Merlo hydrostatic slipping
- Thread starter Logbrog
- Start date
- Location
- East Sussex
Sounds like ours. Is it a deutz engine? We thought it was the hydro. It turned out to be the diaphragm in the fuel pump had a hole in it So wouldn't give boost pressure. Would rev fine but just didn't quite have the guts it should have.
Failing that it could one of the potentiometers, I think there is 3, which your merlo man can check with a lap top. This is probably more likely as apparently these do fail after a time.
Failing that it could one of the potentiometers, I think there is 3, which your merlo man can check with a lap top. This is probably more likely as apparently these do fail after a time.
x121x
Member
- Location
- Somewhere in the dark
Very unusual for a hydro to slip. The way the system works the hydro works the same in both first and second gear, it's more likely to be an issue inside the transmission. Drain the oil and see if you have any filings or metal in there.....look directly under the machine at the gearbox and you will see the drain plug.....27mm bung if I remember correctly
- Location
- south norfolk
@ACEngineering
Nick...
Nick...
ACEngineering
Member
- Location
- Oxon
It would give impression of slipping if a relief valve failed though.
x121x
Member
- Location
- Somewhere in the dark
Yes but it wouldn't drive in first gear either, if the hydro was slipping all drive would appear lost rather than working ok in one gear.
ACEngineering
Member
- Location
- Oxon
your joking right cant stand the things.Not done much with hydro transmissions. Did a manitou course on them many years ago but never really pulled any apart.
ACEngineering
Member
- Location
- Oxon
Do they still have a mechanical 2 speed gearbox?
The schaffers had 2 speed motors but that wasn't so good when it came to road work as lack of torque.
x121x
Member
- Location
- Somewhere in the dark
Yeah still a pretty basic two speed transmission. It's the only thing that varies the speed, they hydro does the same work on both, so it's probabaly likely an issue in the transmission. I could be wrong though.....
- Location
- Essex
If the design is unchanged there is a switch on the control panel which gives 100% drive or a variable percentage of that figure. Check the switch hasn't been knocked across.
x121x
Member
- Location
- Somewhere in the dark
That would affect both gears, I think the key here is that fact there is some strange noises in gear one
Right-arm fast
Member
If it's in a lower gear it would be less inclined to blow over a pressure relief valve as it would take less oil pressure to move be the machine?
x121x
Member
- Location
- Somewhere in the dark
Possibly but the way the system works it's highly unlikely, in all my experience I have never seen any pressure issue or valve issue that hasn't affected both speeds, the fact it drives but is noisey in first gear would suggest the transmission. Easy way to tell is to apply the handbrake and drive against it to see if the hydro creates max pressure, this can be checked with the gauge in the cab
TripleSix
Member
- Location
- Helmsley, North Yorkshire
Is the foot brake stuck on?
They're sods for seizing up on the axle.
They're sods for seizing up on the axle.
Last edited:
- Location
- East Sussex
From what I was led to believe just a few weeks ago they have very few hydro problems. Most issues are caused by the potentiometers failing or possibly coming loose (which happened to ours when we first had it) rather than hydro issues.
We reconditioned our gear box a month ago. It made a nasty sound when at speed but it didn't affect the drive at all. Very easy and cheap to fix, worst part was fitting it back in which was a bit of b*tch. As said above check the oil for filings and you will soon know if there is a problem.
We reconditioned our gear box a month ago. It made a nasty sound when at speed but it didn't affect the drive at all. Very easy and cheap to fix, worst part was fitting it back in which was a bit of b*tch. As said above check the oil for filings and you will soon know if there is a problem.
Rust
Member
- Location
- Hertfordshire
Well it can't be a slip in the gearbox.
Either it will or it won't cogs don't "slip"
Either it will or it won't cogs don't "slip"
x121x
Member
- Location
- Somewhere in the dark
Can't be too big an issue after two days of suggestions and no update on the "issue"