Milemarker Type S Posted November 15, 2007 Share Posted November 15, 2007 Fairly new to the forum so sorry if this topic has already been covered elsewhere- if so please point me in the right direction... I am currently trying to rig up twin ZF74 power steering pumps to up the line speed on my milemarker... My vehicle is a 1992 200Tdi 90 that I use in winch challenge events- I eventually want to upgrade to a proper hydraulic pump to be direct driven via a clutch in line with the crank- but this means changing pretty much all of the other components in the system- pipes, valve, reservoir etc etc... so this is a bit of a stop gap measure until the money tree again bears fruit!! I was originally running a LUX LF68 power steering pump (from a scrap 7 series BMW) running via a single belt from the crank pulley (changed to air con version to give extra V) which gave me 130 bar and a low gear line speed of only 3 foot 4/min at the drum (2.5 inch dia) and 6 foot 8/ min at the top layer (5 inch dia)- this gave a hell of a pull but hell of a slow... Nice for when the guy with the 8274 in front of you has just burnt out his motor trying to double line pull himself out of the 100 foot long door deep plop heap and you can slowly but surely plod through it on a single line pull, (whilst eating a corned beef and pickle roll if I remember correctly! ) but fairly plop for any other possible scenario!!! I have mounted the two ZF74 pumps next to each other in the air con slot with one 13mm V belt from the crank to the first pump, and a second short 13mm V belt from a second pulley on the first pump to the second pump- the tension of the crank to pump 1 belt is tensioned by moving the pump mounting sideways and the belt from pump 1 to 2 is tensioned by an idler pulley from a V8 air con pump. I have fed the high pressure feed from pump 2 through a one way valve and then joined both high pressure lines from the pumps via a T piece into the original milemarker hose to the solenoid valve- this allows me to slacken the idler and take off the short belt when I am not using the winch to stop the second pump spinning aimlessly. I soon discovered when trying to winch out that the small metal disc in the solenoid valve was a bit too 'restrictive'... the belt from crank to pump one started to 'Riverdance' and bits of rubber started flying off!!!- not pretty. Disc has now had a slightly bigger hole drilled and edges smoothed to ease the flow and the system now works in and out with no problems at no load. The low gear line speed is much improved with the twin pumps... 8 foot 6/min at the drum and 17 foot/min at the top layer- just over 100 foot/min in high gear... better The problems start when the winch is loaded up such that the pressure reaches about 80 bar which is probably only about the 2.5 to 3 ton mark? The belt from the crank to pump one starts to jump and skip with a nice display of rubber bits flying about!! Clearly the single 13mm V belt is not man enough for the job of running both pumps but I am a bit stumped as to where to go next- twin belts is the obvious option but I cannot see how to run twin belts from the crank without completely making a crank pulley with four V's- anyone done this and got any pictures of how to do so? Or indeed any other ideas?? Also has anyone managed to get a twin ZF74 system running with the original MM solenoid valve?- The max flow rate seems to be generally quoted as 3.5 UsGal/min but when I spoke to tech support at MM they said that it would take 7-8 UsGal/min?? Any ideas very welcome- and the cheaper the better as I have already invested about £500 in this 'little' upgrade- as usual had I known that all the little costs would have spiralled this much then I would have been better to just go straight down the direct crank driven pump route... Again sorry if this has already been discussed. Shrek Quote Link to comment Share on other sites More sharing options...
Bull Bar Cowboy Posted November 16, 2007 Share Posted November 16, 2007 Shrek, I run a PTO pump …………….. about 60L/min ………. The MM does about 50ft/min in low and 300ft/min in high with a stall of about 6T …….. the PRV is set at 2500psi…………… but to wont get much change out of ££££ If you look in the technical archive you will find my set up under a thread called “Fast Hydraulic Winch build” ………….. there you will find all the MM calculations with regards to flow / speed & pressure / load The Std MM solenoid will not do much more than 3.5US Galls ………. then it starts to protest…………. BTW …………. I passed you about 2 weeks ago ……….. you were coming out of Tesco’s and I was heading into town from the kingsteignton direction…………mine is the caged V8 blue truck cab………………. Ian Quote Link to comment Share on other sites More sharing options...
