So I did a thing... Agria 8900D

[groundcover]

Worth dropping a new engine into it ?

 

[ptsg]

Hopefully that's the extent of it.

Me too!

Since Piston hit the head and valve are you sure the crank or connecting rod are not damaged. Like you stated a whole lot of inertia to shear that flywheel key and drive that valve stem through the head, break piston skirt, etc.

There lots of signs of fretting happening between the crankshaft and the flywheel, so I suspect at one point, it ran slightly loose. That could cause most of the damage on the key.

The connecting rod is massive for the size of the engine and an initial assessment didn't looked like it was bent. Crankshaft is fine.

Worth dropping a new engine into it ?

Lombardini (part of Kohler) still produces this engine today. A new one is nearly €4,600, about what the tractor is worth when it's all fixed and in running condition. An used one is no where to be found, not even one for parts so I could snag the head.

 

[oldnslo]

Pt
Wishing you the best on getting than tractor operational again.

 

[ptsg]

Pt
Wishing you the best on getting than tractor operational again.

Thank you oldnslo! I'll need it!

I did left the head at the engine repair shop today. Interestingly enough, the guy was more worried about the hole that the valve stem poked through the head than the damage on the valve seats. He says he can handle the seats no problem.

 

[MTGreen]

Thank you oldnslo! I'll need it!

I did left the head at the engine repair shop today. Interestingly enough, the guy was more worried about the hole that the valve stem poked through the head than the damage on the valve seats. He says he can handle the seats no problem.

Is he going to Magnaflux the head to look for cracks?
I'm thinking that's a possibility with the piston hitting the head -especially considering the fractures on the piston skirt

 

[ptsg]

Is he going to Magnaflux the head to look for cracks?
I'm thinking that's a possibility with the piston hitting the head -especially considering the fractures on the piston skirt

We didn't go that far yet. Basically he was still going to see if he could fix the head. Maybe he will give me an update later in the week.

 

[ptsg]

Still no news on the head but I have been doing some more work on the tractor. Took the start apart, gave it a good cleaning and lubricated what needed lubrication and it's good to go.

Also machined a new woodruff key, technically two since I made it out of round stock. Might as well get a spare.

Had to modify the oil filter housing, because evidently they changed filter sizes between when my engine was made and now, even though this is a OEM filter. This required make an aluminium insert so the seal has a place to seal. Also, the original thread was M16x1.5 while the new one is M14x1.5. This required me to machine an new threaded insert with both threads. Of course, I could've just bought the oil filter + filter housing kit, but at this point, I'm sure you already know how cheap I am.

The air filter box also needed some work. Somehow got some rust holes on the top of the housing which is kinda weird to me. Also got a crack on the size because the hood had been hitting it for who knows how long. All fixed now, just need paint.

There was an adapter fitting between the injector line and the injector. Someone cross threaded it before, so it was a pain to remove and essentially broke the fitting in half. Had to remove the broken bit from the line by welding a washer and then a nut. Luckily it came out that way. Couldn't source a new one anyway, so I just machined one.

Today I spent some time pulling the seat out, so I could remove the top cover of the rear transmission of the tractor. I was eager to see the condition of it and why the main shifter (1st to 4th) was stuck. Turns out the shift rails were rusted and I suspect the detent springs are probably gone or very very rusty and weak. A little bit of WD-40 took care of the stuck rails. I will pull everything apart to clean it really good.

I knew there had been some water in it and it became very obvious that there would be some rust involved. On the bright side, I inspected all the gears, and everything looks nice, just a little bit of wear which is to be expected. I forgot to take pictures after I removed part of the diff lock mechanism, the rectangular plate with the shaft poking through. I would have made it easier to see the diff.

 

[MTGreen]

Nice work!
On the oil filter adapter insert it appears from the pic that you machined a smaller diameter thin ring that press fit on the OD to the ID of the cast ring boss. There is an overhang of the insert over the cast oil passages. I'm trying to understand how that is going to seal correctly and not have a seeping leak, especially when there's a possibility of that thin ring flexing from over tightening the filter with that overhang? Did you use a boring head or rotary table to cut a flat base on the casting to create a flat surface for that insert to seat up against?

