Lifton LS850 wont drive uphill

[CaptLimey]

"What is it you feel is the main problem, from here ? General lack of power ?"

Hi Muz

Lack of power? - if anything yes, but not all the time, only under load on an incline.

I used the Lifton all day yesterday moving a pile of earth from the front to the back of our property, with a skip full of damp earth/stones on each of about twenty journeys. The machine pulled well on the flat and slight incline, even up to full speed of around 35kph. But when it hit the 1 in 7 incline it slowed to a crawl of less then 3kph. There were times when I thought it was going to stop completely, but it didn't and sped up again when on level ground. The high lift and tip functions worked superbly but they are on a separate pump.

Maybe I'm expecting too much of a small machine but I just have the feeling that it should be doing a little better than a laboured crawl on the steep incline?

My hydraulic 'expert' chappie is coming over next week and we'll see what he has to say. Maybe he can advise on 'tweaking' a few adjustments to fine tune it - watch this space!

Rgds CL

[jackpreacher]

Hi Cap'tn, after reading through the whole thread again I have these questions:

1. Did the 'engine bogging down' under load ever get sorted out?...or did the question of engine power [or lack of] ever get fully investigated?

2. Also, when Stevey and you [I presume] did the rebuild did you touch the engine?



BTW, what is the rated power of the motor?

[CaptLimey]

Hi Cap'tn, after reading through the whole thread again I have these questions:

1. Did the 'engine bogging down' under load ever get sorted out?...or did the question of engine power [or lack of] ever get fully investigated?

2. Also, when Stevey and you [I presume] did the rebuild did you touch the engine?



BTW, what is the rated power of the motor?

Hi Jack

Re your questions, I'm not sure I can answer them as Stevey made those posts and did the rebuild which, I don't think, as far as the engine is concerned, involved anything other than the usual maintenance issues of filters and oil change etc.

I can say that the engine keeps going well but is clearly working hard on the steep incline.

Stevey hasn't had the opportunity to compare for himself the current performance with that immediately after rebuild and probably won't until into May or June.

Re rated power output - don't know without referring to the manual and that's a glass of wine (or two) too late! Will post again when I find it.

Rgds CL

[Stevey]

Stevey here, cheers for your replies to Cap'n ( my father in law) Short answer to the last post.

When we rebuilt the lifton, the engine wasn't touched, apart from basic service items. So in neutral it would rev freely. The bogging down I described was the engine labouring to the point of almost stalling to drive the thing forward. Exactly as you would get if you tried to drive a car with a handbrake fully applied. Nothing else mechanical was touched.

Enjoyed seeing all the posts on this one. I look forward to it working well again chez moi in the Pyrenees.

Stevey

[CaptLimey]

Hi Jack

You'll see that Stevey as responded to your earlier questions.

Re the rated power output, I found this in the 1001 model manual "Engine output 12.1 kW at 2200 rpm", later engines were 17kW.

I also found this "Hill climbing ability 45 %" which I recon is a rise of about one in two point five. Our machine has a problem when loaded getting up a one in seven rise! Maybe that climb rating is for the later 1001 model with the more powerful engine OR we do have and engine power output deficiency?

Rgds CL

[jackpreacher]

?..... The bogging down I described was the engine labouring to the point of almost stalling to drive the thing forward. Exactly as you would get if you tried to drive a car with a handbrake fully applied...........

I have 2 theories:

1. The engine is not producing its rated power so it struggles to produce 360 bar when it needs to - ie. hill climb with load.
2. The reliefs are set too high so that the engine strains to maintain revs under full load/hill climb - as the revs drop off so does the flow rate(not pressure) to the travel motors, hence speed is reduced.

There was some playing around with settings wasn't there?
Anyway, when under full load, what is the exhaust like?

[jackpreacher]

.......mind you , lugging nearly a ton up a pretty steep incline with 15 HP is no mean feat!
45% incline capable? I wonder if that is part loaded, if at all.......

[CaptLimey]

Update

Hi All

Jack re settings yes there was some 'adjustment' of settings but we've tried just about every combination/variation with no marked difference,
re exhaust when under load - dark - but no more than any diesel when working hard under load.

Our friendlly expert John, came to see and advise and he'd read the historic posts on this forum before he came. He said that as we'd tested the pump and found 310 bar he didn't think the pump was the problem rather that the issue was probably one of flow or drive motor(s). I told him that recent test drives has shown that the front right wheel was still prone to lock up, a symptom that Stevey experienced way back. He emphasised that the finding of sand in the right front drive motor (Stevey's earlier post) was a strong indicator that there could be some seal damage causing the lock-up by high and low pressure equalising in the motor and stalling it. He suggested that the problem could lay in that drive motor and we should should dismantle it so he could look at the innards.