steve b Posted November 16, 2007 Share Posted November 16, 2007 Why not run a larger hydro pump using twin vee belts and an air-con clutch as a intermediate mod , eventually using the same pump as a direct drive later , as BBC says the biggest restriction is the std MM valveblock only flowing 3.5 usgpm. 1/2" pipes and a valve block to suit , which you can use on your final setup . From what I've read in various posts you should be able to run this set up at about 1500- 1800 psi off belts but will get line speeds more like BBC quotes. The Crank drive would allow max psi (2500) at a later date. Cheers Steveb Quote Link to comment Share on other sites More sharing options...
Milemarker Type S Posted November 16, 2007 Author Share Posted November 16, 2007 Hi Ian, Thank you for the reply- did I wave back at you?- if not then I was as usual asleep sorry- will try harder... I take it you are local then? I have read that tech archive- excellent info and explainations- and most worryingly I understood the calculations!! I am looking to avoid the PTO pump route as I need to be able to winch and drive- not to assist the winch pull wise (nearly 5 tons is more than enough!) but for positioning of the vehicle. As I said this is somewhat of a stop gap measure but is turning out to be an expensive one... From my calculations- using only the speed at which the drum is rotating- I only seem to be getting flowrates as follow: LF68 6.26L/Min, One ZF74 7.65 L/Min and Twin ZF74 15L/Min. I was quoted 13L/Min for the ZF74 and therefore expected about 26L/Min from two- this equates to just under 7 UsGal/Min. Running as it is the Solenoid valve seems happy when in the centre position, and the fluid only really heats up when diverted through the winch- I am assuming that the holes in the spool inside the valve are smaller when fluid is diverted than when in 'open centre' position with high pressure just being returned to the tank? Shrek Quote Link to comment Share on other sites More sharing options...
Milemarker Type S Posted November 16, 2007 Author Share Posted November 16, 2007 Hi Steve b Sorry must have been replying to BBC at the same time as you were replying! I looked in to getting a proper hydraulic pump and 12v belt driven clutch- I got quoted £430 for a 15cc/rev pump with the clutch- the clutch was a twin v belt type- I was hoping to just stick to one belt at the moment because it appears to be a b1tch of a job rigging the crank pulley to allow for twin belts- that is the real stumbling block for me at the moment. I would be happyish with the speed of the twin system for the time being if I could find a simple way to drive it up to full load with the twin pumps. Has anyone got a twin V belt running a pump from the crank and if so how did you get around the crank pulley problem?? Piccys would be V helpful- Although I have a small lathe I am not up to completely manufacturing a quad pulley!! When I initially looked into it I was of the mistaken belief that one belt would run two ZF74 pumps with no problems and therefore thought it would be the easiest route for the time being, also that the flowrate would be about the max that the standard valve could handle (although it appears that MM have got this wrong themselves!), and that it would have been cheaper than it has been- how wrong can you be?- Must admit to a slight 'Teddy out of cot' moment when I found things not working as they should It looks like I may just have to sell off the new bits and revert to the original pump for the time being and wait until I can go the whole hog with a system similar to Ians but with the pump in line with the crank. Thanks again for the advice- very gratefully recieved. Shrek Quote Link to comment Share on other sites More sharing options...
Milemarker Type S Posted November 16, 2007 Author Share Posted November 16, 2007 And to top it all the cable retaining bolt on my drum has now sheared off... new one on order- now just need to get the broken bit out... As usual there is a tiny bit left protruding just enough to tease me into thinking that I will be able to grip it with something... Fat chance! Shrek Quote Link to comment Share on other sites More sharing options...
Daan Posted November 16, 2007 Share Posted November 16, 2007 Since you planning on running 2 pumps, why dont you run one pump from the belt and one pump of a pto? That would be my solution on first attempt since that will give you the best of both worlds; I am sure some non return valves would be neccesarry but that wouldnt be the end of the world. daan Quote Link to comment Share on other sites More sharing options...