Here is an idea using an o-ring to make an adapter that avoids that potential issue. It would space the filter out a bit and may or may not require a longer threaded insert depending on thicknesses involved. This style adapter would also avoid any overhang obstruction of those oil passages although it's likely not that significant. Here is a sketched cross-section of what I have in mind:

 

[ptsg]

Nice work!
On the oil filter adapter insert it appears from the pic that you machined a smaller diameter thin ring that press fit on the OD to the ID of the cast ring boss. There is an overhang of the insert over the cast oil passages. I'm trying to understand how that is going to seal correctly and not have a seeping leak, especially when there's a possibility of that thin ring flexing from over tightening the filter with that overhang? Did you use a boring head or rotary table to cut a flat base on the casting to create a flat surface for that insert to seat up against?

Here is an idea using an o-ring to make an adapter that avoids that potential issue. It would space the filter out a bit and may or may not require a longer threaded insert depending on thicknesses involved. This style adapter would also avoid any overhang obstruction of those oil passages although it's likely not that significant. Here is a sketched cross-section of what I have in mind:

Thank for the ideas and the sketch. All valid concerns indeed.

I only had about 3 to 3.5 mm (about 1/8") of thickness to work with. The o-ring idea is great, but didn't have much room to work with. I could also have cut the o-ring groove on the filter housing instead of on the ring.

I machined a mandrel with the M16x1.5 thread and did it so it would stick about 2" from the chuck and threaded the filter housing on it. This allowed be to use a boring bar to machine the inner diameter of the factory sealing ring to true up all the surfaces.

Then I machined the new ring, to press fit on the filter housing. On this ring, I machined a tiny groove on the outside diameter, just with the tip of the toolbit, then used Loctite 603 and pressed it into place. This idea was that it would provide a groove for the glue to sit and hopefully provide a good seal all around it.

Finally, I put the mandrel back on the lathe, and machined both surfaces flat. Also, on the ring, I machined a taper inside so it would give more clearance on that hole in the filter housing. Not entirely necessary but just an extra step to make sure. The angle of the photo above doesn't help and makes it look like it covers a lot of the hole but it really doesn't.

I think it will work fine but won't be surprised if it tries to leak on me.

One issue I didn't realize before is that the OD of the new filter bottoms out on the original sealing surface. While the seal of the filter sits proud about 2 to 3 mm, I'm a little concerned it may try to leak there. I may sill go ahead and turn the outside diameter of the original sealing surface down a little bit.

I hope I explained this in an understandable way.

 

[MTGreen]

Thank for the ideas and the sketch. All valid concerns indeed.

I only had about 3 to 3.5 mm (about 1/8") of thickness to work with. The o-ring idea is great, but didn't have much room to work with. I could also have cut the o-ring groove on the filter housing instead of on the ring.

I machined a mandrel with the M16x1.5 thread and did it so it would stick about 2" from the chuck and threaded the filter housing on it. This allowed be to use a boring bar to machine the inner diameter of the factory sealing ring to true up all the surfaces.

Then I machined the new ring, to press fit on the filter housing. On this ring, I machined a tiny groove on the outside diameter, just with the tip of the toolbit, then used Loctite 603 and pressed it into place. This idea was that it would provide a groove for the glue to sit and hopefully provide a good seal all around it.

Finally, I put the mandrel back on the lathe, and machined both surfaces flat. Also, on the ring, I machined a taper inside so it would give more clearance on that hole in the filter housing. Not entirely necessary but just an extra step to make sure. The angle of the photo above doesn't help and makes it look like it covers a lot of the hole but it really doesn't.

I think it will work fine but won't be surprised if it tries to leak on me.

One issue I didn't realize before is that the OD of the new filter bottoms out on the original sealing surface. While the seal of the filter sits proud about 2 to 3 mm, I'm a little concerned it may try to leak there. I may sill go ahead and turn the outside diameter of the original sealing surface down a little bit.

I hope I explained this in an understandable way.

Yes I think I follow. I like the groove idea to provide space for the locktite. What I wasn't clear on is if you machined a surface in the oil passage portion of the casting parallel to the filter seat for the insert to seat up against and provide for axial loading or if the insert is only being held suspended by the press fit OD?

Hopefully it will hold with the additional filter edge clearance cut as you mentioned. It occurred to me that if it does leak sometime down the line that groove for locktite could be replaced with a thin oring around the OD of the insert to allow for some flex.

Nice work and thanks much for sharing!