Green Tractor Talk banner

1 - 20 of 39 Posts

·
Registered
Joined
·
10 Posts
Discussion Starter #1 (Edited)
Got a couple questions on reassembling the engine on a 2025r from a novice. I'm mechanically minded but never been inside an engine before.

Quick back story is we have been using the tractor to mow at the office for ~4 years and the person mowing put it into the pond running nose first. Only the seat was sticking out when I went out there to wade in and pull it out by the lift arms. I honestly don't want to know really it's just better that way at times :banghead:. Tractor was under insurance still so had the local deere dealer pick it up and take a look and report back was a bent connecting rod, the engines can't be rebuilt so $13k. Once some parts were depreciated we would have to put out about $3000 for it and said no thanks just bring us back the parts; we'll get a zero turn and deal with the tractor ourselves.

Took the pistons down to our maintenance shop we use for the trucks and asked them to take a look (little smaller than the semi engines but we do a lot of work there and have a good relationship. Their opinion was they couldn't really find any bends/imperfections everything measured out exact that they could find. If there was anything it was very very minute. If it was theirs they would clean everything up really well and put it back together; see how it runs. Not looking to bash on anyone I get it; no one wants to put risk liability putting stuff together on an insurance job then it had an issue and breaks 3 months down the road due to something unforeseen. Instead it's if it could be wrong replace it.

Got a gasket kit and technical manual. Found I'm missing half of the bearings that go to the connecting rods already so I'll have to order 3 sets of them and a ring set (busted an oil ring putting them back on). Here's my questions:

1. The technical manual talks about making sure that every piston is marked to make sure that they go back into the cylinder they came out of. That's not going to happen unless there are marks I can't find. I got pistons and rods dissembled in a box along with (hopefully) all the bolts, ring clamps, etc that I'll need. Are the pistons marked somehow from the factory? I even tried looking for a wear pattern in common with the head and just can't make anything out.

2. I'm seeing torque specs from 20 to 200-243. I'm assume a pretty basic set of 3/8: 10-90# and then 1/2: 20-250# will take care of me? I see 1/4" wrenches that say 20-200 on them but really question getting that much torque accurately with the wrenches as short as they are.

Anything I really need to be aware of other than take my time, follow the manual and lots of lubriplate grease as it's going together?
 

·
Premium Member
Joined
·
423 Posts
Pistons should have been marked during disassembly at dealership. If not have the block honed and get new ring sets.
Your not building a high RPM race motor, so you should be ok.
The 1/4" torque wrench is inch pounds, not foot pounds.
 

·
Super Moderator
Joined
·
5,198 Posts
The pistons aren't marked by the factory. The same pistons are used in all cylinders and they are interchangeable when new.
 
  • Like
Reactions: PJR832

·
Registered
Joined
·
4,436 Posts
Pistons should have been marked during disassembly at dealership. If not have the block honed and get new ring sets.
Your not building a high RPM race motor, so you should be ok.
The 1/4" torque wrench is inch pounds, not foot pounds.

I'll second this. The 1/4" wrench is in inch-pounds, which is great for small engines and transmission work, but not for a diesel. the 3/8 and 1/2 should be fine, but I would get them calibrated before you use them.

I would get new rings and use a hone on the cylinders before re-assembly. Your local auto parts store may loan you one.

If the dealer lost the bearings, make them give you new ones. Don't buy them unless you need to. I would also make sure the injection pump doesn't have water in it, and make sure to use NEW head bolts and NEW injectors. There is a very experienced ex-navy diesel tech I watch that I picked that up from. He said its better to replace the injectors now rather than have a tip blow off and wreck a new build later.

and :ttiwwp:
 

·
Registered
Joined
·
1,864 Posts
I too agree with everything said.

The reason the manual wants you to mark them is because they are expecting you to put the same parts back in, and in that case, the rings are mated to each cylinder and its not a good idea to go swapping them cylinder to cylinder. Bearings too.
But since it sounds like you are doing new rings and bearings, no worries there.

Since you asked about the torque wrenches, Ill add this too.
Make DARN SURE you are reading the torque specs correctly before you go tightening anything. Foot Pounds, Inch Pounds, and Newtons are not the same thing. If you dont know what the manual is calling for, post a picture and ask. Better to do that than to have to have hardened bolts removed because they were snapped off.

Good luck with your rebuild! Wed all love to see pictures along the way!
 

·
Registered
Joined
·
10 Posts
Discussion Starter #6
Since you asked about the torque wrenches, Ill add this too.
Make DARN SURE you are reading the torque specs correctly before you go tightening anything. Foot Pounds, Inch Pounds, and Newtons are not the same thing. If you dont know what the manual is calling for, post a picture and ask. Better to do that than to have to have hardened bolts removed because they were snapped off.

Good luck with your rebuild! Wed all love to see pictures along the way!
Thank you very much for pointing that one out again. I probably should have picked it up off the comment earlier about the 1/4" torque wrench being in Inch lb earlier but some of my readings that I was thinking were foot# are actually Inch#. I would have screwed that one up without it being spelled out.

