4650

[fixerupper]

Bought a 4650 with 9000 hours the other day. I'm fairly familiar with the Deeres of that era but I've never been close to a 4650. Are there any quirks to look for? I rented this tractor for 75 hours last spring and it pulled and ran fine and didn't make any extra noises. The power shift seemed to shift like it should but I'm not totaly familiar with the 15 speed. The only leak is a slight seep on the left side of the head gasket. Someone told me the cam gear wears fast but I thought that was only for the early 30 series. The outside appearance is very good and the inside of the cab is in good shape so I have an idea the previous owner drove it himself and paid attention to the details care-wise.

Anyway, I bought it right so if something major does need work I won't be under water with the value of it. Jim

 

[4010 puller]

Yea, the cam gear/oil pump gear would be on the early 40's, yours has the crank driven oil pump which is good. It should be a good tractor, it does only have the 1000 rpm doesnt it? Sounds like you will be using it for field work so it probably wont matter. If its just leaking a very little oil out of the head area in the rear that seems normal when worked hard.

 

[fixerupper]

Field work in the spring and fall and Gnuse bucket in the winter.

No more Gnuse bucket on the gear grinding slow hydraulics 1086 LOL! Jim

 

[Anonymous-0]

Pay attention to the weep hole on the water pump, if it gets covered over with grease or is seeping a little bit it can get plugged. Once plugged the leaking coolant gets past the lip seal and into crankcase. While up front look at the hydralic pump drive and see if the waffle(black cushion) is loose. If needs replacement replace the waffle and both halves, and ask on here for help then on disassembly. chris

 

[HubbTrac]

4650 is a great tractor in my opinion...I've worked on lots of them over the years..the gear drive water pump as someone else mentioned is the biggest weakness on the 50 series..I just pulled the head off one the other day for the same seepage issue you mentioned..If it bothers you, have the head resurfaced and put back the newer style head bolts with the flange head and tighten them using the torque-turn method and you shouldn't have any more issues with it..

 

[4010 puller]

Why is the gear drive waterpump weak, can you give me more info? Is the turque turn method like 125ft/lb, then 1/4 turn?

 

[Anonymous-0]

The weak part of the pump is that if the coolant seal in the waterpump starts leaking and the weep hole is plugged the coolant gets pushed past the oil seal and into the crankcase. The pump comes with a sponge plug to seal debris from getting into the weephole but actually increases the chance that the weephole will get plugged shut. I never put the sponge plug back in when rebuilding the waterpump and have dug the sponge out if I was working in the area. chris

 

[Tx Jim]

matthies
I agree with his statement. For the life of me I can't understand why the engineers elected to drive the water pump off the camshaft gear. My 4255 dumped coolant in the crankcase at 4500 hrs.

Since then my 4255 gets the engine oil dipstick checked every time the engine is started when it hasn't been running!!!!!!!!!!

 

[tim s]

Deere was trying to take the fan belt tension off the water pump bearing, I think it was a bad idea too, I have heard of people O/H ing engines thinking they had a liner failure only to find out later the water pump seal was the problem all along...

 

[Tx Jim]

I think I'd rather overhaul the waterpump more often than have to worry about the crankcase getting coolant in it from a leaking WP.

 

[tim s]

I agree, it seems that other engine makers are also going to cam driven pumps...

 

[fixerupper]

Thanks for the information. I'll check the water pump. The head gasket seep is anti-freeze coming out mid way between the front and back of the head on the left and it only seeps half way down the block so it isn't much. I looked at other 4650's with fewer hours but I felt more comfortable with this one since I've run it long enough to find out if there were any quirks. My philosophy is a 5000-6000 hour tractor might be ready to have some drive train/engine problems where a 9000 hour tractor has either had those problems fixed or it's just a good tractor. This thing will only be used for 75 hours pulling a 27 foot field cultivator and possibly a few hours with a 5 shank Deere V Ripper in the fall. If we don't have much snow this winter it will be seldom used but if we have a winter like last winter it'll run every day. Jim

 

[fixerupper]

I replaced two gear driven water pumps on Lexion combines with cat engines last September and replacing the Deere pump has gotta be easier than the cats, and the tractor's on the ground, closer to the tool box. Jim

 

[Heavyduty1]

(quoted from post at 15:52:10 12/10/10) I replaced two gear driven water pumps on Lexion combines with cat engines last September and replacing the Deere pump has gotta be easier than the cats, and the tractor's on the ground, closer to the tool box. Jim

I replaced a water pump on a 4055 with the 466 and only removed the fan/clutch to get the water pump out. I went with a reman from deere and it was about $260. It was not bad but not easy either. :wink:

 

[HubbTrac]

When the seal goes out it dumps coolant directly into the base if the weep hole on the pump is plugged which it almost always is..I don't know how many times exactly I've seen this but it has been quite a few..which is why I consider it to be a weakness...major engine failure can result pretty quick as a result..I don't have the book right in front of me but yes it entails tightening to a specific torque and then tightening so many degrees...scribe a mark on the bolt head to gauge by..I can get you the exact numbers if you'd like..

 

[4010 puller]

you dont have to get me the exact specs on the head bolt torque, I think its the same as doing the 404 engine, 125 ft/lb, the 1/4 turn.

I was looking at a 6076 engine (was a power unit, I wanted to put in tractor). Owner said it was leaking antifreeze in oil, he thought it had bad liners or orings, I just wandered if it could just be the water pump after hearing of the gear driven type fail.

 

[HubbTrac]

I would definitely check the water pump first...as someone else said, a lot of people rebuild engines thinking the liners are bad when it's only the water pump putting coolant into the oil.. 6076 is a tough engine..just the metric version of a 466..6 cyl 7.6 liter... I rebuilt one (power unit) for a guy a few years ago with over 11,000 hours on it..he was just worried about the hours, the engine wasn't giving any problems..there wasn't enough wear in the cylinders to hardly measure..of course keeping the oil changed helped too..

 

[4010 puller]

I'm wanting one for a puller project. The best things about the 7.6L is the crank driven oil pump and the better (so called 55 series) cylinder head.