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I have an appointment to look at a 646 tomorrow morning. He wants $1500 for it. Says he put a new hydraulic pump in a few years ago and hydraulics are strong. Said the engine is "tired" and is hard to start but runs fine once it does, I didn't ask about smoking, and the travel pedal does not come back up on its own but has to be pulled up. His diagnosis was that it is a broken spring inside a valve. Maybe a tear or two in the seat. It's 3 hours away and then I would have to rent a truck and a car carrier to bring it home, about $200 plus gas. So a total of 12+ hours of my time and $1750 +or-. He said he had another inquiry who was an "enthusiast" but could not make it this weekend and he opted not to hold it that long. We have a fairly large garden and put 8-10 yards of manure on it every year which I currently shovel into a small garden wagon pulled by a lawn tractor, and at 70 YO, it is not getting easier. I already have a decent condition 448 that I use to drag the driveway and pull small logs out of the woods and probably could sell that to defray some of the cost. Would appreciate any input or advice. Thanks, Larry
 

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'Tired' engine thats's hard to start probably points to low compression. That said, the price is attractive. Even with some major engine work you should be into it about $2500 or so, assuming you are your own mechanic. Usually rings and gaskets will bring an older Onan back to usable condition.

But, as you know, one can't be sure until it's disassembled and clean on your work bench.
 

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Discussion Starter #3
'Tired' engine that's hard to start probably points to low compression. That said, the price is attractive. Even with some major engine work you should be into it about $2500 or so, assuming you are your own mechanic. Usually rings and gaskets will bring an older Onan back to usable condition.

But, as you know, one can't be sure until it's disassembled and clean on your work bench.
What would rings cost approximately and how much of a job is it. I am familiar with tools and procedures. Got rid of my ring compressor years ago thinking I would never use it again. Larry
 

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Discussion Starter #4
Can anyone weigh in about the travel pedal problem? Is the spring inside the valve and if so, could you substitute an external spring somehow? Thanks, Larry
 

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There is an external spring that pulls the travel pedal back up. But its more likely the Banana plate is worn out and that's why the pedal is not returning.

the un official, how to Evaluate a CCI Loader is here: https://casecoltingersoll.com/showthread.php/81799-case-646-value?p=679009&viewfull=1#post679009

That tractor will fit in a Uhaul "5x9 Utility Trailer Rental with Ramp" and that's one of the only open trailers they will let you rent one way. Been there done that.
 

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Discussion Starter #8
There is an external spring that pulls the travel pedal back up. But its more likely the Banana plate is worn out and that's why the pedal is not returning.

the un official, how to Evaluate a CCI Loader is here: https://casecoltingersoll.com/showthread.php/81799-case-646-value?p=679009&viewfull=1#post679009

That tractor will fit in a Uhaul "5x9 Utility Trailer Rental with Ramp" and that's one of the only open trailers they will let you rent one way. Been there done that.

That is exactly the trailer I rented. The guy at the Uhaul said I would have no problem towing it with my 4 cyl Camry but I had reservations to say the least about towing 2400 pounds (1200 for trailer and 1200 for tractor) with a Camry so i drove the 30 minutes to my sons house and borrowed his wife Nissan Xterra which pulled it easily. We have our grand daughter visiting so the Nissan will go back with her tomorrow. I checked the compression with the PO's high end tester and got 125 pis on both sides, so I don't think the engine is particularly tired. pretty sure that the fuel is leaking back down so that if it sits for a week or so it takes a long time to start. It started instantly when I got home. So I'm confident that I can fix that easily. I'm pretty fried right now so i will look into the banana plate issue tomorrow. LP
 

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Congratulations! Great find at a great price.
Good call on getting the Nissan. That would have been overworking the Camry, IMO.
Can’t wait to see more pics.
 

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Good move on using the other vehicle. A BASIC 646 tips the scales at 1500 pounds. All decked out with fluid in the tires and rear wheel weights the units can top 2,000 pounds easy.

We usually haul my unit around with an F-150.. We have a flatbed car hauler to put it on. Fun part of that was finding ramps for the trailer that could handle 2,000 pounds.. Bost ATV ramps won't cut it.

Some people :tango_face_surprise have moved these in the bed of a truck..
But its a tight fit and probably need a 3/4 ton truck..