I was out of town when the dropped it back off; loaded up on a trailer and brought it home. Here's what I got to start with when I unloaded it off the trailer Saturday morning in my garage. The surface rust and staining came out of the cylinders pretty easy but it look (this is a before pic) but it looks like I'll be doing some more work to them anyhow.
 

Attachments

·
Registered
Joined
·
10 Posts
Discussion Starter #7
I would get new rings and use a hone on the cylinders before re-assembly. Your local auto parts store may loan you one.

If the dealer lost the bearings, make them give you new ones. Don't buy them unless you need to. I would also make sure the injection pump doesn't have water in it, and make sure to use NEW head bolts and NEW injectors. There is a very experienced ex-navy diesel tech I watch that I picked that up from. He said its better to replace the injectors now rather than have a tip blow off and wreck a new build later.
Question on the injectors. The tractor took a bath at 300 hrs on the nose. The existing ones should have a lot of life in them should they not? Or should I be concerned about any thermal shock to them from going into the water hot. I can spend $750 on injectors if it's a good idea but I'm not sure if the low hours on the motor changes that equation at all?
 

·
Super Moderator
Joined
·
8,139 Posts
Just caught up with this thread. Before you go any further with engine repair plans I have to ask if anyone has inspected the hydro for water contamination? If it was fully submerged it may have taken on some water through the vent. Best to check by draining it ASAP.
 

·
Premium Member
Joined
·
13,642 Posts
Question on the injectors. The tractor took a bath at 300 hrs on the nose. The existing ones should have a lot of life in them should they not? Or should I be concerned about any thermal shock to them from going into the water hot. I can spend $750 on injectors if it's a good idea but I'm not sure if the low hours on the motor changes that equation at all?
In general those injectors have a lot of life left in them, but in doing a complete engine rebuild it is simply not worth the risk to try and save a some money (in the overall picture) to try and reuse old injectors. I've been down that road with a truck engine, and sure enough, one injector tip after another, after the second one we replaced them all.
 

·
Registered
Joined
·
12,487 Posts
IDK for sure-but if it was me doing this project-i think i would want to get the block dipped and baked-start out with a good clean block then.
am i wrong in thinking like that?

are u gonna take the injector pump off-and have that gone over?

and like someone else stated -i would drain the oil of the hydraulics and rear end to see if water got in it. me thinks they seen more than meets the eye and that's why the bill was set at $13,000 to fix it. good luck with it.

if no water in rear of tractor -then good. but i would find out first before attempting the motor.

if no water in there-then go full steam ahead i guess.
 
  • Like
Reactions: johnH123 and PJR832

·
Registered
Joined
·
10 Posts
Discussion Starter #11
Just caught up with this thread. Before you go any further with engine repair plans I have to ask if anyone has inspected the hydro for water contamination? If it was fully submerged it may have taken on some water through the vent. Best to check by draining it ASAP.
I'll get it drained tonight and check it out. I would have thought it was a closed system, didn't realize there was a vent somewhere in it.
 

·
Registered
Joined
·
4,436 Posts
Question on the injectors. The tractor took a bath at 300 hrs on the nose. The existing ones should have a lot of life in them should they not? Or should I be concerned about any thermal shock to them from going into the water hot. I can spend $750 on injectors if it's a good idea but I'm not sure if the low hours on the motor changes that equation at all?

Replace them. Sooner or later a tip WILL blow and wreck the cylinder.
 

·
Registered
Joined
·
1,864 Posts
Question on the injectors. The tractor took a bath at 300 hrs on the nose. The existing ones should have a lot of life in them should they not? Or should I be concerned about any thermal shock to them from going into the water hot. I can spend $750 on injectors if it's a good idea but I'm not sure if the low hours on the motor changes that equation at all?
Not meant to ruffle any feathers, just pointing something out.
While I know some say replace, its generally based on a feeling more than anything. Take the one opinion here, its based on one other mechanics recommendation.
We all do things based on someones recommendation, but Id do a bit more research because theres more to it than a "tip" blowing off.

How are the injectors made for the Yanmars? How do they come apart? Some have no parts that separate on the front, they come apart only from the rear. Most use stainless components, so water submersion isnt really an issue with them.
Most injectors have only the nozzle itself anywhere near the cylinder. The nozzle being changed out is what is generally meant by "bigger injectors" with regard to diesels. My VW is running bigger "injectors". Its actually just larger nozzles. The injectors themselves have 335,000 miles on them.


The point of all of that is this. Find a local or semi local diesel performance shop and have them go through your injectors. Its MUCH cheaper than buying new, and they will work like new when done.
Its your money, not ours, and sometimes we are much more free with other peoples money than with our own.
 
  • Like
Reactions: BigJim55 and Kennyd

·
Administrator
Joined
·
18,291 Posts
I'll get it drained tonight and check it out. I would have thought it was a closed system, didn't realize there was a vent somewhere in it.

