Jump to content

H14W hydro install & calculations


Recommended Posts

Since I've ticked a few little jobs off the list for the 109 the next big one is to fit the H14W hydro setup that's been sat in my garden for far too long.

I have read Ian's rather excellent fast winch build thread and the H14W Manual PDF which give me the following info cut-n-pasted into Ian's calculations:


Continuous Flow ?

Max Flow ?

Continuous Pressure ?

Max Pressure 2500psi (that's what the PRV is set at anyway)

Continuous Shaft RPM ?

Max Shaft RPM ?

Max Torque ?


Capacity per Revolution 22.84cc (33.6L/min @1500rpm)

Min RPM ?

Nominal RPM 1500 (33.6L/min)

Max RPM ?

Max Pressure 2500psi (that's what the PRV is set at anyway)

Drum is 88mm / 3.46" diameter (1st layer) so 1 RPM of the drum is 10.88".

The worm drive is 48:1 (compared to the MileMarker 6:1) so the motor can be less torquey but needs to spin much faster. Also there's no need for a PRV as the worm drive is irreversible.

Since I don't know all the motor specs I can't say what the max line speed would be, only what Superwinch quote - 8m/min or 26.25ft/min on the 1st layer, 14m/min 46ft/min on the outer layer, which seems to be within the realms of respectability if not super-speedy. Having never compared known line speeds in real-life situations (Jez's Type-R aside) it's difficult to judge if more speed would be desirable.

As Ian points out in yet another excellent tech post, true drive assist speed is a rather excessive 200ft/min :o which is outside the realms of practicality. Since I am aiming for proportional control with spool valves rather than on/off with solenoids, having extra capacity and throttling back a bit seems preferable to running out of puff.

I guess the cheap answer is to run with the stock setup and see how it performs, but I can't help but wonder before getting the spanners out if it's worth tweaking things - I have a box of hydraulic pumps, including tandem ones, in the garden gathering dust so the opportunity to up the flow for no money is there.

Link to comment
Share on other sites

Also there's no need for a PRV as the worm drive is irreversible.

Confused :huh: ... Not sure how the PRV is related to the worm drive being irreversable?- which incidentally I am not sure is the case??- Certainly a Superwinch husky will run backwards as it were in the right (or wrong!) circumstances- do you mean an overcentre valve which would hold the load if a pipe failed? PRV should only relieve excess pressure if the set pressure is exceeded- though it doesn't appear that you pump can do so in this case.

I feel a suitably technical reply coming on from BBC as well! Are the line speed figures you quote for the winch the max figures as quoted by the manufacturer?


Link to comment
Share on other sites

El Fridge,

You still need a PRV to protect against excess pump pressure , but you may not need an OCV (over centre valve) ............. but I would fit one anyway and they are only £50ish................. it stop the potential for over run whislt winching out a heavy load....

What / who is the manufactuer of the motor ? ................... there should be a plate on the motor giving the detail ................... if not, then I could give superwinch a call (they are local to me - Tavistock) and see what info can be gleaned ................

If we can find out the absolute manufacturers specs, then the numbers are easy ............ ;)



Link to comment
Share on other sites

I meant OCV :rolleyes: is it Friday yet? :unsure:

Ian - I will have a looky see if I can see a spec/manufacturer on the motor. My initial thoughts are to replace the pump with one that's happy to 2500rpm to gain a bit of flexibility, and replace the motor with a faster one, or at least one that won't mind going faster.

Link to comment
Share on other sites

Ian is spot on re PRV and OCV, I would strongly suggest you fit both and the OCV as close to the winch as poss.

Superwinch have had a range of suppliers for motors over the years and a selection of flow rates too, I have amassed a large file of uslees info on this sort of thing - being a bit sad :lol:


Link to comment
Share on other sites

I asked superwinch what motor they use on the direct coupled version of the H14 - the one with the small aluminium bellhousing that bolts the motor direct to the winch input. They advised that it is a Parker Low speed, high torque TB series motor. To be exact they quoted a TB0130AS100LAAY. I think there is a typo in this somewhere though as the code does not quite match the Parker product literature I have. How ever you can not get more than a few hundred rpm out of them - in other words far to slow.

Suggest that if you want drive assist with a reasonable pull (say 8000lbs), that you calc the winch drum power/torque you will need. By the time you factor in the worm box efficency, motor efficency, pump efficency, piping friction losses, filter pressure drops, valve block pressure drops, etc you will discover that in low 1st at say 1000 rpm that your engine does not develop enough power to pull 8000LBs. Rev the engine to get more power and you will be trying to pull 8000LB at a rediculous speed for that kind of loading and the power required at the winch has also gone up.

The outcome is that to get winch assist you must drop the vehicle gearing considerably. I am aiming for a 152:1 crawl ratio.

The next problem is you need a pump with a good combination of torque capacity and high speed.... £££££ and most hydraulic companies I talked to said it could not be done. I belive it can - but I have not run yet..... Picture below is my H14 with a custom alumminium bellhousing and high speed pump - the job is still in progress as the lack of bolting to hold the bellhousing on will show. I still have the internal coupling between the pump and worm shaft to manufacture and the end float of the worm shaft to reset.

However theoretically if I had a big enough valve block and pipes with the engine running at 3000 rpm the winch drum would be doing 175 RPM, or a 1st wrap rope speed of 52 m/min (175 ft/min). In reality the pressure drops in the system will prevent you from doing this..... But it will (by my calcs - it could yet be a very ££££ white elephant) pull 8000Lb at the no load speed of a 8274 with drive assist. However how thw H14 will stand up to taking ~ 4 x the power superwinch rate it for has yet to be seen.

Some one stated that worm gears are irreversible and hence a brake is not needed...... Well worm gears are odd in that the efficency of a worm gear set increases as the speed increases. I believe that this is to do this the lack of oil between the worm and wheel at slow speeds, also the tooth movement is a sliding action rather than a rolling action - the faster the worm goes the more oil it pulls in to lubricate the sliding action. Hence at start/no speed the worm set in an H14 is only ~40% efficent, but above a input speed of 2000 rpm it is ~85% efficent (calculated using BS 721 prt1). This give the curious effect of the worm set being irreversible when static, but not when run at reasonable speeds - hence why huskys over run whan you lower out under load.


Link to comment
Share on other sites

Cheers for the picture, its a bit bling mate.

One more comment for john: If you are using the H14, your benchmark will have to be the PTO speed. Bearing in mind that the inputshaft will have a speed of the crankspeed/3.5 (1st gear ratio). So if your hydraulic set up beats 1 rotation on the inputshaft for 3.5 rotations of the crank, it will be faster. If not, you might as well chuck that propshaft back in.


Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...

Important Information

We use cookies to ensure you get the best experience. By using our website you agree to our Cookie Policy