Oil & Fuel John Deere 790 questions

[Decker790]

I have a 2001 john Deere 790. I really love this tractor. It is perfect for my needs on my 5 acre wooded lot. I purchased it this past spring and enjoy every minute of it. It only has 600 hours on it and runs great. Now that it has been getting colder out I have noticed a few things. During start up it does pass some blue smoke for a bit. Also when just moving some things around the yard without any load on the motor I have noticed some discharge from the exhaust pipe. Leaking out of top. Not much but enought to drip down pipe Looks tan in color and smells a little like oil and deisel. Hard saying its exhaust right!!! The blue smoke stops right after start up. I know this is typical that it is colder out now Just wondering about discharge??? First time I noticed it and no signs on pipe of this happening before. It is very foggy and a lot of moist air today. Thanks for all your help!!!! First time poster and first time owner.

 

[sixdogs]

I have a 790 and don't start in the cold very often but can't recall what you mention. There does appear to be some condensation I see in the exhaust stack but nothing that seems unusual. The oil isn't overfilled is it? It's easy to do on the 790.

 

[Decker790]

my oil level is a little high. About 3/8" over full on dipstick. I didn't think that would be big problem. Yeah mine is hard starting when cold also. Everything else looks good. Clean air filter. I have been checking the oil frequently since I first stared seeing this about a month ago. No drop in oil level. It pops some blue right during cold start, it's just the discharge that I saw today that really got me thinking.

 

[sixdogs]

I'm thinking it's all normal but we need some others to help out here. Overfilling the oil could be an issue.

 

[AKfish]

I have a 2001 john Deere 790. I really love this tractor. It is perfect for my needs on my 5 acre wooded lot. I purchased it this past spring and enjoy every minute of it. It only has 600 hours on it and runs great. Now that it has been getting colder out I have noticed a few things. During start up it does pass some blue smoke for a bit. Also when just moving some things around the yard without any load on the motor I have noticed some discharge from the exhaust pipe. Leaking out of top. Not much but enought to drip down pipe Looks tan in color and smells a little like oil and deisel. Hard saying its exhaust right!!! The blue smoke stops right after start up. I know this is typical that it is colder out now Just wondering about discharge??? First time I noticed it and no signs on pipe of this happening before. It is very foggy and a lot of moist air today. Thanks for all your help!!!! First time poster and first time owner.

Your engine's got the "cold slobbers"! Nothin' to get overly concerned about. Cover up the radiator with some cardboard, etc. and the engine will warm up faster to operating temperature and stay there when working in cold conditions.

AKfish

 

[RoyJackson]

Yep, AKfish nailed it...
I had a 790 (2003 model) for 5-6 years...great little tractor. I'd get the smoke, but not the dribbles (not that I can recall, anyway).

3/8ths over max is too much oil...that's not good and I do suggest you drain some out. Too much oil in the sump can result in foaming of the oil...that actually reduces the lubrication of the bearings. There were three engines in the 790 over the course of the production run. Your engine should take about 4 quarts (4.3, IIRC). Best to leave that oil a bit low (on the crosshatched area) then too high.

Also, when you idle your tractor, keep it around 1500 RPM. 790's are very frugal with fuel and you won't notice any added consumption at 1500 RPM.

 

[Tx Jim]

Your engine's got the "cold slobbers"!
AKfish

Also known as "wet stacking". If you put the engine to work at operating temp problem should go away.

 

[Decker790]

Thanks for your help guys!!! I will try draining some oil out and keep the eng temp up and rpms. It makes sense since I was just moving some attachments around in my shed. Getting ready for winter. No load and slower idle etc. thanks again.