7020 Overhaul or used motor?

If you overhaul it you know what you got. Getting a another motor is a crap shoot because it could have the same problems. I vote overhaul it and you will have a motor that’s lasts you a long time.

A used motor would probably come from a combine so there would be a lot of labor to make the switch.

Did you find your antifreeze leak?  While you have it apart, get your head checked over with a fine tooth comb by a reputable machine shop.  There's not a lot of material between the injector opening and the valves on the copper sleeved heads, so they like to crack there if the motor has been hot.  If your head looks good, I'd consider reusing it with all new copper sleeves and a valvetrain overhaul.  I believe the sleeves are available aftermarket now.  If your head has a crack, replace it with a D2900 head from an earlier tractor without the copper sleeves, if that is compatible with the 7020's intercooler connections (someone else can chime in on this).  As far as the motor, I would rebuild if the crank is still usable.  Otherwise, I would look for either a good std/std crank to put in your motor or a used low hour late 301 you can swap parts onto and rebuild it or if it is in really good shape, just freshen it up with at least new o-rings on the sleeves and bearings.  I don't think the 301 crank has a lot of meat to machine off compared to some of the other engines, but I don't have my service manual in front of me to see what the max was.  Just my 2 cents.  Easy for me to type when I'm not paying... so definitely do what you need to do to fit in your budget.

you could buy the used engine, pull the pan and put some new bearings in it before you install it.

Edited by Acdiesel - 07 Dec 2018 at 10:51am

Technically, it would take an M-3 engine @ 145 flywheel HP (intercooler) to match the 7020 engine for performance.  The majority of M-2's are @130 flywheel HP like a 7010 tractor. On the plus side, the 7020 doesn't have a hydraulic pump on the engine, so getting a combine engine to "fit" might only take making a couple of ears to weld or bolt to the timing covers front plate to attach it to the tractors side frames.

Does anyone know if a new crank is available for that engine,or any ALLIS engine for that matter? To the OP, I hope everything works out for you,I always wanted a 7020 myself.

My 7010PS has a combine engine now. Came to me that way. If it goes I've got a 12valve 5.9 Cummins here. Just saying.

Michael, I have not. That's good information to know.