case 680E motor swap

[Briankos]

I have seen some post from many years ago about the case 336 motor. Well unfortunately for me, yep, no research, I bought a 1978 case 680E 2wd backhoe non turbo, with the 336.... used it 5 or 6 hours and she died. Just stopped. clunk. to make a long story short, drained oil and found brass in it..... my opinion without opening the case, spun bearing. Now going through the forums I see that I may be better off just changing the engine out..... any suggestions as to what I may put in for a "bolt up" application? Not sure if this motor is repairable and at what cost as opposed to buying another size motor

 

[jon f mn]

Not much made to exchange there. The
smaller motor from the 770 is a direct bolt
in. And with some mods the 7/830 motors are
the same size and will bolt in. But all
those are significantly lesser motors. Im
sure they would all work fine, just have
less power. Except for the crank, those 336
are common parts and easy to get so an
overhaul may be your best bet. All the
parts in the 336 are the same as the small
journal 504, just 2 less.

 

[Roger Link]

The 336 has 3 different crankshafts, the early one has the same size rod and main bearings as the 1370 and other high HP 504's, The later ones have the small journal cranks like 770,730,830, and there is also a crankshaft that has splines on the front nose, this is very uncommon. You should pull your motor to see what you have 1st, It may be repairable, the balancer mite have failed causing the damage, Don Livingston may have a balancer, mite as well open it up and see what you got.

 

[Briankos]

(quoted from post at 00:04:20 09/17/22) I have seen some post from many years ago about the case 336 motor. Well unfortunately for me, yep, no research, I bought a 1978 case 680E 2wd backhoe non turbo, with the 336.... used it 5 or 6 hours and she died. Just stopped. clunk. to make a long story short, drained oil and found brass in it..... my opinion without opening the case, spun bearing. Now going through the forums I see that I may be better off just changing the engine out..... any suggestions as to what I may put in for a "bolt up" application? Not sure if this motor is repairable and at what cost as opposed to buying another size motor

Well, after finally pulling the motor out and having a mechanic take a look. whoever owned the backhoe before me hade the motor rebuilt recently. Problem was that the JERK who rebuilt it left 2 connecting rod bolts loose. Found the 2 rod bolts in the pan. Crank junk, rod bent, 2 valves bent and a crack in the block. 1 minute of work caused thousands in damage.

 

[Briankos]

Thanks for the reply. This particular motor has the spline on front that drives the hydraulic pump. Ended up buying a whole machine that had a bad tranny, just to pull the motor for my swap. Have plenty of spare parts now! Was told that the 336 is a very strong motor, and the machine was worth saving. Hope so.... Plenty for my own yard work.

 

[Briankos]

Thanks for the reply. Ended up buying another machine to salvage motor. Check the other posts and you will see why.

 

[Briankos]

I bought another machine with the exact same motor, now for a swap.... the 1st one I stripped down to block and heads before pulling it, and found that there is 1 bolt in the front of the engine holding it, and somewhere around 10 or 12 bolts around the bellhousing, then some miscellaneous houses and wiring and cables. if you have pulled this engine before, how far do I really need to go to swap it out. Do I really have to take off the compressor, air tank, manifolds, etc, or is there a couple places to sling it or put chain hooks to get it out?

 

[Currencia]

The air tank, compressor, alternator and air cleaner are the easiest things on the engine to take off. Why risk damaging them while you fight with them to pull it as one piece? All of them come off in 20 minutes total. (Leave the intake manifold.) They will give you the most room to pull the engine. Thread some eye hooks where the valve cover bolts go. Take out the fan and the radiator. They are just as easy to pull. Now you have all the space you need (and then some) to pull the engine & tranny out as one piece if your standby tractor bucket can lift the weight which I estimate to be 4,000 pounds.

I need an oil pan that is in good shape for a 680E 336 engine. tele 715 541 2740. Interested? call please.

This post was edited by Currencia on 11/01/2022 at 09:11 pm.

 

[Briankos]

Okay, Motor is swapped.... got everything in and all hoses etc connected. There are about 10 bolts to separate the bell housing to the motor, including 4 from the starter. Also 1 main motor mount bolt in the front, under the hydraulic pump... 1 1/8 nuts. 2 brand new batteries fully charged, and I am now having a problem with starting it! No crank, not even a click. Anyone have the wiring diagram for the 1978 Case 680 24v starting circuit? maybe pics of the wiring? Much appreciated for even looking!

 

[Briankos]

I didn't pull the tranny with it because the donor tractors tranny was bad. No forward.

 

[Briankos]

I'll see what I can do with the oil pan. I may be able to get it back. I have all other parts of this tractor available (Except the engine) including the compressor and hydraulic pump, radiator, intake and exhaust manifolds, water manifold, all hydraulics and pistons.

 

[Currencia]

(quoted from post at 18:00:54 11/13/22) Okay, Motor is swapped.... got everything in and all hoses etc connected. There are about 10 bolts to separate the bell housing to the motor, including 4 from the starter. Also 1 main motor mount bolt in the front, under the hydraulic pump... 1 1/8 nuts. 2 brand new batteries fully charged, and I am now having a problem with starting it! No crank, not even a click. Anyone have the wiring diagram for the 1978 Case 680 24v starting circuit? maybe pics of the wiring? Much appreciated for even looking!

I will make you a service manual if you can get me a good oil pan.

For starters (excuse the pun) with the problem you just described: discon the batteries you just put in from the wiring harness. Run the 24V positive directly to the starter solenoid and add a red control wire to the injector pump solenoid to provide fuel to the pump. That engine should fire up. If the starter or solenoid does not utter a peep, watch for smoke or very hot wires at the starter. If so, your starter is toast. Pull it and bench test it to see if it will spin when not installed in the 336. If it spins on the bench, but not on your 336, the crank is stuck.

This post was edited by Currencia on 11/13/2022 at 05:05 pm.

 

[Currencia]

(quoted from post at 18:10:12 11/13/22) I'll see what I can do with the oil pan. I may be able to get it back. I have all other parts of this tractor available (Except the engine) including the compressor and hydraulic pump, radiator, intake and exhaust manifolds, water manifold, all hydraulics and pistons.

How much $ for the hydraulic pump please?

 

[Briankos]

(quoted from post at 05:12:52 11/14/22)

(quoted from post at 18:10:12 11/13/22) I'll see what I can do with the oil pan. I may be able to get it back. I have all other parts of this tractor available (Except the engine) including the compressor and hydraulic pump, radiator, intake and exhaust manifolds, water manifold, all hydraulics and pistons.

How much $ for the hydraulic pump please?

The oil pan is gone, and the hydraulic pump needs a front bearing. If you are still interested in the pump let me know....

Anyone have the wiring diagram for the start circuit for the 1978 680e with a 336 engine? The manual doesn't show wire colors from the key switch.