1948 Ford 8N hydraulic issues

[Deege8n]

Hi everyone. I am having issues with my hydraulics. I have searched high and low here and cannot find anyone with a similar issue.

My tractor can lift my box scraper and hold it there. It will stay in place during transport and won't drift downward. It then lowers just fine. Here's the issue. It won't lift the box scraper back up unless I disconnect it and lower the bars all the way down. Then I raise them back up, attach the box scraper, and it raises it all the way back up again.

I'm stumped. Any help is greatly appreciated.

 

[JMOR]

Try it with the top link disconnected. Be sure you are inPOSITION control mode and not in DRAFT control mode.

 

[Deege8n]

(quoted from post at 19:44:11 05/27/23) Try it with the top link disconnected. Be sure you are inPOSITION control mode and not in DRAFT control mode.

If the top link is disconnected and it works, are you thinking it's bound up with top link?

 

[R Geiger]

(quoted from post at 20:52:20 05/27/23)

(quoted from post at 19:44:11 05/27/23) Try it with the top link disconnected. Be sure you are inPOSITION control mode and not in DRAFT control mode.

If the top link is disconnected and it works, are you thinking it's bound up with top link?

he top link pushes against the yoke which pushes against the controls inside.

 

[JMOR]

(quoted from post at 22:52:20 05/27/23)

(quoted from post at 19:44:11 05/27/23) Try it with the top link disconnected. Be sure you are inPOSITION control mode and not in DRAFT control mode.

If the top link is disconnected and it works, are you thinking it's bound up with top link?

ot bound up but linkage worn/bent/broken/etc.

 

[Tim PloughNman Daley RIP]

System is worn and needs rebuild. Email me for my document on 8N HYD REPAIR. Plan on pulling the entire pump for the rebuild. 8N Operator's Manual, I&T FO-4 Manual, and
MPC all required.

Tim Daley (MI)

 

[Deege8n]

(quoted from post at 05:31:03 05/28/23)

(quoted from post at 22:52:20 05/27/23)

(quoted from post at 19:44:11 05/27/23) Try it with the top link disconnected. Be sure you are inPOSITION control mode and not in DRAFT control mode.

If the top link is disconnected and it works, are you thinking it's bound up with top link?

ot bound up but linkage worn/bent/broken/etc.

The actual top link is brand new. Does the top link actuate something?

 

[JMOR]

inside the big spring attached to top link rocker is a rod called draft plunger, correct name I think , and it ultimately connects to draft linkage and can provide input to pump hyd control valve

 

[Deege8n]

(quoted from post at 05:54:37 05/28/23) System is worn and needs rebuild. Email me for my document on 8N HYD REPAIR. Plan on pulling the entire pump for the rebuild. 8N Operator's Manual, I&T FO-4 Manual, and
MPC all required.

Tim Daley (MI)

I'm going to take the top cover off, but I'm thinking you're right. I inspected and found that oil is pouring from the top out of the piston when trying to lift from a position where the box scraper would be on the ground. When the arms are all the way down, it'll lift. I found another forum that advised it could be the piston is worn on that particular spot, which is why it has no problem holding the scraper up or lifting from low position, but will not go up at the level where box scraper is on ground.

I'll report back what I find with some photos.