Combines 84 N6 underhaul IJ s

[Dr_Allis]

84 model already has the slowdown pulley. 81's and older ran 2800 rpm.

 

[Rig]

I did my 84 last spring. I found the AGCO information with the new bearings and bolts to be confusing. Make sure you understand it. Adjust your valves and do the injector check unless you have info that it has been done lately. I find that most diesel shops, anymore, just replace tips so this is an expensive check. Check for weep oil at the oil cooler also. These seals last about 20 years. Its a great time when the motor is out to blast out all the dirt in radiator fins.

 

[sidekick]

Back in Oct 04 Tbran listed ptn 70277489 as new rod bolt for 426's made by ARP.Much better quality than before.Might want to use them while your there.They won't stretch_fatigue like originals.

 

[jbull]

I'm not a diesel mechanic but I've been told an underhaul isn't that complicated. Is that trueIJ Not sure I want to tackle this job by myself. I have access to a hoist and front end loader to remove the engine. My dealer said it should cost $1200-$1500 for parts and labor on just the underhaul. John

 

[rbryl]

If you can find a pully to slow down the engine go for it. It will add longer life to your engine. You will not lose any power because of the torque curve.

 

[Rig]

I would say it is fairly complicated. The engine is heavy and I was worried about making a mistake and ruining a motor that was still doing well. I have also heard of a number of motors putting rods through the side of the block at about this hourage due to rod bolt breakage and that convinced me to do it. There is also an issue of aligning the back of the motor correctly. The motor is mounted on a slotted frame. I marked things and also used the offical Allis tool rented from a local dealership to check the alignment. I gained about 5psi in oil pressure (hot) and it seemed that the bolts had lost some of the original torque setting. Aligning the rod caps with slightly torqued bolts with a sideways hammer tap is something I learned after seeing excessive rod thrust wear in a JD motor.

 

[sidekick]

I hope that price is them doing it all with you just getting it to their shop.If it's your first attempt at working on engines,you may be money ahead to let them do it.Don't need to get learning experience on something you have to count on when harvest is ready.

 

[jbull]

I think I'll probably let the dealer do it, I like to do as much as I can but this probably a bit much for me. Thanks for the comments. John

 

[sidekick]

I didn't mean to discourage you.If you have done mechanical repairs on other stuff it's not so different.Get a factory service manual for that engine and study the details before you begin then constantly reference it as you go along.Changing rods and mains isn't difficult.With a good manual you can work on most anything.