Hydraulic linkage not moving

Aquiterio

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Hi Guys
I've been making a general service on my Mitsubishi MT1640 (K4A engine), and everything has been flowing quite ok.
Some minor hic-hops because i could not find the proper manuals but, anyway, it's been going.

Now, after changing the transmission oil and clean the filter, the 3 point linkage hydraulics are not moving at all.
I have to say that, even with the very old-used previous oil, it was working quite well.
But wit this new one (80W90 gear oil), nothing happens.

The only steps were:
- Drain old oil
- Remove, clean and assembling the filter
- Add new oil
- Run the tractor engine by 15min

I've checked the oil level and it's a bit over the limit (removing the side plug, it flows out).
I can drain it but i would prefer to don't waste it..

My only ideas:
- Too much oil, somehow doesn't allow to work
- Something wrong when assembling the oil filter (i'm afraid about the gasket, maybe wrongly assembled)

Anything else to check?
Thanks in advance
 
80/90 gear oil is NOT for a hydraulic/transmission system....way too thick! You need hytran fluid. You must dump all that 80/90 oil which will drain slow, so allow 24hrs to drain it well. Use clean original containers so you might be able to use it appropriately.
 

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80/90 gear oil is NOT for a hydraulic/transmission system....way too thick! You need hytran fluid. You must dump all that 80/90 oil which will drain slow, so allow 24hrs to drain it well. Use clean original containers so you might be able to use it appropriately.
I can agree with you but the info that i got on the tractor label is to use a SAE80 type oil.
Bellow the label on the tractor and the exact oil i used.
What am i missing?
 

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I noticed from another post that one Satoh tractor does use 80w oil for it's transmission, BUT it has a small separate oil supply for the hydraulic system and uses 10w to 20w for it. Typically a transmission without a consolidated hydraulic system does not have a filter. So I'm thinking when you cleaned that filter you drained the separate hydraulic oil. Many manuals are vague. If you recheck that filter and find it doesn't have any oil at all in it now, then it likely has it's own fill point, but I have zero knowledge of your tractor. If there isn't oil in that filter now, you shouldn't run tractor until you figure this out. I wish I could tell you more.
 
I noticed from another post that one Satoh tractor does use 80w oil for it's transmission, BUT it has a small separate oil supply for the hydraulic system and uses 10w to 20w for it. Typically a transmission without a consolidated hydraulic system does not have a filter. So I'm thinking when you cleaned that filter you drained the separate hydraulic oil. Many manuals are vague. If you recheck that filter and find it doesn't have any oil at all in it now, then it likely has it's own fill point, but I have zero knowledge of your tractor. If there isn't oil in that filter now, you shouldn't run tractor until you figure this out. I wish I could tell you more.
I made a radical move, i remove all oil from transmission..
I started from the filter and it was full of oil and draining normally, then from the main drain, to be faster.
I re-check the seals position, assemble everything, put again the oil and... nothing, no movement... :(

If no ideas, i have to bring it to service shop...
 
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