Tractor Repair


For Tractor repair, always refer to the service manual. We have a large number of service manuals on the resource page for free download. We encourage you to download the manual on to your computer by clicking on the link with the RIGHT mouse button and choosing "Save As" from the menu that comes up. If not familiar with the computer, get someone to help you so you can find it again (save to the desktop or a known directory).


Read the opening general information on the engine repair page as it also is applicable here.


Advice you may not find in the manual



Clutch replacement


Clutch replacement is a common concern so we dedicated the above link to clutches:


Cast iron housings


Many major castings like transmission cases, axle towers, rear differential housings, etc.

are no longer in production and out of stock, which means unless we can find a used one

for you, you are out of luck. Never try to draw two castings together using bolts. If it isn't

slipping together to the mating surfaces, there is something wrong. Trying to force castings

together using the fasteners will break a flange or destroy something else. Always fit them

together first. If they don't match up, a shaft, bearing, bushing or whatever is out of place

and preventing it from closing. Do not force it.


If you break a casting, they can often be repaired by an expert welder or mill wright. We

favor brazing over welding for cast. The entire casting needs to be heated up first. This

can be done with a propane "rose bud". Heat evenly, checking with a hand held laser temp

gun. After repair, keep the entire casting evenly heated, lowering the temperature as evenly

as possible until you are down to about 100 F. Here is an example using a "denture". More examples in the Gallery section.









  


Transmissions - Use 80/90 W (GL-5) oil in older gear boxes, GL-4 in newer syncromesh transmissions


If changing transmission fluid and you see silver sparkles everywhere, don't panic. Unless large chips are coming out, you are probably okay.


The Italians love needle bearings and snap rings. To work on their transmissions, you need a great (not good, but great) set of snap ring pliers. I use the heavy duty PROTO set number 361. These are ratchet pliers that help when working the large rings. I am sure there are others that would work well, it's just that I find the ratchet handles really help. I also have additional sets that are smaller to fit into tight places.

















Needle bearings are used everywhere in Italian transmissions. These bearings work beautifully, but should always be replaced if overhauling the transmission. Many deep groove ball bearings and rollers will last and last, but don't rely on older needle bearings. If your transmission starts to rumble and make noise, it's probably worn needle bearings. Regardless, all bearings need to be evaluated and replaced if suspect.


If your transmission has a level plug on the side as well as a fill cap, consider replacing the level plug with a sight glass. We have them in stock and they make a lot of sense. A quick glance and you can easily see the transmission oil level.


Replace drain plugs if they are becoming unserviceable, we have lots in stock.


The forward tips of the sliding gears get a bit rounded and banged up, don't let it worry you. They only need replacement when seriously chipped, broken or worn out.


All transmissions calling for SAE 90 transmission fluid (most of them) will benefit from 10-20% Lucas oil stabilizer. Available at Wal-mart or any automobile parts store. The product will extend the life of the transmission. Lucas oil stabilizer is not hype, it really works and is recommended.

Always ensure oil holes on all gears are clean of sludge before reassembly. You will find them everywhere in Italian transmissions. Early Pasquali transmissions have a fragile rear bearing casting for the center shaft. Ensure the shaft or bearing is not tweaked during replacement or renewal. Cases need to slide together completely before tightening bolts. You cannot "draw" a case together with bolts, it will break.Once the transmission cover is on, check the end play of the main shaft (pinion). The angular contact bearing should support it well. If you can move it side to side, check the end play of the shaft. It should be about .002 (two thousands of an inch) end play. If quite a bit more, remove the cover and add a shim behind the bearing for .002 or .003 end play. It is not uncommon to find .015 to .020 end play which is too much.


Ring Gear and Pinion


If the ring (or crown) gear and pinion have trouble, it's fairly serious. Ring and pinion gears are normally changed out as a set, but because of cost it is not unusual to try and save one if still in good shape. Regardless, setup of the ring and pinion is critical for optimum wear. The pinion is normally adjustable with shims both forward and aft, the ring gear side to side. Unless both are positioned correctly, uneven wear will result. Setup is achieved using colored grease, paint or Prussian blue paste until it results in the ideal tracking pattern when turned. There is enough information on the Internet how to do this, that it hardly makes sense to duplicate it. A few suggestions though:


1) Create some drag on the system when turning

2) Take your time and check both contact and coast

3) Replace both pieces if gear wear is observed

4) Some tractors like the older Pasquali used shims on the axle tower

    to adjust the back lash.


Don't be intimidated by differential replacement. It is a straight forward

process, it simply takes time. Refer to YouTube for adjustment.


Note: The crown and pinion pictured are from the disassembly pictures

of the broken case above. This is from a Goldoni Base 20 tractor.



Satellite Gears


Inside the ring (or crown) hub, there are two sets of satellite gears. These often break when operating the tractor with the differential lock on and attempting to turn. It is much worse on dry pavement as loose gravel or dirt may allow for some wheel slip. You often hear a cracking noise, snapping or popping while moving forward. These are easily replaced but normally create enough damage to warrant replacing as a complete set. We have full sets in stock for Pasquali's and can order Ferrari or Goldoni as needed.


