For a long time now, I have been having trouble with my 1020 Massey Hydro. Has been making a lot of noise and got to the point that it only has about half power after it gets warmed up.
Last weekend I decided to tear into it. What I found was where the cylinder block wears against the valve plate there were score marks which was allowing the oil to seep from one hole into the next instead of flowing through the valve body as intended. I was told by a guy at a machine shop that works on these type pumps and motors that this is what I would be looking for. He said that even the slightest scoring would cause extreme power loss. Operating pressure is 3850 psi.
It's a KAYABY Hydro unit and IMO parts are very high priced. Massey will not sell only the parts that are bad. They only sell parts in assemblies. Example, the pump assembly $ 1200.00. The motor assembly, $850.00
I did it for less than $300.00. /forums/images/graemlins/laugh.gif I was able to re-surface the faces of cylinder blocks and valve plates myself by spending around 5 - 6 hours of sanding by hand. I used 400 & 600 grit wet sand paper on a hard flat surface, keeping it flooded with oil. I used up about 8 sheets of each grit, but the faces look very good now, compared to what I started out with.
Now it has full power and is quieter than I can ever remember. Time will be the ultimate test, but I'm happy now.
Here are some photos of what I did. The cylinder blocks and valve plates are only 3" dia. Some of the photos were extreme close ups. Also a few pics of the tractor halves and pile of parts.
If this works http://tinyurl.com/qej5a
Last weekend I decided to tear into it. What I found was where the cylinder block wears against the valve plate there were score marks which was allowing the oil to seep from one hole into the next instead of flowing through the valve body as intended. I was told by a guy at a machine shop that works on these type pumps and motors that this is what I would be looking for. He said that even the slightest scoring would cause extreme power loss. Operating pressure is 3850 psi.
It's a KAYABY Hydro unit and IMO parts are very high priced. Massey will not sell only the parts that are bad. They only sell parts in assemblies. Example, the pump assembly $ 1200.00. The motor assembly, $850.00
I did it for less than $300.00. /forums/images/graemlins/laugh.gif I was able to re-surface the faces of cylinder blocks and valve plates myself by spending around 5 - 6 hours of sanding by hand. I used 400 & 600 grit wet sand paper on a hard flat surface, keeping it flooded with oil. I used up about 8 sheets of each grit, but the faces look very good now, compared to what I started out with.
Now it has full power and is quieter than I can ever remember. Time will be the ultimate test, but I'm happy now.
Here are some photos of what I did. The cylinder blocks and valve plates are only 3" dia. Some of the photos were extreme close ups. Also a few pics of the tractor halves and pile of parts.
If this works http://tinyurl.com/qej5a
