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Front PTO enagement 322

1325 Views 17 Replies 12 Participants Last post by  geb63619
I recently bought a 322 and have been wondering why the front PTO does not engage until at least 1/2 throttle. I flip the switch at low throttle, the indicator lights up. Then as I increase the throttle the PTO kicks in. Once the PTO on I can lower the RPM again and it stays in engaged. I though I found the problem earlier this week when I notice some wires had been badly damaged at one point by the deck belt. Unfortunately it behaved the same way after a careful splicing and soldering. My other thought was do I have a voltage problem, because when the headlights are on the PTO needs an evener higher throttle position to engage. Note the alternator light never goes on during operation. Any thoughts would be appreciated.
Thanks Pete
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Not sure but i would check the airgap on the pto clutch. Not sure on spec, Im sure somebody will chime in, I have mine set at .015.
Does the engine bog down? Is the belt squealing between PTO switch flip and the deck starting?

I set the PTO clutch gap at 0.016". I believe specs state 0.015-0.017"
The engine boggs down very briefly until the governor increases the throttle. There is also a brief chirp in the belt. Today I got mixed results - after engaging the PTO multiple times at high rpm I was able to engage it at low rpm a few times. Now it is back to the way it was. I need to look at wiring diagram I'm wondering if there is an intermittent relay in the circuit somewhere. I also need to check the manual on how to check the clutch gap this week.
FYI , mine had a similiar problem and the issue was carburetor adjustment. Review this thread:


May help, may not....
The PTO needs the air gap adjusted and set correctly.

When the air gap is in the proper range the PTO engages easily at the proper low RPM's.

You have to increase the throttle to get some extra power for the disc to cross the extra wide gap that it most likely has now.

The pto disc does wear over time and vibration can be an issue also. Get some feeler guages and sit down with them and a wrench. You'll be happy you did. Your manual should have the procedure.

Try to avoid engaging the PTO at full throttle as this just causes extra wear and shock to the system.
Thanks for the input. It turns out the gap was about 0.04" at one of the screw locations and in the high 20's in the other two locations. I set it to 0.017" - my manual called out 0.018". The clutch engages nicely now, but there is a high pitch whine. I'm not sure if it is the bearing or vibrations from parts of the clutch plate.
My 93 455 has 1100 hrs and runs strong. The issue is starting it. A month ago it began to almost stall after starting it and in the last week it now stalls after starting. I will then go the starting sequence again and it starts with no problem and remains running.

Prior to this it started first time no problem even in the dead of winter.

I am concerned this is the sign of something bad beginning. Any thoughts on what it could be?

Thanks, Robert
How old is the fuel in the tractor and have you changed over to Winter blend yet? Roger
Fuel is fresh, it never sits for long. My recent fuel up was a week ago.
Change the fuel filter.
Replies to Scott, Alan and Robert G

I changed my fuel filter in the spring, but can swap it out. Cheap fix if thats the problem

Not sure how to test the glow plugs or the relay.

Once it is running the RPM's are fine, it only stumbles or stalls on the initial start and is fine after that.

The problem is the glow plugs. When you turn the ignition switch on, the glow plug idiot light stays on for about 10 seconds; however the glow plugs operate for about 45 seconds. Glow plugs warm the air in the cylinder for better combustion while starting and until the combustion itself warms the cylinder.

Another problem is that there is a voltage drop caused by the electrical connections. Refer to this thread I wrote about my 332. A 455 would be the same.


When it is cold, I let the glow plugs go through a couple 30 second cycles before attempting to start.

Whenever I buy another 455, I usually just change the glow since newer ones will work better. A simple ohm meter test can be done to check them.

George of Buford

PS Right now I own four 455's and speak from experience.
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Indeed, the problem is likely that one or more glow plugs is dead. To test a glow plug, take the wire off the top and check resistance from the center electrode to ground. Resistance should be in the 1 ohm range, but they typically fail as an open circuit, as long as you have continuity you're probably fine.


The JD part # for the glow plugs is M87919 which cost around $43 each. I cleaned the paint off an old one and found the OEM part is an NGK Y702R. You can get them from ngk.com for around $25 each.

Changing glow plugs is about like replacing spark plugs. If one is bad, I go ahead and change all three. If one failed, another will probably fail soon. The old ones are usually coated with soot that insulates the tip. The last 455 I bought had 1800 hours and was a 1996 model with the ORIGINAL glow plugs. That is 17 years of service. If I change them now, I will never need to do it again.

Another poor cold starting cause is poor compression. My oldest 455 has around 3000 hours and starts much harder than my newer ones. I did a compression check and found it is a little low. The engine runs great but is hard starting in cold weather.

George of Buford
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If you have a bad glow plug they crank and crank before they even think about firing. Just like Scott said when its cold push the throttle up about half and see what it does before you go threw the trouble changing anything out.

Instead of using mother Deeres $40 glow plugs go to amazon.com and buy the Y103K Click Here

There are other threads here on WFM talking about these glow plugs I have at least 3 of my tractors running them for 4-5yrs now with zero issues.

You can change all the plugs out for under $27 can't beat that
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