[OutOfApplication]

A new tractor, new problems. I just picked up a JD 445 it starts right up and appears to run well, but when fully warmed up it's stumbling & smells rich. Apparently I didn't fully warm it up during the test drive before I bought it. Doe! I was happy to see it cold start so well. I'm going to dive in shortly to see what I can figure out, but what are the usual suspects for this engine?

thanks!

 

[jmb6420]

I'd start by checking valve clearance.


Mike in Okla

 

[ironpony]

points and condenser or electronic ignition?

 

[OutOfApplication]

I'd start by checking valve clearance.


Mike in Okla

Hi Mike good suggestion. I just checked and made a slight adjustment to one valve, but that's not the problem. I did a compression test and I get 220 PSI in both cylinders, so that's great. Spark plugs are black, one worse than the other. I'll order some and change them out, but to me this thing feels like the choke is on. I know it's efi so there is no choke, but does this system have a feedback From an O2 sensor or something?

Thanks

 

[OutOfApplication]

points and condenser or electronic ignition?

It's EFI so I'd assume electronic ignition. I don't know much about this engine yet. Just bought it and never had one before.

 

[jmb6420]

It's all run by the computer that receives signals from throttle sensor,air temp sensor, coolant temp sensor and others. I'm not sure what to tell you to check next. I'm gonna follow and see what done of the more knowledgeable guys have to say. I did check the manual and can't find anything in the trouble shooting section on your problem. FB has a Deere 4x5 group also that has a lot of information.


Mike in Okla

 

[QStott]

My 445 ran fine, but was down on power when engaging to mower deck. It was only running on one cylinder. One coil had died. I was surprised at how well it ran.

 

[OutOfApplication]

Well QStott,
That's the issue. One dead coil. Runs shockingly well on 1. Can't wait to see how well it runs on 2. When I pull the left plug no change in rpm, pull the right one it dies immediately. I swapped the plugs and the same behaver, so it's not the plug, it's the coil. I do see pulsing on the signal wire to the coil with my scope, so I'm 100% sure it's the coil. I'll probably just replace both since they are probably the same age.

 

[jmb6420]

Glad you got it figured out. Let us know after you install the new coils.


Mike in Okla

 

[QStott]

Great ! My plug wire boots were a little brittle so I replaced them at the same time. It is amazing how well they run on one cylinder .

 

[OutOfApplication]

I put two new coils & boots and it runs great now! New plugs still on the way, but clearly the plugs are fine.