Why does my FEL go up when I go to float position?

[Tractorbaja]

You have a pipe "from the pump" and a pressure in hose? So you have 2 pressurized inputs?

I have a pipe from the hydraulic pump to the 3 point lift housing and a hose from the aluminum block that goes to the "IN" side of the valve.

 

[CADplans]

If the hose from the valve returning flow to the tractor is feeding the 3PH,, this is the problem.

An open center hydraulic circuit MUST have a power beyond valve, if more than one function is being supplied from the tractor hydraulics.

The real problem of not using the power beyond port is if you ever operate both functions at the same time.

Actuate the three point with a heavy attachment, and make the loader go up,, both at the same time.
If you do that, the pump will see the pressure requirement of BOTH at the same time, added together.
What happens is the seal blows out of the pump because the pump was required to produce 4,000 psi, instead of 2,000psi.

The power beyond return line insures the pump is not damaged by this pressure doubling.

 

[LD1]

IF you only have 6 hoses at the loader valve, you do NOT have PB.

IF the tractor is an open center system (which it is)...this is the issue. The thing is currently plumbed incorrectly, as it was before. Thus you have the same issue you had before. All you did was add a 3rd but the problem remains.

Is this a factory OEM loader or an aftermarket?

Hard to troubleshoot/explain/and diagnose over the internet without knowing your level of knowledge and mechanical aptitude, and without seeing the "whole" picture. I all for a DIY mentality......but I am thinking it would be money well spent to find a local tractor mechanic that has half a brain to take a look