Re: Are hvfb and ahvfb motors interchangeable?
I gave you some incorrect info in a previous post. Here are the differences hydraulicly between three different 4000 series tractors.
A basic 4000 series, no power steering, pump spec is 8 GPM @ 0 PSI @ 3,000RPM. Belt driven mower deck and snow blower.
A 4000 series with power steering , pump spec is 9.5 GPM @ 0 PSI @ 3,000 RPM. There is a flow divider that splits the 9.5 GPM output so some of it goes to the power steering pump. Belt driven mower deck and snow blower.
A 4100 series tractor has a two section pump. The front section spec is 9.5 GPM @ 0 PSI @ 3,000 RPM. The rear section spec is 2.25 GPM @ 0 PSI @ 3,000 RPM. The rear section is for the power steering only.
All attachments for 4100 series tractors are hydraulicly driven, there is no room on the front of the engine for an electric clutch as is found on 4000 and 4000PS tractors.
The travel circuit on a 4000 and 4000PS has a relief setting spec of 2,100 PSI.
There is a system relief valve on a 4100 and has a relief setting spec of 2,800 PSI.
The 3100 and 4100 series tractors were produced for about 2 years, 92-93 if I'm not mistaken, very limited production. The 3100D and 4100D were diesel engine powered and had similar hydraulic systems to the Onan gasoline powered tractors.
Bob MacGregor in CT