There has to be vent or the case/tank would get pressurized as the fluid expands when hot. I "think" it's #9 in the pic below:


0002185833____________A1.jpg
 

·
Registered
Joined
·
10 Posts
Discussion Starter #15
Sorry one more question before I get too far also. I know that there are 2 generations so to speak for the 2025r. Mine's a 2013 model year SN ends in DH110184. I specified that when I ordered the tech manual and was told that this is the correct one. I found one minor thing that didn't match up to a diagram but it wasn't a huge deal. I just want to make sure that I'm not setting myself up for failure later on. The tech manual shows SN HH100001 -.
 

·
Registered
Joined
·
2,073 Posts
When they go for a swim while the engine is running, water is drawn through the air cleaner, intake path and into a cylinder. A fluid does not compress, like air, so when the not so lucky cylinder whose piston was coming up on a compression stroke encountered the water it couldn't compress. It stopped--suddenly. This sudden stoppage usually bends/breaks something or multiple things. My first suspect would have been a connecting rod, as well. I've never been that far into one of these engines, but my next area of concern would be crank twist.
 
  • Like
Reactions: BigJim55 and PJR832

·
Registered
Joined
·
2,073 Posts
Also, electronic circuit boards and water do not co-habitat together well. At this point you're probably going to be looking at replacement of the instrument cluster and anything else with a circuit board.

I operated a Motorola two-way sales/service dealership for 30+ years in an area with many lakes. It was a pretty common occurrence for an on-call firefighter to either fall in a lake with his pager on or drop it in the lake somehow. If they got them to us within 24 hours, we could pull them apart, thoroughly spray the boards with component cleaner to displace water, let them dry out overnight, put them back together the next day and they were fine. However, if that didn't happen within that 24 hour period, the corrosion would begin to set in. We learned the hard way not to attempt repairs on them after that. We could troubleshoot, identify the defective component, replace it, and return it to the customer. A week late they would be back, as something else let go from the corrosion. They expected and we did repair it again as part of our repair warranty. This went on for about six weeks, and we hand racked up twice what is worth in repair hours, about $800. I finally cut my losses and gave them a new replacement pager.

The best lessons in life are those you pay dearly for.

We had a particular fire chief that owned a bait store and launch service. His son-in-law and employees were also firefighters. So we had them trained pretty well to get the pagers into us right away when they went for a swim. I still chuckle about this as I'm typing this, but once they brought one into us in a clear plastic bait bag, full of water. Their logic was to prevent the air from getting to it, not that it really made a difference with the other minerals in the water. One of my techs looked at them when they brought it in, and with a straight/serious face, inquired if they had put oxygen tablets in the water as well?
 

·
Registered
Joined
·
193 Posts
Injectors can be tested, rebuilt, or replaced. You already have the engine and injectors disassembled, go ahead and have the injectors tested.

Be sure you get the water out of all compartments of the tractor, you can flush with clean oil, diesel, or something like berryman's b-12.

At a minimum, I would replace the connecting rods, rod bearings, and have the crank checked/blueprinted/straightened. A local speed shop can do this for you. The crank may be fine, but I would bet the one or more rods are bent and the bearings got stepped on pretty hard as well.

You might consider looking for a burned machine or a salvage machine that has a complete undamaged rotating assembly, and reuse the rest of your parts. I would look for parts machines in the north end of the US, stay away from the south because of all the hurricane damaged equipment.

Take your time and flush the machine of water, then worry about parts, the longer you wait, the better you will do economically. Parts will come along.
 

·
Registered
Joined
·
193 Posts
This is a Yanmar 3TNV80 engine correct? Same as a 1025R. I found 2 running take out engines complete on ebay. Consider buying a pullout engine and doing a swap. After you get a good runner, sell the leftover parts online to recoup some of your costs.

Also, you don't have to buy new parts from Deere such as the connecting rods. Find a Yanmar dealer, and get your engine model, serial number, and arrangement off of the top of your valve cover.

Yanmar engines are used in military generators, boats, water pumps, and other stationary powered items. Take a look around and you may find a complete new engine military surplus, just as we do with our military trucks.
 

·
Registered
Joined
·
715 Posts
Question on the injectors. The tractor took a bath at 300 hrs on the nose. The existing ones should have a lot of life in them should they not? Or should I be concerned about any thermal shock to them from going into the water hot. I can spend $750 on injectors if it's a good idea but I'm not sure if the low hours on the motor changes that equation at all?
Injector problems almost always originate from the fuel supply end and not the nozzle. Crap gets past the fuel filters (this is one reason why regular maintenance is necessary) and clogs the injector from the inside. If the engine suffered damage to the combustion chambers, e.g. someone filled the tank with petrol instead of diesel, then you can rightly suspect damage to the injector nozzles. Otherwise, I would see what happens when you reassemble and start the engine and replace them then if there is a problem.

Al
 
1 - 20 of 39 Posts
Top