Green Tractor Talk banner

1 - 20 of 28 Posts

·
Registered
Joined
·
455 Posts
Discussion Starter #1 (Edited)
My Z710A with the 23 HP Kohler didn't come with a oil cooler. Some of those Z700, Z800, and Z900 series Ztraks came with oil coolers.
So, this is a winter project for now, as I have decided to install a John Deere/Kohler oil cooler on my engine. Here is a picture of the oil cooler less the sandwich adapter. I have bought a different adapter for the cooler. I will not be connecting it to the top engine housing as the factory ones. Instead, I will form a bracket to install it some three inches on the right side of the engine bay with a 4' x 4" 12 volt fan to push the air into the cooler fins.
Now, the big 64 thousand dollar question. How much engine oil should I add to the crankcase? It appears to me the oil cooler probably will hold about 1/2 pint or less. With this extra oil in the crankcase and it will show more on the dipstick. The user manual doesn't state anything about this on engines that have the factory oil cooler installed.


 

·
Administrator
Joined
·
20,987 Posts
I wouldn't worry about the amount. Once it reaches full, you're done.

Personally I would add the cooler, change the oil and filter, add the usual back in, start the engine to fully circulate the oil and get an accurate level. Top off as needed. Done. :thumbup1gif:

If it drains down over time, meh, so what? When you start it back up, it'll fill everything back to where it should be. :good2:
 

·
Registered
Joined
·
455 Posts
Discussion Starter #3
I wouldn't worry about the amount. Once it reaches full, you're done.

Personally I would add the cooler, change the oil and filter, add the usual back in, start the engine to fully circulate the oil and get an accurate level. Top off as needed. Done. :thumbup1gif:

If it drains down over time, meh, so what? When you start it back up, it'll fill everything back to where it should be. :good2:


I agree with what you have said. However, the oil cooler takes the extra amount of oil with the engine running, meaning less oil in the crankcase. Did John Deere with the oil coolers have a different dipstick to show the extra oil? When I get it all installed I will add the extra oil and see what happens to the dipstick measurement.
 

·
Administrator
Joined
·
20,987 Posts
I agree with what you have said. However, the oil cooler takes the extra amount of oil with the engine running, meaning less oil in the crankcase. Did John Deere with the oil coolers have a different dipstick to show the extra oil? When I get it all installed I will add the extra oil and see what happens to the dipstick measurement.
That's why I said to check and top it off right after you shut it down. It won't drain down instantly. Trust me.
 

·
Chief Stick-picker-upper
Joined
·
11,834 Posts
I wouldn't worry about the amount. Once it reaches full, you're done.

Personally I would add the cooler, change the oil and filter, add the usual back in, start the engine to fully circulate the oil and get an accurate level. Top off as needed. Done. :thumbup1gif:

If it drains down over time, meh, so what? When you start it back up, it'll fill everything back to where it should be. :good2:
That's why I said to check and top it off right after you shut it down. It won't drain down instantly. Trust me.
I agree with Jason.

kbeaag, you may be overthinking the situation. :dunno: Oil checked COLD, at the full mark will be happy while running.
 

·
Registered
Joined
·
455 Posts
Discussion Starter #6 (Edited)
The factory John Deere/Kohler oil cooler is a 4" x 4" x 3/4" size, and my guess it is not large enough to really make a difference in cooling the oil.
I would like to install one about 6" x 6"x1" size and install a larger fan to cool the oil. In searching the Internet the majority of oil coolers are way too large...mostly above 11" x 11" size. Some transmission coolers are smaller, but, not that I can locate for the perfect fit to the tractor.
I'll keep searching.

Some may be thinking why install a oil cooler now. Well, here is my reason. I have a oil pressure gauge on the Z710A and during the hot summer days here, the temp near 100 degrees and mowing the heat of the engine is most important. My gauge usually registers at 46 psi, but, after several hours of mowing it get up to 55-60 psi on the gauge. That would cllick on ones mind that the oil is very hot and expanding...maybe boiling. Or it may signal something else triggers it to rise.






