Mf 7499 dyna-vt problem

[H.M.]

Hi, first time venturing into the machinery section [emoji33] I'm hoping someone can help (without confusing me too much[emoji1])
We've got a mf 7499, it's done about 2000 hours and we've had quite a few problems, my dad wants me to ask on here if anyone else has had these problems, because all he's being told is that it's all normal [emoji53]
So, the problems:
When working, the gearbox squeals, especially when turning on the headlands. It also smells of red hot oil, even though the machine is saying the temp is fine.
It doesn't have enough power when working heavy land, it doesn't just keep going with steady revs, it really struggles.
And, when it gets to the headland it's like it's' wound itself up like a coiled spring and it suddenly releases a burst of power and shoots forward before stopping.
Think that's it, any help much appreciated [emoji106]

 

[Chae1]

@Farma Parma

 

[mtx.jag]

@Cowabunga

 

[fredf]

Are you changing into low range when working hard? e.g. ploughing or pulling a big cultivator. The squealing is off the power steering when you are turning when holding on to full lock let the steering wheel go back a few degrees and the squeals should stop.

Tom

 

[Cowabunga]

It sounds like an engine problem.
There are no clutches in the transmission to heat and burn the oil, although a knackered bearing might heat up enough, but it is almost unheard of at those hours.

Could the PTO clutch be slipping or the 4wd clutch? No squealing in mine so far at 5000 hours.
You haven't been doing heavy cultivation in high range for long periods have you? That doesn't do it any good.

If you do a search you will find an example of someone who had horrendous issues with one of these tractors. But I know that that unit had significant issues before he bought it that was not the tractor's fault but which impacted on its reliability from the day he bought it. Luckily it had an extended warranty which covered the bills. Even so he probably regrets ever buying it.

Don't let that put you off, because it is a pure Fendt transmission that is generally very reliable.

 

[H.M.]

Are you changing into low range when working hard? e.g. ploughing or pulling a big cultivator. The squealing is off the power steering when you are turning when holding on to full lock let the steering wheel go back a few degrees and the squeals should stop.

Tom

Yes it's in low, and it's not when it's turning that it squeals, it's when it changes direction eg from from forwards to reverse and also when it's pulling up hill. Sorry I didn't make it very clear at first, it's not me driving it's my dad

 

[Cowabunga]

Are any other problems its had related to these ones?

At 2000 hours it is hardly run in.

 

[H.M.]

It sounds like an engine problem.
There are no clutches in the transmission to heat and burn the oil, although a knackered bearing might heat up enough, but it is almost unheard of at those hours.

Could the PTO clutch be slipping or the 4wd clutch? No squealing in mine so far at 5000 hours.
You haven't been doing heavy cultivation in high range for long periods have you? That doesn't do it any good.

If you do a search you will find an example of someone who had horrendous issues with one of these tractors. But I know that that unit had significant issues before he bought it that was not the tractor's fault but which impacted on its reliability from the day he bought it. Luckily it had an extended warranty which covered the bills. Even so he probably regrets ever buying it.

Don't let that put you off, because it is a pure Fendt transmission that is generally very reliable.

Thanks, an example is it was baling on a steep hill and the tractor stopped, lost drive on pedal mode and started squealing so my dad selected stick mode and pushed the stick forwards to get it to drive up the hill before it went backwards into a quarry, the smell came from the backend round the trumpet housings and it smell there almost all the time it's working hard. The pto was still going when it lost drive and it's always in low for heavy cultivations and it was in low for baling that day

 

[davidroberts30]

Yes it's in low, and it's not when it's turning that it squeals, it's when it changes direction eg from from forwards to reverse and also when it's pulling up hill. Sorry I didn't make it very clear at first, it's not me driving it's my dad

Needs the gauges on the transmission
Sounds like a main relief valve is faulty

 

[H.M.]

Are any other problems its had related to these ones?

At 2000 hours it is hardly run in.

At 50 hours they'd (the factory) forgotten to put a C clip on the rear stub axel and it cracked the trumpet housing

 

[H.M.]

Needs the gauges on the transmission
Sounds like a main relief valve is faulty

They did that and said there was no problem, they pressure tested the transmission and said its within the parameters

 

[mtx.jag]

Are any other problems its had related to these ones?

At 2000 hours it is hardly run in.

Sounds like @saly123 over agen..

 

[Cowabunga]

Is the transmission oil black and smells burnt? That is usually caused in most transmissions by a clutch pack burning. There are no clutch packs in the transmission to the wheels on this transaxle so it does sound as if there's an issue with the main relief valve, as dr30 mentions above, but that shouldn't result in burnt oil or the smell of it unless temperature gets exceedingly high. Probably way in excess of 100C.

The only other thing I can think of is that it has been run short of transmission oil, hence the loss of pressure on the hill.

Its beginning to sound rather serious. Best if the dealer sorts it out. It may mean a full pressure test as specified by AGCO technical. If the dealer really cannot pinpoint the problem, they should not be shy about consulting the help available at MF technical support.

 

[Cowabunga]

Sounds like @saly123 over agen..

It does. But despite all his problems, that one had similar symptoms [i think] at very near 5000 hours, not 2000. Not that it makes a difference. I think a bearing had disintegrated in the planetary system and broken bits caused more damage in that one.

 

[H.M.]

Is the transmission oil black and smells burnt? That is usually caused in most transmissions by a clutch pack burning. There are no clutch packs in the transmission to the wheels on this transaxle so it does sound as if there's an issue with the main relief valve, as dr30 mentions above, but that shouldn't result in burnt oil or the smell of it unless temperature gets exceedingly high. Probably way in excess of 100C.

The only other thing I can think of is that it has been run short of transmission oil, hence the loss of pressure on the hill.

Its beginning to sound rather serious. Best if the dealer sorts it out. It may mean a full pressure test as specified by AGCO technical. If the dealer really cannot pinpoint the problem, they should not be shy about consulting the help available at MF technical support.

Yes to us the oils smells burnt but not to the dealer, it's never been short of oil and when he's tested the temp of the oil whilst working it was 88*c but dad worries about where the sensor is reading that from because it smell a lot hotter than it reads. Dealers want us to swap it and buy a bigger model because they can't sort it and say this is just how those models are, hence wanting to know if other people have found these issues

 

[mf7480]

88 degrees sounds hot to me, my 7480 will never show above 65 even on very heavy, slow draft work

 

[mf7480]

And I've never had any of the symptoms you have with your 7499, it sounds a bit like the vario might be goosed

 

[mf7480]

Is the backend hot to touch?

 

[H.M.]

Is the backend hot to touch?

Yes

 

[H.M.]

Sounds like @saly123 over agen..

Yes I've been searching on here today and saw he posts about his mf, his description of it getting hot and going limp sounds exactly like ours!