Oil & Fuel John Deere 445 weak under load

[snapline]

I have had my JD for years with no major issues at all!
Last few days I am having a problem with the engine idle under load.
At first it seemed as if I was running with only one [1] cylinder firing. Thought perhaps a loose spark plug wire [happened one time before]. Not the cause this time.

Engine got worse and would not run at all and was misfiring also. Thought perhaps bad gas or bad fuel filter. Replaced the fuel filter and drained off the gas in the tank. Old filter seemed okay but replaced anyway.

Added conditioner to remove any water from fuel system with some fresh gas and the engine ran well after a few minutes with no load. I let the tractor idle for about 15 minutes at high throttle to 'flush out' the fuel system.
Tractor ran well at this point. Turned on mowing deck [60"] and the tractor still ran ,BUT not at full capacity. Power to mowing deck is reduced for sure although she still will run. Had to turn off the deck when riding up hill!

Sounds like fuel starvation, BUT not sure where to look next!
900 hours on the tractor. Overall in very good shape!

Would appreciate any thoughts.
Thanks!

 

[beenthere]

:welcome: to the forum.

Not sure I am following when you say "problem with the engine idle under load". To me "idle" means low rpm with throttle back. Later you mention "idle for about 15 minutes at high throttle".
Your defn of idle must be different. Maybe I can sort it out.

Have you had the compression checked? Has your valve lash been adjusted?

 

[snapline]

Thanks for the response.

Maybe I should state the issue this way.
Engine idles fine now when the tractor is just sitting with engine on.
If I take it for a ride [at full throttle] , no issues.

When I switch on the mowing deck [60"] under full engine throttle, the mowing deck does not run at the same speed it use to. It is running slower [rpm's] and does not have the cutting power it use to have. It seems as if the engine does not have the same amount of torque [power] it had last week prior to this issue. I was thinking fuel starvation.
Changing oil and oil filter. Oil was dirty and in need of a change anyway!

Checked gap on both plugs, one was at .030 and the other was at .032
Reset the one plug that read .032 back to .030 as specified in owner's manual.

Also replacing air filter and foam cover for air filter with new!
Also draining engine coolant and replacing with new.
Once completed tomorrow morning I will report back.

Meantime, I have no clue as to what 'valve lash' is!

Again my thanks. Any other thoughts after my modified description of the problem would be appreciated.

 

[mfreund]

Did you take off the mower deck? Could you have a issue with the deck causing the engine to work hard?

 

[snapline]

Yes I did remove the deck.

Cleaned it up real good and sharpened the blades [balanced too] since I had the deck off. Grease fittings all okay on the deck so I believe that is not the issue.

As stated earlier I am right now in the process of replacing oil, etc.

Will get back with results after completion of maintenance steps.

Thanks for the response. Good thought, I thought the same and that is why I removed the deck to check all. I serviced the deck at the beginning of my use season and all was good then with the deck and it is still good.

 

[beenthere]

When I switch on the mowing deck [60"] under full engine throttle, the mowing deck does not run at the same speed it use to. It is running slower [rpm's] and does not have the cutting power it use to have. It seems as if the engine does not have the same amount of torque [power] it had last week prior to this issue. I was thinking fuel starvation.
Changing oil and oil filter. Oil was dirty and in need of a change anyway!

Sounds like the issue, as mfreund suggested, is related to the deck or maybe the PTO drive.

Are you changing the hyd. transmission oil when you said it was dirty? or referring to the engine oil? I don't see this as an engine problem, so when the deck is off and the PTO engaged maybe you can determine if the same overload conditions show up. Those conditions as mentioned in OP

Engine got worse and would not run at all and was misfiring also.

 

[snapline]

Thank you.
I was referring to the engine oil when I was stating I was changing the oil.

I have completed following.

Changed ENGINE oil and ENGINE oil filter.
Replaced Engine coolant with new.
Replaced paper air filter for engine with new.
Replaced foam liner for engine paper filter with new.

I HAVE NOT replaced fluid in the hydraulic transmission, BUT will do so and at the same time replace the filter for same.

After completing above, ran engine and it runs well at full throttle. On low throttle or 'idle' I noticed that the battery charging light came on so I will run for awhile at full throttle to charge battery. Once cool I will replace hydraulic oil and filter.

Engaged mower deck and it ran BETTER than before, BUT still not running like it use to. Seems slower and running at a slower RPM than before.

It should be noted, that I did put some 'GUMOUT' fuel injector cleaner in four gallons of fresh gas and that has not had a chance to run thru the engine yet.

 

[Republic of Texas]

Had similar symptoms on my 850. Turns out, it was the hydraulic/transmission oil filter. Blocked at around 98%. (Shift boot cover had been missing for years before I bought it.)

I would almost bet it's the filter. If not, check your hydraulic/transmission oil pump.

 

[snapline]

Thank you very much for the info on the hydraulic oil filter.

I was going to change it last night [have a replacement on the shelf] , but I am a quart low on fluid for the transmission. Did not want to go forward until I have enough oil to do the refill in complete.

I will post once I complete change of filter and oil.

Hoping this will be the fix.

THNAKS again!

 

[snapline]

UPDATE!!
I replaced the transmission oil and transmission oil filter this morning.
It was in need of replacement, BUT this has not solved my problem.

I am still thinking it is a fuel flow issue. When at idle the engine runs perfectly. When I move the throttle to full of max position and increase pressure on the gas pedal, i.e. asking for more power from the engine, the response is sluggish.

I find that there is an additional fuel filter, JD # AM117116. Looks to me like it attaches to the bottom of the fuel pump. Can anyone direct me as to where to find the fuel pump on this guy? Sounds like a dumb question, but I have never worked on this 445 except for general preventive maintenance.

Must be near the fuel tank I guess but would appreciate some directions.
I am also going to look at the Governor Linkage. Wondering if there is some sort of adjustment there?

This engine runs perfectly while sitting and at idle. It seems to be not getting enough fuel under load!!!!!!!!!!!!!!!!!!