Synthetic winch line

[hochung]

Interesting info on hydraulic winches.

Michael,

is the MM hydraulic able to power out then?

and when you stop, the hydraulic pressure is holding the planetary gear in place? or is it some other mechanism? what if you shut off the engine? and no pump is working... does the winch hold the load? or will the load pull the winch line out?

 

[robert j. yates]

With all of the "improved" power steering pumps on the market for rock crawlers these days, a dedicated pump while nice for redundancy is not really a necessity IMO.

I have a AC Delco hydrobooster specified for a 1 ton Chevy truck fabricated into my Jeep and I run it with a Tommy Lee pump and high flow Tommy Lee steering box. I don't have any issues with the pump running both systems so I suspect that in a stockish truck, a hot rodded pump would be more than sufficient for a hydraulic winch.

 

[hochung]

Robert, you have a hydraulic winch there, so please educate me on this.

you are winching yourself up a hill. and let's say you stall and engine shuts off. or for whatever reason the hydraulic system gets shut down.

what happens then? will the winch hold the load? or will it let go?

 

[michaelgroves]

Hochung - yes, the MM hydraulic can power out. When the valves are closed, the winch can't turn, so again, yes, it will hold the load when stopped, against the hydraulic pressure, regardless of whether the engine is turning the pump. Also, it won't be subject to the pressure relief valve, as that's on the pump side of the valves, so theoretically, it will hold a bigger load than it will pull.

Just keep in mind, though, that no consumer winches should be used for any kind of lifting! All of them are built to a price, and to be as light as possible. Of course, some are much worse quality than others, but none of them is up to the standards of lifting equipment. The components are designed to be just within the rated pulling capacity of the winch to conserve weight and cost, with just enough margin to keep working until the warranty runs out!

It's ok to spool out under load (or use the winch to pull a load up a hill), but it then you should always have the load under control (able to brake by itself, or "tailed in/out" by an adequate second line and anchor, etc.)

The simplest way to think about this type of safety when using the winch, is to naturally assume that the winch or rigging will break at some point during the pull, and then to plan everything accordingly!

 

[michaelgroves]

Any vehicle with Hydraboost is likely to have the same issue. GM & Ford US diesel pick-up trucks come with this system. I think that Dodge's still use a vacuum pump, but no direct info on that.
Aftermarket vendor: http://www.hydratechbraking.com/
H-B, as it is sometimes referred to, is a good option for trucks with modified brakes. Makes for a much less demanding system design, i.e. it covers up most subtle system inadequecies, but it places more stress on the PS pump.

As has been said, a dedicated pump is the best idea, even if not easily integrated.

A stalled electric motor also gets really hot, really fast. Only way for that to happen that I can think of is very high current. Since there is a practical upper current limit there must also be a practical upper torque limit. I'm sure that still exceeds the winch's rating, but by how much would be hard to quantify w/o testing.

Interesting stuff on the H-B., thanks! I like the idea, in principle, since braking really doesn't require a lot of power - it should be easily within the capacity of a PS pump (esp. considering the little vacuum pumps which most diesels use!). But then yes, I'd definitely opt for a dedicated winch pump, rather than sharing three ways.

Regarding the upper limit on torque on an electric winch motor, I agree entirely - as soon as the winch slows down under load, the amperage starts climbing, and stall time is when it's most likely to burn out. I imagine the peak amperage and peak torque depend very much on the winch model and the individual electrical installation (battery type and condition, wire gauge and length, etc.) . Trouble is, any practical testing runs the risk of being an expensive test to destruction!

 

[robert j. yates]

Sorry if I wasn't clear...I run a Warn 9.5XP electric. I was simply speaking to the issue of the power steering pump and hydraulic winches. As I said, I am running some pretty serious hydraulics on my Jeep for the steering and brakes and from that, if one was to want to run a hydraulic winch, then there seems to be an aftermarket there thatwould reasonably support reliability and added performance.

That aside, I've only watched 2 hydraulics in action and they were both painfully slow. I didn't take a close look at them and nothing else with regard to your questions seems to ring a bell either. I personally would not ever run a hydraulic due to their slow speed so I have't really looked into the issues you speak about.

Robert, you have a hydraulic winch there, so please educate me on this.

you are winching yourself up a hill. and let's say you stall and engine shuts off. or for whatever reason the hydraulic system gets shut down.

what happens then? will the winch hold the load? or will it let go?