BogMonster Posted November 16, 2007 Share Posted November 16, 2007 PM me your email address and I will send you a load of stuff which a bloke sent me a year or two back, he had twin ZF74s up and running on a Milemarker and sent me pics etc. I always intended to write it up on the forum but never got around to it I am pretty sure his was a 300Tdi but it might give you some ideas. Quote Link to comment Share on other sites More sharing options...
SiWhite Posted November 16, 2007 Share Posted November 16, 2007 I think you may be on a hiding to nothing trying to run the pumps with a single belt. I used to burn out single 13mm belts running a 90a alternator with my 8274 - they're really not great at transmitting power - they start to slip, creating heat, creating burnt out belts. Can you tell I'm not a fan of them? I've got a 47cc/rev pump which I'm going to use with my MM. I wanted to drive it using a propshaft off the crank nose but the pump is designed to rotate the wrong way for that so I'm going with a synchronous belt (like a timing belt - I just like using long words!) driven off the crank nose. Progress is limited as ever by lack of time and money, but the crank pulley is done... photos to follow when I can get them hosted. This MIGHT NOT WORK, and it's not been proven in the real world by anyone that I can find, but it's been fun making it. The main concerns are that it won't be very stones-and-branches tolerant, but I might make a simple cover for the belt and sprockets if it's a problem. Parts were cheap - two Transit cam pulleys and two belts were a fiver from my local breakers. I need to get a bigger sprocket from somewhere engineering-ey for the pump as the Transit ones are too small to fit over the clutch. You could use something similar - two pumps both with a sprocket like above and a small idler at the bottom in between them. The belt would come from the crank and around the sprocket of the outer-most pump, round most of it before hitting the idler, then back up and round the second sprocket before returning to the crank sprocket. Quote Link to comment Share on other sites More sharing options...
SiWhite Posted November 16, 2007 Share Posted November 16, 2007 Quote Link to comment Share on other sites More sharing options...
Milemarker Type S Posted November 16, 2007 Author Share Posted November 16, 2007 Thanks for the good info guys- much appreciated. I had considered running a toothed belt which would obviously negate any belt slip but had two concerns- firstly they are very intolerant of misalignment- not sure of exact figure but I know they need to be pretty much bang on to stop them eating the belt and secondly the 'debris' issue- stones, twigs and mud getting all caught up... would be excellent to see how you get on as if you can sort the alignment issue some sort of guard may well be the way forward debris wise- thanks for the piccys- like the green paint!! Si - Are you going to run the 47cc/rev pump with a standard MM motor?- is that not going to give it too high a flow rate?- I was looking at more the 25cc/rev level which would give you 25l/min at 1000rpm and 62.6 l/min at 2500rpm- I think in Ians thread it gives 60l/min as a max flow for the standard MM motor- you would be giving it 117.5 l/min at 2500rpm with that pump??!! If my maths is right that would give you 575 rpm of the winch drum in high gear- 750 ft/min line speed at the top layer of the drum? - i would not want my fingers near that!!- Hopefully Ian will correct me if I am wrong on the figures. If yo are using a larger capacity motor then these figures all go out the window in any case. Bogmonster - PM sent thanks. The good new is that the broken off bolt came out with no problems- small slit across the surface with a mini grinding disc and undid with a screwdriver - still in shock as I had visions of having to drill the begger out! Quote Link to comment Share on other sites More sharing options...
Bull Bar Cowboy Posted November 17, 2007 Share Posted November 17, 2007 It really depends on the max rpm of the pump ................ a lot are only 1500rpm max ............. therefore Si will be fine............. Mine is 2500 rpm ..................... and sure enough it cavitates at around that speed ............. a rather unpleasant noise ! Ian Quote Link to comment Share on other sites More sharing options...
