Cooling fan advice
 

Hi All, I am going to attempt to replace the cooling fan on my 1650. There seem to be two approaches, slide engine forward or drive out the roll pins. Both seem involved, recommendations of time vs experience will be appreciated. Personally I have more time available than experience.
Thanks
Eric

Personally, that is the option I would take.

I think I would pull the engine. Unless you had a catastrophic failure with your fan, and it has been replaced lately, I am going to guess that the flanges on each end of the drive shaft, connected to the flex joints, are stuck to the shaft pretty well, and will require heat to separate the shaft from the flanges. I used anti-sieze grease on the end of the shaft when I re-installed the flanges with new roll pins from Caterpillar.

With my new fan, I had a little trouble getting the snap ring to hold the fan in place. Along with a heavy snap ring from Caterpillar, I also used a little bit of black silicone to glue the fan to the shaft. Be sure to check the service manual for proper spacing between the fan hub and the connecting flange. I think it is 1 1/8".

Pulling the engine also gives you the chance to tighten the front axle in its carrier, and adjust/rebuild the steering sector as necessary. You can check your ISO mounts, snubbers and do the engine cradle modification if you haven't done so already.

Just did this yesterday on my 1650 - drove out 2 rear (1/4x 1 3/8 Fastenal # 0161761) COIL pins. COIL pins take a special punch that has a raised nipple in the center, it starts the center moving first - this relieves of friction. Pull up on the shaft with a hoist to take the pressure off the Hydro and give it something solid to punch against. Took me 10 minutes - just slide both coupling forward with the flex discs intact ( clean the shaft with emerycloth first) then lift up shaft (flexes on motor flex dsic) and slide coupling off. I would order 4 coil pins first (.50c ) , they tend to stress fracture over time. Also change the Hydro seal while your at it National (#471466) for $5.67.