1996 780 Fuji Rebuild

[BlueFishCrisis]

Thought I would try and document my rebuild of a 1996 780. Not exciting for most, but maybe for some of the newer members. Tear down, disassembly, and labeling of all parts already complete. Please feel free to correct me if I state something incorrectly or do something wrong......

Day 1 - About 1.5 - 2 hours of work with some cleaning / prep.

Start with a clean matched set of crankcase halves. All mating surfaces to be clean and free of oil, grease, residue, old gaskets, etc. I use a green scouring pad to accomplish this as seen in the background of the top half picture.

[BlueFishCrisis]

Very important to clean out the grooves where the new oil seals will seat. These will probably have sealant stuck in them from the previous seals. This will help to be sure that the new seals seat nicely and neatly in the grooves



Now is also a good time to check your pulse fitting and clean it out.

[BlueFishCrisis]

You will also notice an opening in the bottom half of the cases, one in each cylinder location, for a drain. Unscrew these bolts, clean the threads, and make sure the passages are clean as well.



The rectangular block out in the section between the CEN and PTO is the void where the oil pump gear is located. While the oil pumps are quite reliable, I have chosen to install a block off kit on this motor.

[BlueFishCrisis]

On to the top half of the crank case...... These notches need to be cleaned out. There are pins on the crank bearings that sit in this notch. You will want to be sure you locate the pins and have them positioned correctly when placing the crankshaft in the cases.



Once both halves are cleaned and ready, I have applied a small bead of Threebond 1211 to the bottom half of the cases.

[BlueFishCrisis]

I like to use a little extra in the grooves for the seals to be sure that they are completely coated.



Slide the oil seals on the crank shaft and carefully set it in place. Note where the pins are on the bearings. The PTO bearing has a ring on it that fits into a groove in the cases.



I did not get a photo, but next I set the top half of the crank case over the bottom half. I used 1211 on the seal grooves only for the top half. You will need to hold the rods up to get them through the top half of the case. An extra set of hands makes this easier.....

[BlueFishCrisis]

Next, I temporarily re-install the MAG and PTO jugs and secure them lightly with two base nuts. I flipped the cases over to access the case bolt holes. Then using threadlocking compound, I dropped each bolt into its respective hole and tightened in the sequence and torque value as called out in the Polaris service manual. Be sure to rotate the crankshaft periodically to make sure it doesn't bind.



Last activity of the day was to start to prep the jugs for install. I noticed something curious in the exhaust passage at the ports.... This occurs in each of the 3 cylinders in the exact same location / formation. Any comments???




More to come......

[Polaris_Nut#1]

Last activity of the day was to start to prep the jugs for install. I noticed something curious in the exhaust passage at the ports.... This occurs in each of the 3 cylinders in the exact same location / formation. Any comments???

[ATTACH=CONFIG]295482[/ATTACH][ATTACH=CONFIG]295483[/ATTACH][ATTACH=CONFIG]295484[/ATTACH]


More to come......

Mine were the same, I noticed it after honing the cylinders. When I spotted the first one I thought it was a crack but the are all like that.

[ripcuda]

Nice! I appreciate a good pictorial. Thanks for your efforts.

I'm contemplating doing the same when I put my Weber MPE750 back together... but it's a lot of effort for the 3 people that might ever need it. Haha!

Cheers!

[Drkvampire2001]

Is this the engine that will be going in my SLT750 Hull?

[BlueFishCrisis]

Is this the engine that will be going in my SLT750 Hull?

Perhaps.... but not sure yet....

[Mr. GP1800]

Are you having ported cylinders done? Make that baby rip!!!!!!!!

[K447]

Nice! I appreciate a good pictorial. Thanks for your efforts.

I'm contemplating doing the same when I put my Weber MPE750 back together... but it's a lot of effort for the 3 people that might ever need it. Haha!

Cheers!

I have learned that having really well done online resources helps a lot more people than you might think. For every person that actually joins and provides comments here, there are others who will find and use the info, but may not become visible on the forum.

They WILL be visible out on the waterways, lakes and rivers, riding their properly repaired machines!

[BlueFishCrisis]

Are you having ported cylinders done? Make that baby rip!!!!!!!!

Probably not on this go round..... maybe on the next one.

[BlueFishCrisis]

Day 2 - Mostly spent prepping the cylinders for installation. Cleaned them up and then lightly honed / deglazed. This took about 1.5 hours for all three jugs. Cleaned all contact surfaces, and cleaned / siliconed the jugs themselves. Still need to wash out and re-oil the bores.

[auto culto]

this is very helpfull, just hoping I wont need it for reference any time soon lol