john deere 445 one cylinder misfiring

phil burckhalter · Jun 4, 2013

hi everyone, hoping someone might have the answer, i have a john deere 445 liquid 22 hp kawasaki. it started missing on the left side. when first started cold, runs good for about 5 seconds then starts missing. i don't have a coil tester, but the spark seems strong. compression seems ok. i changed the head gasket, and did the leak test, didn't drip any gas in ten minutes. the plug becomes black but not wet. is it possible i have a gas pressure issue. any thoughts would be most grateful
phil

Sundancer268 · Jun 4, 2013

My 445 has done that for years. I have replaced both ignition coils over the years and that seems to help for a short time. Some times I have to let it run on one cylinder for a few minutes and then it will settle out and run great. I wish I had the answer for both of us. Maybe some one will know where to go from here.

phil burckhalter · Jun 5, 2013

hi, yesterday i checked again, and i noticed both are firing, but both are running very rich, where both plugs are black, but they are firing somewhat because they are not wet, being fuel injected i am guessing the computer is running it very rich for come reason. any clues?

Sundancer268 · Jun 5, 2013

I would check the temperature sensor for a proper reading. If it is like most sensors it will have a specification saying XXX Ohms @ XXX degrees. This will most likely be in the form of a chart and will show if the resistance goes up as the temp rises or if the resistance goes down with a rise in temperature. If the computer thinks the engine is colder than it is it will keep supplying a richer mixture until the engine reaches operating temperature which it will never do. I believe the 445 has two temperature sending units with one feeding the computer and the other the gauge. It is a fairly primitive fuel injection system compared to an automobile fuel injection computer. If you are still having problems maybe someone can look in the JD service manual. I can not access mine until this coming weekend.

phil burckhalter · Jun 6, 2013

thanks for the information, i don't have the equipment to test it, but it does lead me to an area i could very well be. runs for about 5 seconds good then starts loading up.being that it is a old style fuel injection, i don't believe it's in the carb. if not the sensor, i am hoping its not the computer, also not sure how to test that. no codes or flashing on the dash where i heard that sometimes will happen when some of the sensors are acting up.

Sundancer268 said:
I would check the temperature sensor for a proper reading. If it is like most sensors it will have a specification saying XXX Ohms @ XXX degrees. This will most likely be in the form of a chart and will show if the resistance goes up as the temp rises or if the resistance goes down with a rise in temperature. If the computer thinks the engine is colder than it is it will keep supplying a richer mixture until the engine reaches operating temperature which it will never do. I believe the 445 has two temperature sending units with one feeding the computer and the other the gauge. It is a fairly primitive fuel injection system compared to an automobile fuel injection computer. If you are still having problems maybe someone can look in the JD service manual. I can not access mine until this coming weekend.

BBO · Aug 4, 2013

phil burckhalter said:
i have a john deere 445 liquid 22 hp kawasaki. it started missing on the left side.

Did you ever find the problem?
How much oil is in the air filter tray when you open it?

phil burckhalter · Aug 8, 2013

hi, what i found out actually, both sides were missing, it ran good enough to even cut grass, but i could hear it missing, running very rich. not terrible, but a couple times a second. nobody had a clue, so i gave up and took it to john deere. i had purchased the tractor only a few weeks prior, so i did not know it's history. what john deere found out was someone had messed with all the wiring, and polution. they wired it as it was supposed to be, and then it ran fine.
when i first got the tractor, it was very hard starting, wouldnt stay running till it was warmed up, and ran, lousy even when it was warmed up. so i took off the left head and found it had a blown gasket. i noticed that someone had taken off the head cover, because they broke off the one tab on top. so either they were in the engine and trying to figure out why it wasnt running good. after replacing the head gasket, it started right up, would run good for 5 seconds then started missing.
as far as the oil in the air filter tray, that was totally dry.
what problem are you having with yours?

BBO · Aug 8, 2013

phil burckhalter said:
... as far as the oil in the air filter tray, that was totally dry.
what problem are you having with yours?

My rings were worn and I had some serious blow by coming back into the carb.
I have since replaced the rings, but even still I have some small amount of oil in the tray. Mine has about 1130 hours.