Just picked up this power unit, thought it was air start, I realized it's hydraulic start and am a little confused. I'm not sure where it gets its initial hydraulic power to start. It's got a hydo reservoir, an accumulator, and valve that control flow to the starter but I'm just not sure where to begin, should the accumulator be pressurized with air? The unit was a big compressor, afterall. Help!
It should have a pump on the accessory drive to pressurize the accumulator when the engine runs and a hand pump to "jump start" it if the pressure leaks off. IIRC, those accumulators were built with a piston to separate the oil and nitrogen. The hydraulic starter system is covered in most of the Detroit service manuals. Personally… I would just go electric.
Ok, this makes sense to me, thanks. There is this large hand pump next to the accumulator. I will probably try to get it going with the hydraulic system, but like you said I will probably take it off and go electric.
Once I worked on a tugboat that had a number of engines, including a 3-71 with a hydrostatic starter. The main engines (3600 HP) had big air starters. To build air, a compressor was powered by one of two 8-71, 150 KW gen sets. Those had air starters also. In the event all was dead, the 3-71 gen set could be hand pumped up to get it started to run the air compressor and get everything going.
When I worked in the Gulf, many of the cranes had hydraulic start. They were pathetic in warm weather and nearly impossible in cold weather. Had to have them or air start because of the natural gas being produced. Some have a pump on the engine to fill the accumulator and compress the nitrogen, but the pump is not needed because you can simply tap into the hydraulic system. If the crane had hydraulic cylinders for the boom, I used that circuit since it was easy to bring it up to near relief pressure. The accumulator should have a pressure gauge. Make sure the pressure is up before you shut off the engine!! The starter itself is a stack of warped washers running a worm gear. The company I worked for forbade ordering starting fluid so I bought it with my own wages and carried it for engines equipped with hydraulic start. Both Deutz and Detroit engines were equipped with them.
Have a Detroit V-71 manual with the operation of the Hydraulic Starter, both the Operations Manual and the Service Manual have sections on the Hydrostarter. If there is any interest I could scan and upload some pages. Not sure how different a 3-53 system would be compared to the V-71 series.
Thanks everyone, that puppy fired right up once I primed the fuel system, and pumped up that accumulator. Runs great, only 517 hours, its for sale if anyones interested!
I try attaching the pages out of the V-71 manual on the HydroStarter.
Oh man the nightmares are starting again!! Towboats on Alton pool and dealing with those with THOUSANDS of hours on them. Easy enough to rebuild but a slimy mess doing it.
Sorry about that! Would a coupon for hand-cleaner from Harbor Freight help? https://www.harborfreight.com/1-gallon-citrus-handcleaner-with-hand-pump-43222.html or https://www.harborfreight.com/45-lb-goop-hand-cleaner-40717.html
HAHAHA!! Just old memories these days what I do here non-issues. Not much would clean the DD stain from bilge stank that we got on us on The Pool. I swear would rather work the quarry over the tows most any day, could at least get away from it easily for a break.
Thanks, that was interesting. I like the idea of a manual starter for a marine application or back woods. A dead battery in that situation could be disaster. But with a manual start option, just a delay. A question about the pump though. Does it constantly relieve when the accumulator is full while running. Seems like it would heat the fluid and be a parasitic load. I didn't see a bypass valve.
Pumps were internally relieved back to tank, third line. Reservoir sufficient volume and flow low enough heat could be dissipated.
It was actually more of an unloader valve that kicked out at system pressure. Kind of like the accumulator charge valves on the old Cat loaders.
Essentially a Closed Center Hydraulics system.
Didn't the Huey helicopters of Vietnam era have a hand pump to pump up the closed loop nitrogen starter if they lost the pressure in the tank without a start? As I understood it took a long time by hand to recharge.