Owatonna (mustang) 330 24hp motor swap with 20 B&S vanguard motor.

[HEO Retired]

I obtained an old Owatonna (mustang) 330 skidster in exchange for some mechanical work. It has the ancient Onan NHC 24 HP motor in it. Come to find out it has 0 compression in one cylinder and 80 psi in the other. This motor is way outdated and parts are spendy as heck. I have a line on a B&S 20 hp vanguard motor that runs. Will the 20 run this skidster efficiently w/o constantly wanting to or instantly dying as soon as you work the hydraulics under any load . My thoughts are.... It's a big boat anchor if it's not running. Even if under powered I can atleast use it a lil bit. Has anyone swapped motors using less HP motor? Any advice on this engine swap thru experience is muchly appreciated. Thanks

 

[Steve Frazier]

I can't answer your question but I can tell you I've had very good experience with the Vanguard engine. The difference between a 20 and 22HP engine isn't noticeable to me so I'm not sure your case will be much different.

 

[willie59]

Well, 4 less HP is still better than a boat anchor. Whaddya got to lose?

 

[Delmer]

The only issue I'd see is if the B&S is rated at a faster speed than the old Onan. If the Onan was a lower speed engine, then the torque will be much greater to get 24hp at 2,000rpm than 20hp at 3,600rpm. I don't know the old onan, shouldn't be too hard to find that rating.

 

[Welder Dave]

Yeah, I think a lot of Onans ran at lower RPMs than most other engines, the same with Wisconsin engines. Not sure what RPM Vanguards run at though. If the Vanguard runs higher RPM would be OK if the pumps can handle it.

 

[Old Doug]

I don't know how it would work but if the machine is in good shape and you have a use for it I would look for a different engine . I had used/run a lot of skid steers but wasn't sure what one was worth to me. I bought a cheap running skid steer and now know how much I use it I have a lot different outlook on what its worth.