674 After Hydraulic filter change, no pressure

Hello, first post here.
I have a 674 and recently it has been hard to steer and the light on the dash has been lighting up when the PTO is engaged.

I figured I would change the hydraulic filter. I drained the fluid from the bottom of the case. 7-8 gallons came out. I replaced the filter and cleaned the screen (the screen wasn't really dirty). I only had about 6 gallons of fresh fluid (Rando 36). After start up I had no pressure anywhere. Even let it idle for about 30 minutes.

Do I just need more fluid?

Thanks.

Hi, below is suggestion from Bernard who was a CaseIH mechanic:
Capacity is 9 gal and over fill by another 3 to 5 will not damage anything.
Make sure the filter is toward the MCV valve and the stainer is in the cover.
The best way to bleed the hydraulic system is to loosen the pipe below the hydraulic filter, place a clean bucket under to catch hydraulic fluid and run the engine until hydraulic fluid comes out.

The light on the dash indicates low pressure on the transmission lube pump. Could be a faulty sensor under the seat or low hydraulic fluid level. The newer models have eliminated this sensor.
Hard to steer can indicated the MCV priority valve is sticking. Sometimes dirt can cause the valve to stick and sometimes by activating the remote control lever until you hear the hydraulic relief valve squeal will dislodge the dirt.
If the remotes and 3 pt work good then most likely the problem is a sticking flow divider in the MCV valve. If 3pt and remotes are weak also then could be weak pump. The flower divider takes the 12 GPM output of the hydraulic pump and splits it into 3 GPM for PS, PB and oil cooler and 9 GPM for 3pt and remotes.

Hope this helps
JimB

I haven't done this in awhile, so I'm trying to remember the specifics. You'll have to remove the plug under the filter on the bottom of the MCV body. I think it takes a 1 1/4" wrench. Remove the plug, then let the spring fall out. There may even be a valve along with the spring. Put the bucket under the hole and start the tractor. After a few seconds, oil will come flowing out. Shut off the engine and put the parts back in the MCV body. When you start the tractor the next time, you should have hyd. pressure. I have to do this every time I change the filter. They say its because the pump is worn and can't prime itself. Hope this helps!

JimB2 and shadetree,

Thanks for your replies. I will give them a try as soon as I can.

(quoted from post at 10:21:37 10/06/08) I haven't done this in awhile, so I'm trying to remember the specifics. You'll have to remove the plug under the filter on the bottom of the MCV body. I think it takes a 1 1/4" wrench. Remove the plug, then let the spring fall out. There may even be a valve along with the spring. Put the bucket under the hole and start the tractor. After a few seconds, oil will come flowing out. Shut off the engine and put the parts back in the MCV body. When you start the tractor the next time, you should have hyd. pressure. I have to do this every time I change the filter. They say its because the pump is worn and can't prime itself. Hope this helps!

Click to expand...

That was it!!! Works great now!!

Thanks a lot!!!