So I did a thing... Agria 8900D

[ptsg]

A couple days ago, I was scrolling through Marketplace, mostly looking for lathe and milling machine tooling, until an ad for a cheap articulated tractor with a tiller popped up. That instantly got my interest, it was cheap and somewhat close by (only 1 hour and bit away).

While I wasn't actively looking for a tractor, I've been toying with the idea of getting a smaller and cheap tractor just to till the orchards at home, so I don't have to haul my bigger one back and forth between proprieties (about 50 miles apart) as fuel only gets more and more expensive.

Anyway, went there and looked at it. Seller said he bought it in a lot with some other stuff. All he knew was that it hadn't run in a long time and had a guy before looking at it before me that said it had a broken connecting rod. So I turned the engine by hand, 0 compression, only rotated like 270 degrees till it hit something inside. The center section, both steering and left/right tilt had a lot of play, some minor stuff missing, fairly decent tires for the use it'll have, along with some other stuff wrong.

So I did the next logical thing and bought it regardless. It also came with the original 2 point mounted tiller.

It's an Spanish made Agria 8900D, about 1970-ish would be my best guess. Here are some specs of it:

- Engine: Lombardini 4LD820 - 21HP 1 cylinder air cooled diesel engine with 817cc.
- Transmission: 8x4 - High/Low and Reverse with the same lever (almost like a shuttle) and 4 main gears. 4WD engaged with a lever (most equal wheel tractors can't disengage the front axle)
- PTO: 1 PTO output shaft with 2 speeds (540/750) + another one with 2 speeds as well but synchronized with the ground speed used with PTO driven trailers
- Steering: Articulated with a worm drive steering box, also no stops so it can go literally till the tires touch
- Brakes: Drum brakes on both axles. Brake pedal actuates the rear brakes and hand brake actuates front brakes.
- Hitch: Hydraulic 3 pt hitch
- Height: 38"
- Width: 32" to 39"
- Length: 95"
- Wheelbase: 44"
- Weight: 2000 lbs
- Tires: 7.5 x 16
- Front and Rear Diff locks

Some of these specs makes it a very nice tractor to work on orchards and hills. After all, it was made for it. A great reason why this one really got me interested.

After a quick assessment at home, here are the some of the main issues with it. More issue will arise as I dig further into it.

- What was a broken connecting rod translated into dropped exhaust valve instead, so hard it poked it through the head
- Various leaks on the engine
- Was run without a clutch pedal return spring so it destroyed the throw out bearing and put a lot of wear on the pressure plate fingers
- Missing the 3 pt lower arms and side links. Easy to make even though this will probably have the tiller attached most of the time
- Broken fender mounts
- Bent levers and linkages
- Messy electric system
- Various cosmetic stuff here and there
- A lot of play in the center section where steering pivots and where the front half pivots in the relation to the back half (like the front axle pivot on a conventional tractor).
- Surprisingly, only leaks a little bit out of the 3 pt valve and maybe one of the wheel seals
- Needs new seat
- Both U joint shafts have play
- Broken alternator mount

This will be a very budget oriented restoration. Mostly to fix stuff enough to get it running again, then with time, fix whatever it needs properly. Main focus is engine right now.

That's all for now. More to come as I dig into it further more.

 

[ptsg]

Some more pictures so it doesn't fill the previous post:

 

[ericm979]

- Steering: Articulated with a worm drive steering box, also no stops so it can go literally till the tires touch

Seems like that'd make it come to an instant stop.

Sounds like a good project with your skills.

 

[MTGreen]

Wow looks like quite a project!
Neat tractor though.
Looks like it needs some quality time getting acquainted with a pressure washer before one can admire the "patina".
Good luck!

 

[ptsg]

Seems like that'd make it come to an instant stop.

Sounds like a good project with your skills.

This thing turns to tight that I think when in use, one doesn't even need to turn all the way. Regardless, I think I already have a plan to add some steering stops.

Wow looks like quite a project!
Neat tractor though.
Looks like it needs some quality time getting acquainted with a pressure washer before one can admire the "patina".
Good luck!

Thank you!

I did have a go at it with the pressure washer. Turns out, I lost the fight on most of the worse spots. So I'll be doing the hard (messy) way.

 

[MTGreen]

I did have a go at it with the pressure washer. Turns out, I lost the fight on most of the worse spots. So I'll be doing the hard (messy) way.

I had that problem until I got fed up and bought a 13hp 4+gpm 4k+ psi pressure washer and now the problem seems to have improved markedly. Issue now is I have to be careful not to blow water past seals

 

[2manyrocks]

Super interesting. I don't know why we don't have more of these kinds of tractors available in the USA?

 

[MTGreen]

Super interesting. I don't know why we don't have more of these kinds of tractors available in the USA?

I would hazard a guess that the simple answer is market and space. In the 1970s when the technology was available, the individual yeoman farmer of small plots of maybe marginal land that this type of tractor was designed for was largely out of date. Population density of the US was much lower than Europe and much of the world with much larger expanses of suitable ag land, so the ag market in the US was more geared towards higher production equipment for larger plots

 

[ptsg]

I started the process of pulling the engine out, to start taking it apart, however the curiosity got the best of me and went to pull the head instead.

Pulled the exhaust out and instantly could see the valve laying there in a weird position. After seeing the valve there, went and look at the top of the head and sure enough, there was the valve stem just poking right through the head. It even put a slight dent on the air duct cover.

Then it was time to pull all the shield and air ducts, air filter, alternator, hydraulic pump, etc. Had the mandatory mouse nest, pretty common on these neglected air cooled engines, along with everything just covered in a mess of oil, dirt and whatever.

It was finally time to pull the head out and what a sight it was.

A brand new head is around €1100, which more than the tractor is worth at the moment. The plan is to go to an engine shop and see if they're interesting on trying to repair this one. The hole through the top of the head doesn't concern me, I can handle that by turning a plug and put it there.

The bottom side of the head is what concerns me a little bit. I have no way to weld aluminium or any tooling to do a valve job, so that's definitely a job for the professionals, if they want to bother

Even though the valve came very close to the injector nozzle, to the point of deform the hole, I think the injector is fine. It also put just a slight bend on the push rod which should be easy to fix.

 

[ptsg]

With the head out of the way, I proceed to pull the rest of the engine out. The beauty of these tractors is that you can simply pull the engine out. No need to split the tractor and hold each section with jackstands.

At first glance, the piston only had a couple dings from hitting the valve, but after pulling the piston out, turned out it was cracked around the wrist pin.

So now I need a new piston as well. That's not too expensive and it comes with piston rings as well.

As I got further into the disassembly of the engine, I noticed the fuel delivery adjustment plate was pretty much maxed out. I don't know if that was the cause for the failure but most definitely didn't help any.

I'm pretty sure the engine got a new piston, rings and sleeve not too long before the failure, just based of the very little wear I found.

The rest of the engine was just fine. Main bearings, connecting rod, cam, etc, all in good shape.