# Ford 6600 PTO will not engage



## CAEMI (Mar 17, 2009)

My Ford 6600 PTO has become balky and sometimes will not engage when I pull up the lever. Does anyone have any suggestions on where to start on this? I need this machine to bale hay tomorrow and I'm worried it will give me trouble just when I need it most.


----------



## BigT (Sep 15, 2014)

Hello CAEMI, 

Welcome back to the Ford/New Holland tractor forum!

PTO CLUTCH WILL NOT ENGAGE (OR SLIPS UNDER LOAD) could be caused by:

A. Low rear axle oil level.
B. Failure of hydraulic pump.
C. Failure of connecting pipe.
D. Control valve stuck open.
E. Control valve spring broken.
F. Cast iron sealing rings on clutch broken.
G. Clutch piston sealing rings leaking.
H. Brake piston sealing rings leaking.


----------



## CAEMI (Mar 17, 2009)

BigT said:


> Hello CAEMI,
> 
> Welcome back to the Ford/New Holland tractor forum!
> 
> ...


a. The oil level is down a tad...not enough that I'd add oil but I'll do that first.
b. The pump seems fine. Remotes work fine, as does the FEL.
c. What is the connecting pipe?
d. & e. Which control valve - the remotes?
f. & g. The clutch seems perfect. How would I diagnose broken rings?
h. Now this is interesting...I noticed some oil leakage below where the brake plunger enters the housing. But it ONLY leaked once...and that seemed related to relieving the pressure off the hydraulic lines after the engine was shut down and I was detaching the haybine. I relieve the pressure in order to remove the couplers. I've done this many times but never before have I observed a leak anywhere.


----------



## BigT (Sep 15, 2014)

CAEMI said:


> a. The oil level is down a tad...not enough that I'd add oil but I'll do that first.
> b. The pump seems fine. Remotes work fine, as does the FEL.
> c. What is the connecting pipe?
> d. & e. Which control valve - the remotes?
> ...


____________________________________________________________________

a. Good. The rear end is your hydraulic fluid reservoir. 
b. Your tractor has dual pumps. The remotes, lift, and FEL are driven by the big pump. The small pump drives the PTO clutch pack/brake and also the dual power clutches (if you have dual power).
c. The pipe between the PTO control valve and the PTO clutch pack. The PTO control valve is a hydraulic valve that provides fluid to the PTO clutch pack. There are pressure checks that you can do to determine if your small pump is providing enough pressure. 
d&e. The PTO control valve.
f&g. You'll have to pull the PTO clutch pack to determine if you have broken rings.
h. If you have dual power, there are DP hydraulic clutches driven by the small pump that can also leak. I failed to mention this potential source of leaks in my original post. 

CAEMI, You need to get a shop/service manual for your tractor. I think an I&T manual might be sufficient ($30-$35). At least to get started. It will show you how to do pressure tests on the PTO clutch system.


----------



## CAEMI (Mar 17, 2009)

BigT said:


> ____________________________________________________________________
> 
> a. Good. The rear end is your hydraulic fluid reservoir.
> b. Your tractor has dual pumps. The remotes, lift, and FEL are driven by the big pump. The small pump drives the PTO clutch pack/brake and also the dual power clutches (if you have dual power).
> ...


BigT: Thanks for the clear explanation. I'm working on your ideas. I have the Ford factory manuals as well as the I&T manual. I have not needed them until now...but I'll study up on the problem as soon as I'm done baling and can lay the machine up for a while.

I do have Dual Power (love that feature...use it all the time). Regarding pulling the PTO clutch pack...please don't tell me that means the tractor must be split. 

And thanks again for the on-point guidance.


----------

