I am definitely interested in more information, if both of you can give me the insights, and what you would do if you had do to it again...it would be great! (the more details you can give me the better, no one seems to know how to make this darn thing make a little bit faster!!!
My rig does have an A/C so if you can keep that in mind when making recomendations, i would love it! thanks alot!!
Ron:i guess you would need more like 15l/min so more like 13..15cm3 per revolution - at least these are the values required for MileMarker winches and I would believe that for others as well.
I also use single v-belt and it can transfer about 2kW power which is enough for 12000lbs winch to go at about 2m/min. I did some seroius winching and no problem with this single belt
Serious winching = 4 hours of winching through the mud hole with breaks just for relocating the hook to another tree
Hmm, something strange happening here to the quotes. Never mind.
Well, some more info then
I agree on what WojtekSz says about pump capacity. But at the time I build my setup I was not aware about the amount of power I could transfer through the A/C clutch. I therefore choosed a setup in which I rather went for speed than for torque.
By choosing a set-up where I need 2000 to 3000 RPM (engine!) to get the needed volume I wanted to avoid to have to transfer a large torque through the clutch.
I now know that a larger pump (indeed WojtekSz
) like 10-15 cm3 will work better. This way the engine can turn slightly above idle and you would still have the needed flow rate to have normal winch speed.
Another thing I took into account when I choosed for my set-up was that, by altering the engine-speed I also could regulate the winch speed. Nice idea but there is hardly any need for this I found afterwards.
So my advise now is: use a larger pump than I did.
As you see I've put three photos in this message.
The drawing is about the connection between the pump and the A/C clutch. I had to keep in mind that this kind of pump does not allow a pulley to be bolted to the pumpshaft and to drive it by a belt. No radial forces are allowed. All you are allowed is to turn the shaft. Sounds a bit strange but this is because this pump has no real bearings. For me that was no real problem because I was going to use that A/C clutch that has a housing and bearings by itself.
If yo look at the drawing ( sizes are just applicable to my setup!) you can see the blue part. This is the housing for the A/C clutch and carries the forces excerted by the V belt to the crankshaft.
The Red part is a kind of 'transfer'. It is sitting inbetween the A/C housing and pump-body (the red arrow on the photo with the view on the pumpassembly)
In there are two small bearings, guiding a bushing that has teeth at the inside and can slide (don't know the english expression for it, but it's similar to the sliding part of a drive shaft). This part connects the pumpshaft to the A/C centre shaft, without transferring any radial forcesbut allowing some axial play.
At very left side (yellow, I hope it's visible) you then find the schematic of the pump shaft.
The A/C clutch is engaged by energizing it and only then the pump will run.
The hydraulic fluid then passes a pressure regulater (see picture with the squarish part) because the pump can deliver more than twice the allowed pressure. The regulator is is calibrated to the max allowable pressure.
After this the fluid gets to the valves of the winch, electrically controlled for in and out. After the winchmotor, the fluid is pressureless and enters a cooler that sits in front of the engineradiator. After the cooler it returns to the pump. In this returnline there is a T-connection that connects to a small reservoir (about the same size as the power steering reservoir)
With this setup I've been winching under fairly harsh conditions.
Apart from the winch speed (slow) I'm very happy with the setup.
Three examples:
1. A Landrover Discovery buried in a ditch in the mud, halfway the doors. The owner was able to find a connection point where he could hook up the cable by feel. I was afraid to winch ( the cruiser connecte at the rear to the guardrail of a freeway) to full capacity as I was afraid of damaging the Disco (10,500 lbs pulling force!) But he wanted to have it that way. So I put strain on the cable and then waited until the Disco gave a bit, put strain on it, waited etc. Took almost two hours to move it for about two meters and free it from the suction of the mud.
2. Tunesian desert (Sahara) A Nissan Patrol, stuck in sand inbetween two dunes. Flat on it's belly. Took about an hour of hard wiching. No problem. No overheat.
3. Moroccan desert (Sahara) This time I got stuck myself in a very deep pit inbetween dunes. Sand was so soft the rig was flat on its belly, could not get it on top of the sand despite sandladders. Sand was like water. Had to winch over a distance of about 30 meters under hot (35deg celcius) conditions. Here the enige temp went up because of poor airflow after about an hour of winching but the hydraulics were okay.
The only way to have a fixpoint was to put one of the other rigs (an 80) just over the ridge of the dune. Standing on the ridge didn't work All I did then was just drag it towards me instead of winching myself out.
It took about two hours of hard work but we managed. If I had been on my own I never could have freed my rig. A ground anchor didn't work.
If your A/C in in the way and you cannot accomodate a separate pump then the only option is to have a larger PS pump. Or....and that would be MY option: have a PTO-driven pump.
Disadvantage:1. Costs (and here in Europe it's hard to get a PTO-gear) 2. You have to be in gear and to make sure you don't over-rev the pump. It then is also a bit complex to have power to the wheels and winching. The moment you press the clutch you also loose your winch. To winch without spinning wheels the transfer must be in Neutral.
