Hi all, I'm in need of some help please. I own a 1996 Sumitomo SH145U, ugly but tough little digger, 14.5 Ton - Zero swing. I was reading wgwestervelt's Track Speed Issues - Kobelco thread and thought I'd have a go at the info given there. In particular this: So the problems begin in the fact that I have four pipes (see pic)... and continues with the issue that oil comes out of both the two smaller ones at idle once the safety lever is engaged. Could one of the smaller lines be a pilot/control type line for the two speed diff? Placard info pic if it makes sense to anybody. The KNA prefix number is Gen-Sumitomo numbering from past experience. First pic posting attempt, so sorry up front if I got it wrong...
Hey mate, sorry for the short and sweet reply but I'm in a rush! I'm assuming you have the same problem as wgwestervelt. The two larger hoses are the supply and return lines for the travel motor (obviously depending on which way you travel will determine which way about they are) The smaller one is the pilot supply hose to the travel brake. The smaller of the larger 3 hoses is the case drain from the motor.
No worries, thanks for taking the time. My concern lies in that the whole digger is getting slow (or seems to be getting slow) and I'm trying to pick the worst things out to fix. OK, the case drain line is the top hose in that photo then. I disconnect that, do I block the hose somehow, while I look for oil leaking out of the fitting at the travel motor while it's engaged? I'm guessing it will be open circuit to the reservoir and just leak out other wise - also assuming that there would be no pressure there?
Your right about this, no pressure just abit of run back, blank it if you have a plug! what is your machine doing exactly, how slow is it getting?
The case drain line is soft like a low pressure line, so I felt safe enough to clamp it as I don't have a plug and a taped up plastic bag wouldn't hold it - LoL. Machine is slower to track than it used to be i.e. I find myself dropping back down to 'turtle' speed when even going up a slight rise, when it has done the same or similar tracking with 'rabbit' setting in the past. I notice it most when I am climbing up step hills though; in low or 'turtle' setting and using the bucket to pull up the hill, there is little to no tracking effort. Is there a pressure different between the two track motor settings or is it just a flow setting? CPS, I just did your check. There is a initial pulse of fluid out of both the travel motors drain nipple/connector on first application of the travel lever, it slows immediately to a minor flow, one might call it a trickle I guess. Drained the final drives gear oil, silverly not black and level was right before draining, with no bits of metal attached to the drain bung - that's OK isn't it?
It is normal for oil to be coming out of the case drain hose and pilot supply hose to the travel brake under these circumstances (disconnected and machine running). The oil from the case drain hose will be coming directly from the return filters either inside the hydraulic tank or remotely mounted (leak oil case drain filter on larger machines), depending on the position of this hose in relation to the tank and/or hydraulic oil level will determine whether the oil is coming from the tank itself either from head pressure or gravity fed. It could simply be that it is just the volume of oil in the hose itself and will stop once drained. The oil from the pilot supply hose to the travel brake should only be the residual oil from the hose, as with smaller excavators the travel brake is always engaged (spring applied, hydraulic released) while not travelling. Anyhow, all of this is irrelevant as you want to see the volume of leak oil from the motor, not the hose Your right, it will be low pressure. Off the top of my head, I think it's somewhere around 3 bar and 3.5 bar is considered to be excessive as you would get the fault message "leak oil case drain filter restricted" (on the machines I work on) but just to give you a rough idea. That’s fine, that’s what you want. The case drain is there to relieve the pressure caused by leak oil between the piston and barrel otherwise pressurising the motor case and blowing out the shaft seals. The test that CPS mentioned is just to determine whether or not your travel motor piston to barrel clearance is not excessive due to wear, which would cause a drop in oil pressure (no travel power) and flow (slow speed). No metal on the magnetic plug is good; I don’t like the sound of the silver colour oil though, got a photo? Have you tried what I posted in wgwestervelt's thread? You'l need gauges though
I went back over to take a pic but it's mixed in with the other left over oil in the drain tins and now just looks black. It just looks like silver oil, same as what you see in an old Holden diff Take pity on the old petrol mechanic, I can't explain it any better. If it's dropping a bearing it's going slowly, the silver has been there for the last 1,500 hrs. No not yet. Edit: found someone to supply test gear, should have it tomorrow.
Try this . I had a quick look, couldnt see a kit like you asked for, Pirtek sell's the stauff kits which is what I have and just built on with freebies from work and my Dad's over time (I know you dont have access to a Pirtek) but their basic (3 gauges of your choice, 3 test hoses of your choice, numerous test fittings and adaptors, a stauff rag to keep them clean, a box with foam cut-outs to keep them all safe and secure and a pirtek fitting identification kit) and very expensive.
I was mistaken, the smaller hose is actually the pilot supply line to the the motor two-speed governor.
No worries Chris, I managed to get the Stauff gear you listed in the other thread late this arvo. $185 inc tax So it's now just going to be a matter of finding some pressure specs to line up against. Ever done final drive bearings r&r ? Big job? I guess I should do it, before it gets unrepairable.
Does that mean it does run through some internal reduction gearing in the travel motor/final drive then?
G'day Digger I reckon you should be checking out the swivel joint before you do anything else cos if the seals are worn in there it will be redirecting oil all over the place even pressurizing the casedrain.To much pressure in the casedrain can lead to hydraulic motor failure and that hurts. Hope this helps and you get it up and running soon :drinkup Tones
the travel speed is not change by gears its changed by oil pushing the angle of piston rotary group witch increase oil flow in the travell motor. this is no inportance to your problem reading your problem s seems to me u are saying every thing is slow my recomed time all function with stop watch record time on paper u need time cycle specs from work shop manual this is step one remeber slowly slowly catches the monky