I removed it and dismantled yesterday it but couldn't see anything obvious with my inexperienced eye and there was no suggestion of residual sand in the motor. I researched a new seal kit for the motor and was shocked to be told that they cost 340 pounds for a set of what appear to be sophisiticated 'O' rings!!!

John came yesterday pm and was surpirised to find only a minor scratch one one of the components, probably caused by sand, when he'd expected to find severe damage causing the lock-up. He said that the seals were so expensive because they were special Teflon material and extremely hard wearing. He examined the seals which didn't appear to be damaged but said it is very hard to determine anything other than obvious break damage on Teflon seals. In his opinion the motor didn't appear to be damaged to the extent of preventing normal operation.

He suggested we re-assemble the motor and install it on the opposite, left, side of the front axle and move the left side motor to the right. If, when installed and running, we still get a lock-up on the same motor it will prove the motor is at fault and justify buying a new set of seals.

If the front right wheel is still the one that continues to lock, after having swapped the motors, it will suggest that the problem is one of flow rather than the drive motor and we can trace back to try to identify the cause.

So watch this space!

Rgds CL

[CaptLimey]

Update

Today I re-assembled the dumper right drive motor and installed it on the left side after moving the left motor to the right side. I had to swap the hose adaptors to get the flow direction correct but all went well on start up - all wheel rotating in the same direction!

However when I took the machine on the same test run that illustrated the problem with the right wheel locking on an incline, it was repeated exactly as before. The front right wheel after about 20 meters on a loose/slippery inclined surface eventually locking and the engine labouring almost to stalling.
Fortunately we have eliminated the suspicion that the motor was at fault without shelling out 350 quid for a new set of seals!

We now have to research the next step working backwards and concentrating on the distribution/flow from the drive motor. Any suggestions?

Cheers CL

[Muz]

I take it all the hoses that were re assembled were original ? .. Ive had experience of a ferrule crushing the insert on a made up hose before now due to incorrect compression? ... thereby restricting flow ?

[jackpreacher]

It is probably a contaminated hose to that motor. It could also be an internal laceration or pressure related blockage - the hose behaves normally under moderate pressure but under full load the laceration shifts against the flow hence stopping flow to the motor. Change the hose.

[Muz]

It is probably a contaminated hose to that motor. It could also be an internal laceration or pressure related blockage - the hose behaves normally under moderate pressure but under full load the laceration shifts against the flow hence stopping flow to the motor. Change the hose.

I dunno Jack .. theres a few devices in there, to regulate the flow and any one of them could be at fault. But we dont know what they are ? .. this is all new ground

But at least weve eliminated the pump and the drive motor .. so we have good progress

Bear in mind this is a very high pressure system, so its got to be something mechanical and substantial causing the flow restriction.

[jackpreacher]

I dunno Jack .. theres a few devices in there, to regulate the flow and any one of them could be at fault. But we dont know what they are ? .. this is all new ground

But at least weve eliminated the pump and the drive motor .. so we have good progress

Bear in mind this is a very high pressure system, so its got to be something mechanical and substantial causing the flow restriction.

Yeah Muz, I was a bit rash - sorry Cap'tn - methodical elimination always beats 'bash it and see'

[CaptLimey]

Thanks for the comments guys.
Re the hoses I believe Stevey re-used the originals on the re-build.
I've sent information of the test and the result to our resident expert John together with the PDF of the manual. He's of the same opinion, that there is clearly a flow problem and he's going to refer to the manual flow circuit to see if there's a component that may be faulty and needs testing/adjusting. Failing that, it may be that examining/replacing the hoses is the most likely and least expensive next step.
Rgds CL

[CaptLimey]

Two or four wheel reverse?

In trying to determine the flow route of the hydraulic fluid and identify where the problem with our mini dumper might lie, I've hit a confusing snag.
The Neuson 101 manual that we're using suggests that the machine does not have a reverse High Pressure supply to the front wheel motors, only to the rear wheel motors. Can anyone confirm whether or not the small Lifton/Neuson dumpers have four wheel drive in reverse?

Also the parts manual shows two hose lines each linking the front and rear wheel motors on each side and identifies each of them as a 'serial line'. These hoses are each connected to a 'T' which appears to flow into two non-return valves which are in turn joined to a hose that is connected to the bottom of the hydraulic pump. I suspect they are the low pressure fluid return lines, can anyone please confirm that or alternatively tell me what their functon is?

Rgds CL