Axles


Axles are pretty robust in Italian tractors, but I do know of several customers who have either broken them or stripped out the splines. What seems to take out axles is ballasted tires. Italian tractors have a lot of torque to the axles and dumping the clutch with ballasted tires takes a toll on axles. All of the early Pasquali tractors (991, 993, 988, 997) used the same axles except for the 986. We carry both in stock. The early Goldoni Universals also shared axle types, but Ferrari tractors are pretty specific.


Pasquali welds in the studs and unfortunately it necessitates pulling the axle to replace them. Grind the weld off and drive them out pounding the threaded side. Torque the wheel nuts at 25 lbs and you will avoid breaking them.


Mechanical Tachometers


The mechanical tachometers are always a problem on the early Italian tractors. Almost every early tractor with a Mechanical tach has about 500 hours on the clock. This has little to do with actual hours and a lot to do with the life span of old tachometer cables. It seems that about every 500 hours, the cable would fail and because of expense of replacing it, all tractors seem to have about 500 hours of use.


In most cases, it's the cable that's at fault and simply replacing the cable will solve the problem. You need to however ensure it's not the engine sending unit, a mechanical device that is either unavailable (Ruggerini, Slanzi) or if it is available, it's going to cost some major money to replace it.


To troubleshoot a mechanical tachometer (that is not registering), check the following:


1) Remove the cable by unscrewing both ends and pull the inner cable out of the outer sheath. If the cable is intact, it is the sending unit or the tach at fault.


2) Start the engine and look at the sending unit with a flash light. If the inner square drive socket is revolving, you may have a failed tach, but there is one more test you will want to try with the sending unit. Stop the engine and using a nail, square the end on a grinder so that it just fits into the square socket. Start the engine again and try holding the nail with your two fingers. If you can stop the center socket from revolving by putting pressure on the nail with your fingers, the inner gears are stripped. Lombardini sending units are still available, but expensive ($150 to $200). The older Ruggerini and Slanzi units are a thing of the past. If both cable and sending unit are working, go on to step 3.


3) Older tachometers are mechanical like early watches and while they can be repaired, parts are no longer available unless you have a collection of old tachs. You can test your tach with a toothpick or your squared nail. Place it into the rear socket and looking at the tach face, give the nail a number of fast clockwise twists. If the needle jumps and registers, your tach is still good.


When a mechanical tach has failed, you might be able to convert to a electronic tach depending on your tractor. Electronic tachs count pulses from the alternator and register the number of pulses as RPM. The problem is that early front pulley alternators are a bit of an unknown as to how they pulse. If there is a electronics guy out there that can explain how to read these, it would be extremely helpful. On the newer style alternators you can often find a terminal to hook up to and you check the rpm to a laser tach. By adjusting to the pulses, you have a replacement.


Note in this example the rear of the tachometer has a calibration adjust. This will

allow for testing to a simple laser tach. Laser tachs are well worth having for testing

purposes and are commonly available for about $20. You place a reflective strip

of tape on the front pulley and pointing the laser tach at it, it will count the number

of revolutions the crankshaft is turning. This should match the tach reading. If it

doesn't you can try calibrating it. Also note on this example there is a A,B,C,D,E

that can be chosen. This allows you to match the Hz of the alternator, like 250,

345, 500, 750 or 1200. Other alternators might be specific to one Hz setting and

may or may not work correctly.


Unfortunately, I am not an electronics guy and don't have the answer here. I just

know that it has been done. I have heard of people tapping into the stator to read

AC pulses and having them accurately reflect RPM on a tach.


There is also a product called "Tiny Tach". These are quite ingenious little devices,

​using a transducer that fits over one of the fuel injection pump lines. This counts the

number of injection pulses and calculates the number of revolutions per minute based

on the injection cycle. It comes with a digital readout and also an hour meter reading. While it doesn't look like a stock tachometer, it gives the necessary information economically and efficiently. You can see them here at Tiny Tachometer.


Steering Valves


The steering valves used on Italian Tractors are commonly made by Danfoss. You may also see Eaton or TRW valves and perhaps others. Steering valves are not that complicated and normally quite reliable. We do carry new replacement steering valves in stock for about $500. What does tend to fail after many years are the seals and there is no reason why you should be discouraged from replacing seals or overhauling the pump if it fails. You can purchase parts or rebuild kits from:


Midwest Steering  Midwest Steering will also overhaul valves for those not interested in doing it themselves. If you look on our resource and manual page, you will find overhaul manuals for a few of the common steering valves.


Fuel and shut off cable


The accelerator cable and fuel shut off cable are often damaged, broken or missing on older tractors. The accelerator cable is normally terminated at the throttle control housing with a more or less standard set up. There is often a small bracket that terminates one or more cables, which is easily made up if missing. Note the bracket is held in place by the lower adjuster.
















This is the basic set up on the Lombardini 914 engine, common to the Pasquali 988 and various other tractors. You can see the accelerator cables and the fuel shut off cable lay out.


Cleaning the Cooling Shroud


Interestingly enough, cleaning the cooling shroud doesn't seem to be a high priority for owners. Remember, they are air cooled. Air is blown into the shroud by the fan and exits out the other side of the engine over the cooling fins. This removes the heat from the cylinders. Without adequate cooling, rings fail and the engine will start burning oil. Here are two reasons why it's good to remove the shroud and check: