Water pump repairs for tractors Valmet 805 and MF 390
The water pump leaked on Volvo BM Valmet 805 (pre Valtra). I've taken the radiator aside and removed the cooler fan and the pulley. The separate thermostat housing is also taken apart and is there on the front weight frame.
I've removed the thermostat housing from the cylinder head and the water pump from the block.
The impeller has places for puller, but I'll press on the head of the shaft.
I used 4 bolts to pull that fan and pulley pole out of the shaft, wasn't very tight. On the left can be seen the "gossip hole" in which the leaking fluid came out.
Below the steel bars was a m8 long nut to press the shaft. Then we remove the locking ring and press the shaft out of the housing up this way. The bearing can't move the other direction.
The purchased pump overhaul kit and some parts taken off the pump. The kit is costing about 100 € and the whole new pump 300 €, prices at Valtra dealer. The gasket on the left didn't fit anywhere. The brass sleeve and O-rings are for joining the pump and the thermostat housing. When installing the pump to engine, I used glue on all surfaces besides the paper gaskets.
To remove the shaft from the impeller and the pump housing I used a press made of pump trolley and truck fork, which other spike is turned upside down. I pressed with a m16 bolt that fitted in the impeller center hole.
The axle seal was in pieces. It has spring loaded ceramic sealing faces.
The new axle seal was pressed in casing with a 1 1/4 inch pipe in that carpenter's bench. Middle of the seal there is a sleeve which keeps the box seal together and it needs support when the shaft is inserted. The spring in the seal allows the sleeve to move some millimeters. Before installing the seal I sank it in cooling fluid to make it wet. A real installer would probably first insert the shaft in case and after that install the seal with a special tool, that has support to the middle sleeve.
The shaft is pushed in to meet the middle sleeve, which is then supported by placing the impeller and extra disc under it. The disc is too thick, so I place some spacers under casing. Then we can try to press the shaft in without breaking the box seal. The final place of the sleeve can be checked through the "gossip hole", where the coolant leaked out.
The bearing assembly slided easily in pump casing. Used some grease on all surfaces.
At first I pressed the shaft in casing and impeller, so that the impeller found it's right place. Then the pulley flange was pressed on the shaft using a short pipe. A socket was supporting the shaft's down end. Couple of tin plates were as shims between the pipe and truck tine to make flange go straight.
In this Volvo BM Valmet 805 tractor the coolant rotates also in the adapter of the engine oil filter. The plug to drain engine block is also here. I renewed a short coolant hose in there too. I pulled the hose with two bale snare loops and got it where it should be.
I also dismantled an old Massey Ferguson 390 Perkins engine water pump trying the same tactics used in the 805 pump. The impeller was tight, I didn't dare to press harder. This pump didn't leak but bearings had big free play and I replaced the pump to make sure it don't break at worse moment. You can buy this kind of pump maybe with 100 € and repairing kit costs about 70, so they are usually not repaired, if not box seal could be purchased separately. The repair kit has also new impeller and there is no need to take the old one apart.
The pump has separate ordinary bearings and the shaft can be pressed out on pulley end. There's been grease between the bearings and it's gone grits with coolant and rust. The gossip hole is somewhat stuck, it's too small. Maybe cleaning the hole sometimes could make the bearings last longer. The impeller could at first be pressed inwards to make it move and outwards after cleaning and greasing the shaft end.
390 helps boots on for the spring duties.
Ready and eager for chopping some stubble.
Valmet worked fine at spring 2018.