from the cavity between the oil cooler and the radiator and then it will stay clear thereafter, while the hood is left off.

Jeremy Rowland wrote:I suspect that it may just be the case that somebody has had the fan off in the past and fitted it back on backwards? Does the engine overheat? You are quite right though the fan should draw cooling air through the radiator, daft question if you stood in front of the radiator and revved the balls of the engine can you feel it blowing air through?

Jeremy

Hi Jeremy it's not possible to reverse the fan air flow by fitting it wrongly.
We always had this argument with the fans on the dozers. If you wanted to fit a fan that blew out away from the engine you had to fit a dedicated "pusher fan." as opposed to a "sucker fan."
My operators clamored for a change of fan summer and winter, it provided the only heating, (sucker fan), or air-con, (pusher fan), in the cab in those days.

Correct Fowler Man, reversing a fan blade only changes the curvature of the blade but not the Direction. I ordered a "Pulling" fan so i will try that and see if it is better than the current arrangement. I was thinking if i have any issues with grass debris coming up up from the engine compartment, I might try rock wool to stuff those lower engine spaces where the debris could get in.

Thanks Fred you are correct as ever I wonder if the machine had the wrong fan fitted on it then?

Jeremy

Hi Jeremy

No, it was by design that Ransomes fitted a "pusher" fan ie it pushed air from the engine towards the oil cooler and radiator. The thinking was that it keeps the system cleaner of debris. Im not convinced this arrangement worked out though, as plenty debris gets stuffed in the space between the oil cooler and radiator, plus the engine has a tendency to run hotter. There are countless tales of these older Ransomes mowers running hot and people having to leave the hoods open to let the system cool down. I am going to try a puller fan to see what it does and i'll let you know any differences i see.