 

·
Old Pa-pa
Joined
·
11,985 Posts
The factory John Deere/Kohler oil cooler is a 4" x 4" x 3/4" size, and my guess it is not large enough to really make a difference in cooling the oil.
I would like to install one about 6" x 6"x1" size and install a larger fan to cool the oil. In searching the Internet the majority of oil coolers are way too large...mostly above 11" x 11" size. Some transmission coolers are smaller, but, not that I can locate for the perfect fit to the tractor.
I'll keep searching.

Some may be thinking why install a oil cooler now. Well, here is my reason. I have a oil pressure gauge on the Z710A and during the hot summer days here, the temp near 100 degrees and mowing the heat of the engine is most important. My gauge usually registers at 46 psi, but, after several hours of mowing it get up to 55-60 psi on the gauge. That would cllick on ones mind that the oil is very hot and expanding...maybe boiling. Or it may signal something else triggers it to rise.
Would think that the oil viscosity should decrease with increased temperature of running a couple of hours
causing the oil pressure to decrease some.
Oil flows more freely when less viscous decreasing pressure.
Notice this on my old Farmall Cub with the oil gauge mounted on the oil filter canister, will drop 5 lbs. or so once
at operating temp.

You seem to have the opposite happening.:dunno:
 

·
Administrator
Joined
·
20,987 Posts
I have a oil pressure gauge on the Z710A and during the hot summer days here, the temp near 100 degrees and mowing the heat of the engine is most important. My gauge usually registers at 46 psi, but, after several hours of mowing it get up to 55-60 psi on the gauge. That would cllick on ones mind that the oil is very hot and expanding...maybe boiling.
Your oil isn't boiling, I can guarantee that. It takes some extreme temps to do that. Pressure rising on an operating and hot engine? Doubtful. More than likely you have an indication issue. See below.

Would think that the oil viscosity should decrease with increased temperature of running a couple of hours
causing the oil pressure to decrease some.
Oil flows more freely when less viscous decreasing pressure.
Notice this on my old Farmall Cub with the oil gauge mounted on the oil filter canister, will drop 5 lbs. or so once
at operating temp.

You seem to have the opposite happening.:dunno:
OC is 100% correct. :thumbup1gif: Rising temps equals lower viscosity equals lower pressure.

I've never seen oil pressure rise on a hotter engine than when cold. Unless you have an exotic oiling system or a variable oil pump like some cars do. I doubt your oil cooled engine has that technology.

Again, my guess is you have an indication issue. Can you verify with a mechanical gauge?

Adding an oil cooler won't hurt your engine, only help prolong the oil's life and therefore your engine. It's a great addition to any engine, especially an air cooled one as they tend to run hotter than liquid cooled ones.
 

·
Registered
Joined
·
455 Posts
Discussion Starter #9
I'm not too concerned about the higher PSI on the oil pressure, as I'm safe to say it's better than having it to drop during the engine operations. When I first encountered this, I removed the gauge and sensor and returned them to the seller, so sent me a replacement. That didn't change anything...same results on PSI. So, I switch to another oil sensor I had here. No change. These Faris gauges are very reliable. So I discount they are the culprit on the higher PSI reading.

When I get the oil cooler install, will see if anything changes.
 

·
Registered
Joined
·
3,228 Posts
If you are running a multi grade oil like 10W30. It's designed to thicken up from engine heat. Transforming from a 10 to a 30 weight thickness.
 

·
Chief Stick-picker-upper
Joined
·
11,834 Posts
My Z710A with the 23 HP Kohler didn't come with a oil cooler. Some of those Z700, Z800, and Z900 series Ztraks came with oil coolers.
kdeaag, I'm trying to understand what the reasoning is for the addition of an oil cooler on this model. This wasn't stated in the original post.

I'm feel fairly certain tests were done and the outcome didn't require additional oil cooling. :unknown: Just asking.
 

·
Senior GTT Super Slacker
Joined
·
38,152 Posts
kdeaag, I'm trying to understand what the reasoning is for the addition of an oil cooler on this model. This wasn't stated in the original post.

I'm feel fairly certain tests were done and the outcome didn't require additional oil cooling. :unknown: Just asking.
X2 :munch:
 

·
Registered
Joined
·
455 Posts
Discussion Starter #14
kdeaag, I'm trying to understand what the reasoning is for the addition of an oil cooler on this model. This wasn't stated in the original post.

I'm feel fairly certain tests were done and the outcome didn't require additional oil cooling. :unknown: Just asking.
That is a very good question. And I have wondered why some had oil coolers and some didn't.