Milemarker Type S Posted November 18, 2007 Author Share Posted November 18, 2007 Mmmm cavitation... the lovely sound of metal literally being plucked from the metal surface Bogmonster- thank you for the info you sent me. Lots of good stuff amongst it which when I get a chance I will sort out for the forum if that is ok? The info about the valve block was especially useful- if the spec sheet I have is for the right valve (can anyone remember if there are any numbers on the standard MM valve block?- or indeed know what model number it is??!) then it suggests that the sensible flow limit is 26L/min (about 7 USGal/min) at 210 bar- the spec sheet at first inspection does not make reference to the little flat valve- but I appear to have sloved that issue anyway. The info also relates to the install of twin ZF74 pumps on a 300tdi which has multi v belts as standard. It appears that the two pumps can be succesfully run via single multi v belt from the crank. The lay out is pretty must as described by SiWhite- two pumps next to each other belt from crank to pulley of pump one, pretty much all the way round the pulley, down to an idler and then all the way round the pulley on the second pump and back to the crank- this appears to be a good design as the surface area of the belt on each of the pump pulleys is maximised. There is mention of the belt slipping slightly but only when at the limit in high gear. The long and short is that I am somewhat more positive about this set up possibly working . Now I just need to work out how to graft a mutli V pulley into the middle of my existing triple V belt crank pulley in place on the central V... Si were you able to weld the toothed pulley to an existing pulley? Also I take it if the pumps you guys are using are limited max rev wise that you just have to hold back on the loud pedal? What happens if you exceed the max rev limit- does it just start to cavitate as BBC suggests?- which would obviously not kill he pump immediately or does something more dramatic happen? Again- thank you all for help and advice- very much appreciated! Shrek Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted November 18, 2007 Share Posted November 18, 2007 I dunno much but I too think you're potentially wasting time running twin pumps and V belts, they're not great at transmitting decent power as has been proved with big alternators. I'd look at a single big pump (a ZF74 is still only a PAS pump) crank driven, chain driven, or PTO driven (and live with limited assist). Quote Link to comment Share on other sites More sharing options...
Manxey Posted November 18, 2007 Share Posted November 18, 2007 If it makes any difference i beleive alfred murray has brought out a new PTO pump, that runsfast enough so that you can winch and drive! Quote Link to comment Share on other sites More sharing options...
Milemarker Type S Posted November 18, 2007 Author Share Posted November 18, 2007 potentially wasting time. Have you been speaking to my opinion missus?- she seems to think that is the case for me 99% of the time! As I said this was only intended as a short term stop gap measure that I really thought would be quick and easy to rig up... just to improve my line speed to a slightly more acceptable snails pace! I totally agree that the proper solution is a hydraulic pump positively driven from the crank and when funds allow will be properly sorted! I have heard of the bigger capacity PTO pump available- anyone got one? Shrek Quote Link to comment Share on other sites More sharing options...
Milemarker Type S Posted November 18, 2007 Author Share Posted November 18, 2007 It also appears from another thread (MM install photos) that 'Old spot' has exactly the direct crank driven clutch and pump set up that I aspire to... Looks damn fine- now very jealous Makes you wonder why someone like Alfred Murray has not gone down this route as by his own admission the larger pumps being chain/belt driven from the crank are starting to raise some crank bearing 'issues'?? Shrek Quote Link to comment Share on other sites More sharing options...
Old Spot Posted November 18, 2007 Share Posted November 18, 2007 Here is my solution to smokin belts- f**k um off. Quote Link to comment Share on other sites More sharing options...
Milemarker Type S Posted November 18, 2007 Author Share Posted November 18, 2007 Here is my solution to smokin belts- f**k um off. Thats the begger!! Any chance of you divulging some more info???- Details about pump/clutch/mounting/performance/pros/cons etc?... Pretty pretty please... Also did you have any issues with the alignment of the unit with the crank? Shrek Quote Link to comment Share on other sites More sharing options...
SiWhite Posted November 18, 2007 Share Posted November 18, 2007 Si were you able to weld the toothed pulley to an existing pulley? The pic is of a standard single belt pulley with the toothed sprocket welded on. I welded a steel plate onto the front of the standard pulley, welded the sprocket onto that plate and then another onto the other side of the sprocket to act as flanges. Runout was a pain to sort out but we got there in the end. Quote Link to comment Share on other sites More sharing options...
Milemarker Type S Posted November 19, 2007 Author Share Posted November 19, 2007 I take it you are up and running now then? When you say a bit of a pain... how painful?? Quote Link to comment Share on other sites More sharing options...
