MF30 Instant reverse tractor Sudden failed to move

[jkk04]

A couple weeks ago, my beloved 1970 MF30 industrial tractor suddenly failed to move forward or backward while scraping on the ground.
The tractor has Perkin AD204 4 cylinders diesel engine.

The tractor has no indication of any noises nor wrong movement before it happens.

Only I suspect there was no fluid circulation in the transmission internally causing no pump and no supply of the fluid to the torque converter.

I replaced the transmission oil pump because of the seal failure and fluid and sump filter 7 years ago.

Ever since the tractor works without any problem.

Again, I removed the sump pan and cleaned some sludge and filter then added new fluid.

I thought the sludge was to block the fluid circulation through the sucking pipe to the oil pump.

But it did not help.

So, I removed the 1/8" pipe plug at the top of the transmission then connected a PSI gauge for PSI testing according to the service manual.

The pressure gauge shows only 40 PSI.

It should be between 150 to 160 PSI.

Is the pump failing?

I replaced the OEM oil pump about 7 years ago and it has served me for the last 35 years that I couldn't give up this lovely tractor.

Any suggestion from savvy members in here will be much appreciated

Jkk

 

[loggin]

A couple weeks ago, my beloved 1970 MF30 industrial tractor suddenly failed to move forward or backward while scraping on the ground.
The tractor has Perkin AD204 4 cylinders diesel engine.

The tractor has no indication of any noises nor wrong movement before it happens.

Only I suspect there was no fluid circulation in the transmission internally causing no pump and no supply of the fluid to the torque converter.

I replaced the transmission oil pump because of the seal failure and fluid and sump filter 7 years ago.

Ever since the tractor works without any problem.

Again, I removed the sump pan and cleaned some sludge and filter then added new fluid.

I thought the sludge was to block the fluid circulation through the sucking pipe to the oil pump.

But it did not help.

So, I removed the 1/8" pipe plug at the top of the transmission then connected a PSI gauge for PSI testing according to the service manual.

The pressure gauge shows only 40 PSI.

It should be between 150 to 160 PSI.

Is the pump failing?

I replaced the OEM oil pump about 7 years ago and it has served me for the last 35 years that I couldn't give up this lovely tractor.

Any suggestion from savvy members in here will be much appreciated

Jkk
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I would say that there is a good chance the somewhat new pump has failed. Especially if it was being starved of fluid due to sludge build up, that is never a good thing for a pump. Also evidence of poor pressure is another indicator.

 

[jkk04]

I would say that there is a good chance the somewhat new pump has failed. Especially if it was being starved of fluid due to sludge build up, that is never a good thing for a pump. Also evidence of poor pressure is another indicator.

Thank you for responding.

I thought the pump failed too but want to make sure before splitting the tractor which is a big job for especially old age 70

Any other possible failures other than the pump failed?

Also, I was surprised that there was a lot of sludge in the sump pan in 7 years and running time only around 150 hours.

Does it cause bad transmission fluid or???? I put the universal tractor trans/hydraulic fluid from the tractor supply.

Thanks

Jkk

 

[loggin]

Thank you for responding.

I thought the pump failed too but want to make sure before splitting the tractor which is a big job for especially old age 70

Any other possible failures other than the pump failed?

Also, I was surprised that there was a lot of sludge in the sump pan in 7 years and running time only around 150 hours.

Does it cause bad transmission fluid or???? I put the universal tractor trans/hydraulic fluid from the tractor supply.

Thanks

Jkk
View attachment 858329

Well I cannot say for certain that it is the pump but there is a good chance.

That sludge does look quite dark. Did you pass a magnet through it to see if there were any metal shavings in it?

I don't know about the brand of fluid you are using but the older machines were typically not that picky when it came to hydraulic/trans fluid.

 

[jkk04]

The problem is that the service manual does not clearly describe what lower pressure means and what parts need to be replaced.

Splitting the tractor is quite a big job for an especially retired old guy.

That is the reason I need to pinpoint what needs to be done before splitting the tractor and need to be advised by savvy people.

Thanks again.

John

 

[jkk04]

Well I cannot say for certain that it is the pump but there is a good chance.

That sludge does look quite dark. Did you pass a magnet through it to see if there were any metal shavings in it?

I don't know about the brand of fluid you are using but the older machines were typically not that picky when it came to hydraulic/trans fluid.

Yes.
The fluid passed through the magnet and didn't see any metal shaving nor pieces while cleaning the filter and pan.
Thanks

 

[loggin]

The problem is that the service manual does not clearly describe what lower pressure means and what parts need to be replaced.

Splitting the tractor is quite a big job for an especially retired old guy.

That is the reason I need to pinpoint what needs to be done before splitting the tractor and need to be advised by savvy people.

Thanks again.

John

I completely understand, splitting a tractor is a big job!! I am sorry I cannot be of more help but I just don't know your model well enough. Hopefully someone else can chime in here.

 

[5030]

Hopefully, after you go through repairing it, you won't let the fluid sit inside for 7 years without changing it and I hope you don't do that to your vehicle either. That stuff looks plain nasty to me.

 

[jkk04]

Hopefully, after you go through repairing it, you won't let the fluid sit inside for 7 years without changing it and I hope you don't do that to your vehicle either. That stuff looks plain nasty to me.

Actually I am not that lazy but I take care of all equipment more than needed.

This case is a special that the owner manual said replace the fluid every 750 hours.

The fluid has been changed 7 years ago but operating hours are only 150 or less as stated above.

That makes me strange.

Thanks

 

[5030]

I have an adverse thing about using cheap TSC fluids as well. You get what you pay for and from the looks of that sludged up pan, I'd say you did.

Looks to me like the fluid you used had severe component dropout, probably from heat and cool cycles coupled with the cheap fluid.

If I was using any powered tractor as infrequently as you did, I'd be changing the fluid and filters a lot more often that the owners manual specified, at least twice as often, especially if using cheap fluid, something I never do in the first place. All my tractors ever see is full synthetic Chevron fluids. No0t a cheap date by a long shot but then having to rebuild because of fluid related issues is never cheap either.