I find that this Z710A model with a Kawasaki 23 HP engine had oil coolers installed. Also, it shows that "some" Kohlers ..same HP had oil coolers. It may be that John Deere didn't setup oil coolers on tractors with 54" or 48" decks... only on the 60" and larger.
Anyway, I'm concerned about the heat that these engines get up here in the Midwest during the hot summer seasons.
 

·
Registered
Joined
·
455 Posts
Discussion Starter #15
This may be a stupid question to ask, but, how many of you owners here with Zero Turn mowers with the large HP engine have oil coolers? If you have a "air cooled" ZTR with a oil cooler installed, than you must not questioned why I would want one.
The engine had the adapter (for a cooler) where the oil filter screws into, and the ports for the hoses where blocked, but the blower housing didn't have the "cut-out" for one.

When I bought the Z710A with the Kohler 23 HP engine, and it didn't have a oil pressure gauge or a "idiot" light for that purpose. I installed the gauge and a sensor into one of the blocked ports on the adapter. That is where it stands now.
 

·
Chief Stick-picker-upper
Joined
·
11,834 Posts
My Z445 is equipped with a Kawasaki 25HP. It has a cooler attached to the engine block by adapter(#19).
I honestly didn't remember it having an oil cooler until I looked for it this morning. I guess it's because of the way it's mounted(no external hoses).

MP37212________UN10NOV05.gif

Hey, if it makes you feel more secure knowing an oil cooler it installed on your engine, go for it. :thumbup1gif:
 

·
Registered
Joined
·
455 Posts
Discussion Starter #17
My Z445 is equipped with a Kawasaki 25HP. It has a cooler attached to the engine block by adapter(#19).
I honestly didn't remember it having an oil cooler until I looked for it this morning. I guess it's because of the way it's mounted(no external hoses).

View attachment 511433

Hey, if it makes you feel more secure knowing an oil cooler it installed on your engine, go for it. :thumbup1gif:

I live a few miles...down the road a piece where Kawasaki Plant is in Marysville, Mo. I've been there several times when they have tours that you can see how they make those Kaws engines. I know they (Kawasaki) installs oil coolers on their larger HP engines...like the one you have and another way like those in the picture in my first posting.
I really don't see how these "attached" coolers really benefit ....the cooling process. I prefer the cooler to be some distance with a fan that really get the cooling done. That is my idea wanting a larger one with a fan located some inches from the engine.
 

·
Chief Stick-picker-upper
Joined
·
11,834 Posts
Apparently it's doing a good job at cooling the oil. I give this mower hell..... I mow as fast as it is able to travel, as long as I don't get bounced out of the seat. I change the oil on an unscheduled, schedule. The oil is changed once a year, whether it's needed or not. :laugh: I use whatever type, brand, weight oil I can get my hands on. The cheaper, the better. :good2:If the oil is free, I throw a party to celibrate. :laugh:
 

·
Administrator
Joined
·
20,987 Posts
Multi-weight oil doesn’t operate in a linear fashion. 10w30 operates like this. At cold temps, it acts like a 10 weight oil, at operating temps, it acts like a 30 weight oil. That doesn’t mean it’s thicker or more viscous. It just means it’s thicker at operating temps than a 10 weight. 30 weight when hot will easily outflow 10 weight when cold. Each weight has a linear range of viscosity vs temp. As they get hotter, the thinner they get. The difference is a 10w30 stays as thick as 30 at operating temp not as even runnier 10 weight would be at the same temp.

Does that make sense?

The multi-weight system means the viscosity grades are on a curve of sorts. They will all get thinner as the oil gets hotter. Some just don’t thin as much as others. That’s what that really means.


Back to the Z. I’ve thought about this. It could be the relief valve is lifting at colder oil temps allowing the pressure to fall to what you see. Once up to operating temps, it fully closes and allows a bit more pressure. You could be right at that magical setting for your relief valve to be lifting. Either way, a bit more oil pressure at operating temps is not a bad thing. I’d smile and keep on mowing. :drinks:
 

·
Registered
Joined
·
3,228 Posts
A lot of oil filters have a bypass valve.
 
  • Like
Reactions: raco232
1 - 20 of 28 Posts
Top