Bull Bar Cowboy Posted November 19, 2007 Share Posted November 19, 2007 OK, OK …………………… its time to look at some numbers ………….and you will find that to get the right combo for true drive assist is very, very difficult………….. Winch /Drive assist with an electric winch works because the winch speeds up as the load is reduced …………… couple that with also using an underdrive and you get near to perfection for that technique, where the wheel speed closely matches the line speed………………..however………….. Hydro winch’s always turn at the same speed regardless of load …………….. to winch drive correctly the rope speed needs to be very close to the wheel speed ................... So ………….. 1 mph = 88ft/min ((1760 x 3) /60) Assuming most trucks will be (or a derivative of) LT77 / LT230 /std Diffs 3:54 / and I will assume a wheel diameter of 33inch (bigger makes it worse !) ……………then the lowest wheel speed (1st gear) will be 2.32mph @1000rpm………….(2.976 x 33)/(3.6 x 3.321 x 3.54) So to match your lowest usable wheel speed (even diesels do not have a lot of useful torque below 800 – 1000 rpm) …………. Then your winch needs to be recovering line at 204ft/min ……………..(88 x 2.32) So, even for an engine driven pump the situation is dire ………………for a PTO pump the numbers are worse ……….. for the pump to turn at 1000rpm then the wheel speed will be 8.35mph …………… Now the crunch ………….. if you have been winch trained to commercial standards then you will know that drive assist is a very large NO ………………….. however, it can be useful in certain instances……….. like assisting the wheel to ‘climb’ over an obstacle ……. but even then that is just a very short burst of ‘drive assist’ My experience suggests that with a fast hydro winch you will not need drive assist very often at all …………. just let the winch do the work …………….but I can assure you that Drive assist with a PTO driven pump is possible (with care) for those short bursts that may be required. I guess we can summarize this with, 1) The Zf74 pump is not flow dependant upon engine revs , but the flow is no where even near enough to turn the winch at anywhere near the required speed ………....... my experience suggests that the quoted flow on these pumps is never acheived ........... more like 75% 2) A crank driven pump will be rpm dependent with regard to flow and also have a max rpm that cannot (should not) be exceeded……………… that combo has its limitations…. 3) A PTO driven pump is also pump rpm dependant with regard to flow and also has a max rpm that cannot (should not) be exceeded ……………… as the pump is driven from the gearbox, then the wheel speed will always generally be higher then the line speed, however, this system allows for flexibility in terms of ultimate winch control. My only mod in the future will be to use a higher capacity pump in order to get a higher flow rate at lower RPM ………………….. 60 – 100 L/min at 1000 – 1200 would be perfect ………. Another consideration that has not been mentioned is reservoir size ………..in our case this should be roughly 50% of the pump max output…………… most commercial systems use 250% ………………………In the early days, I boiled the fluid in the std ZF74 reservoir, when I was running the ZF74pump …………… Boring lesson with lots of numbers is over …………….. Ian Quote Link to comment Share on other sites More sharing options...
BogMonster Posted November 19, 2007 Share Posted November 19, 2007 Here is my solution to smokin belts- f**k um off. I want one Quote Link to comment Share on other sites More sharing options...
Bull Bar Cowboy Posted November 19, 2007 Share Posted November 19, 2007 A little bit more info to digest .................... The MM usually uses (unless its very early or a Type R) a 'Whites Hydraulics' motor .................the cc/rev of the motor depends upon whether it was used with a LR steering pump or the ZF74 pump...............IIRC most for use with the ZF74 pump were 200 series motors ..................... Attached is all the Whites RS series motor info ............ I have split the file to stay within the 2MB upload limit. This info will give you the shaft speed and torque for any given flow / pressure ............. from this you can then work out the drum speed and stall load of the winch (IIRC.............. G/box is 6:1 and the drum dia is 2.5inches on the first wrap, ignoring the dia of the rope) Winchmotor_1.pdf Ian Quote Link to comment Share on other sites More sharing options...
Bull Bar Cowboy Posted November 19, 2007 Share Posted November 19, 2007 Here is the second part of the whites motor info ............... Winchmotor_2.pdf Ian Quote Link to comment Share on other sites More sharing options...
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