Engine oil capacity of JD790?

   / Engine oil capacity of JD790? #1  

sixdogs

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My JD790 is supposed to take 4.3 quarts of engine oil but that amount goes way over the full line. The oil get drained when hot and I let it go for maybe 15 minutes to get as much out as possible. Filter change too. Still, I'm full at maybe 4 qts. So is the book wrong on the amount or the dipstick wrong?
 
   / Engine oil capacity of JD790? #2  
My JD790 is supposed to take 4.3 quarts of engine oil but that amount goes way over the full line. The oil get drained when hot and I let it go for maybe 15 minutes to get as much out as possible. Filter change too. Still, I'm full at maybe 4 qts. So is the book wrong on the amount or the dipstick wrong?

Have you started your engine for a few second after adding the oil, to fill your filter? Was not mention in your post.
 
   / Engine oil capacity of JD790?
  • Thread Starter
#3  
Have you started your engine for a few second after adding the oil, to fill your filter? Was not mention in your post.

Yes I do.
 
   / Engine oil capacity of JD790? #4  
The manual does mention ''approximately 4.3 quarts''. It would not be the first time that a manual is not dead on. I don't know how much overfill you are, but for ease of mind, you could ask someone with a 790 to measure their dip-stick and compare. In the mean time, might not be a bad idea to bring the level down a bit.
 
   / Engine oil capacity of JD790? #5  
My JD790 is supposed to take 4.3 quarts of engine oil but that amount goes way over the full line. The oil get drained when hot and I let it go for maybe 15 minutes to get as much out as possible. Filter change too. Still, I'm full at maybe 4 qts. So is the book wrong on the amount or the dipstick wrong?

There were 3 engines used during the 790's production life...all Yanmar engines, but different. Are you sure you have the engine for your model (goes by tractor serial number, BTW)?
If 4 qts fills the sump, then that's what you want to use. Suggest you mark up your manual for future reference.
BTW, it's better to be a bit low (but still between the FULL/ADD marks) then too much oil.
 
   / Engine oil capacity of JD790? #6  
Should've read your profile before replying to your post. You are no newbie with tractors or engines. :eek:
 
   / Engine oil capacity of JD790?
  • Thread Starter
#7  
There were 3 engines used during the 790's production life...all Yanmar engines, but different. Are you sure you have the engine for your model (goes by tractor serial number, BTW)?
If 4 qts fills the sump, then that's what you want to use. Suggest you mark up your manual for future reference.
BTW, it's better to be a bit low (but still between the FULL/ADD marks) then too much oil.

My sn is LV0790G69xxx and I show it as a 2003 from the sn range.
I bought this used from original owner, it only had 95 hours on it and is a cream puff.
I always try to get the oil right on the "full" line and it's OVER by maybe half the distance between full and add.
Never thought about it but suppose there are there different dippsticks?
 
   / Engine oil capacity of JD790? #8  
My sn is LV0790G69xxx and I show it as a 2003 from the sn range.
I bought this used from original owner, it only had 95 hours on it and is a cream puff.
I always try to get the oil right on the "full" line and it's OVER by maybe half the distance between full and add.
Never thought about it but suppose there are there different dippsticks?

I believe there were different dipsticks as well as different locations.
My 790 (when I had one) was also a 2003 build. The dipstick was definitely a PITA to get to!
 
   / Engine oil capacity of JD790?
  • Thread Starter
#9  
I believe there were different dipsticks as well as different locations.
My 790 (when I had one) was also a 2003 build. The dipstick was definitely a PITA to get to!

Roy--you are spot on. I just looked up the parts at Deere and there are three different configurations, three different blocks and three different dipsticks. Me included for not even thinking of different blocks.
It's raining cats and dogs but when it's done I'll head out and find my PITA dipstick and try to figure out what I have. Not sure yet but I might not have the right dipstick but don't hold it to me just yet.
 
   / Engine oil capacity of JD790?
  • Thread Starter
#10  
OK, I checked the serial number and confirmed I have the correct dipstick. So, here's a photo of what appears to be the correct dipstick with the oil showing how much over it is. Since the 790 only holds a little over 4 quarts I figure this is OK even though I know not to "overfill", even though I am not sure I am actually overfilling.

Reason for this is I have had and seen other Deere tractors with small Yanmar engines that were damaged by low oil. I saw a Deere 950HC that had low oil pressure and when we went through the diagnoses learned that the Yanmar engine in it had an oil flow system that would starve the main bearings first in an issue of low oil. Since onlyy 4 qts are in the thing, one quart low would to be an issue. And since the oil is is hard to check, guys don't do is so often

So I maybe I have what appears to be too much oil and maybe I don't. But snce the engine is a blueprinted mechanical manufactured item it would appear the correct amount of oil is as stated and correct. For whatever reason, the dipstick is reading wrong?
Any thoughts on this?
 

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