That is exactly the trailer I rented. The guy at the Uhaul said I would have no problem towing it with my 4 cyl Camry but I had reservations to say the least about towing 2400 pounds (1200 for trailer and 1200 for tractor) with a Camry so i drove the 30 minutes to my sons house and borrowed his wife Nissan Xterra which pulled it easily. We have our grand daughter visiting so the Nissan will go back with her tomorrow. I checked the compression with the PO's high end tester and got 125 pis on both sides, so I don't think the engine is particularly tired. pretty sure that the fuel is leaking back down so that if it sits for a week or so it takes a long time to start. It started instantly when I got home. So I'm confident that I can fix that easily. I'm pretty fried right now so i will look into the banana plate issue tomorrow. LP
 

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Discussion Starter #13 (Edited)
After a few days with the new tractor:
I found a screen door spring that makes the travel pedal usable. Still some play in it but I want to use it for a while before I start working on it. Without any weight in the weight box, it lifted a full bucket of manure without hesitation. The PO said that the hydraulic system had hydraulic oil in it. I did not press him on whether that was an assumption or if he had put it in there but since he replaced the pump, I assume that he put at least some hydraulic fluid in. Is it critical that I replace it with motor oil right away? The engine oil was down below the fill line so i filled it up and tractor smoked when first started after that but has not smoked again. Since the compression is good, I'm not worried about that. It has started quickly every time so I'm convinced that the fuel is leaking back down in the line or maybe a tiny leak out of the bowl after sitting for a long time. That is exactly what my 448 did and a carb and fuel pump rebuild solved the problem. Finally, there is a short tube coming up out of the right side of the blower housing (page 18 of parts manual). It almost seems like there should be some kind of flapper valve over this but nothing in the parts manual that I can see. Any thoughts? And I almost forgot, the hour meter says 294. Obviously no way to know when it was disconnected but still better that if it read 2940. There is a nutted yellow wire behind the sheet metal, is that the wire for the meter? I could not even find the hour gauge in the parts manual. Thanks to all who weighed in with advice and encouragement. LP
 

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The reason Case and many other specify motor oil in the hydraulic system is because there is a "geo Rotor' hydraulic motor in the system. Most Skid steers also specify motor oil again because of the hydraulic motors in the system. Universal tractor hydraulic fluid is about he same viscosity as 15w - 40, but its missing the '-40" the lubrication package. So running hydraulic oil is causing more wear on the hydraulic drive motor. If someone put RED ATF in there that would be panic time.

I'm not following your reference to tube come out of the blower housing, so I marked up the attached diagram.
 

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Discussion Starter #15
The reason Case and many other specify motor oil in the hydraulic system is because there is a "geo Rotor' hydraulic motor in the system. Most Skid steers also specify motor oil again because of the hydraulic motors in the system. Universal tractor hydraulic fluid is about he same viscosity as 15w - 40, but its missing the '-40" the lubrication package. So running hydraulic oil is causing more wear on the hydraulic drive motor. If someone put RED ATF in there that would be panic time.

I'm not following your reference to tube come out of the blower housing, so I marked up the attached diagram.
Its the tube (opening) at the top left with "coil" written above it
 

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The OEM ignition coil was located in that hole, so the bottom end was in the air flow.. Supposed to cool the coil, but it also blocks air flow to the piston on that side. Make sure that the hole is blocked off. Its important to make sure all of the engine tins are on there so the pistons and heads get cooled.

The coil opening can be blocked with a PVC test cap, which is what I have in my engine.. Also make sure there is a rubber or foam seal around the engine oil filter to close up that opening so air does not escape their either.
 

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Older designed engines did not yet have the engine specs of today's engines. Most modern cars never need oil before it is changed. That was not the case in the '70s. In the 70's you needed to check your oil every couple gas fillups.

That puff of blue is normal. You are more going to follow how much oil it uses than anything else.
 

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Discussion Starter #18
The OEM ignition coil was located in that hole, so the bottom end was in the air flow.. Supposed to cool the coil, but it also blocks air flow to the piston on that side. Make sure that the hole is blocked off. Its important to make sure all of the engine tins are on there so the pistons and heads get cooled.

The coil opening can be blocked with a PVC test cap, which is what I have in my engine.. Also make sure there is a rubber or foam seal around the engine oil filter to close up that opening so air does not escape their either.
thanks for clearing that up. I was pretty sure it should not be open. I'll start saving up $ for that cap. LP
 
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