1970s Mustang Owatonna Mfg
Co OMC 440/441 Skid Steer
My son, Dave, rescued this old (1970s?) Mustang (440?) skid steer loader from being scrapped, and brought it up on his amazing crane truck when visiting with his two gorgeous kids over Easter.
It seemed the engine had seized, as the starter motor simply locked when trying to start the Perkins 4.108 4-cylinder diesel. For the price (just the diesel cost getting it up here) I didn't mind, as a Perkins is always rebuildable.
However, after a bit of tinkering, I realised the engine locked when turned in the direction it runs, but could be hand-cranked backwards. A classic case of hydraulic lock, which is cured simply by the reverse rotation until the offending fluid (water, oil or diesel fuel) was ejected back through the inlet valve. I'm still not sure what the fluid was, but I suspect water, as the air pre-filter had a rusted through cover, and in heavy rain could have caused some water to flow down the air intake and into the open intake valve.
Whatever it was, the engine then cranked evenly on the starter motor, indicating all 4 compressions were there, and quite equal. So I simply cracked the injectors to bleed them of air, and within minutes the good old Perkins rattled into life (attached video).
I quickly shut it down, and checked the radiator and found it leaked like a sieve at a certain level. A pressure test at the best radiator place I've ever used (Paul at Chris O'Beirn Radiators in Ballarat) confirmed my suspicions. The core was cactus, thanks to many years sitting inactive with the radiator partially filled, causing the tubes at the water level to simply corrode away. $1000 for a new core. So, raid my parts bins. I had several Mercedes W123 radiators, but they were just fractionally too large to fit. Enter the original Holden radiator from Dolph, our much-loved Bedford CF camper. Just the right size. Raiding the scrap metal pile out the back of the shed provided the angle iron to fashion a custom frame. Done!
