787 Countershaft Bearing Replacement How To

[treetopflyer737]

Anyone have a quick and easy method of replacing seals and bearings on a 787 countershaft without having to buy the seadoo tools? I live close to a harbor freight if anyone has used a setup from there-

I am in the middle of a complete rebuild on (2) 787 motors that are getting new cranks, cylinders, pistons and figured it would be good time to change the bearings and seals on the countershaft assembly.

 

[treetopflyer737]

Also, would you guys recommend doing the rotary shaft bearing and seal as well?

 

[mikidymac]

You would need a hydraulic press to get the weight off to replace the bearings and seals but make sure you mark it precisely before taking it apart.
I replace the bearings on the rotary shaft too.

 

[Sloanman7]

just get a rebuild from sbt 89.00 bucks

 

[treetopflyer737]

the bearings and seals cost me $9.00, why would i do that.

 

[ski-d00]

because it's not easy to get the bearings and gear off and back on without the proper tools, that's why. at a minimum, you will need a bearing puller to get them off. HF does have a bearing/gear puller set but I'd say it's unlikely that it will work. Even if you get them off, getting them back on in the proper balanced location will also be very difficult. You could take to your local machine shop but I'll bet they charge more than SBT.

 

[treetopflyer737]

Damn, both bearings feel great however I see a very very thin piece of rubber seal that squished when cases were assembled. Doesn't seem to me that these seals would have a detrimental effect if small leak started considering they are not inside/outside sealing washers, correct?

 

[racerxxx]

To remove the bearing you need a 2 jaw puller----NOT a 3 jaw. You can't fit a 3 jaw by the gear and counterweight. Unless the seal is tattered I would let it ride. But to do the seals you will need a hydraulic press.


Look thru my resto threads in my sig line. in one of them I show the break down and I think the tools I use. I post that crap so guys can see how they can do it at home. To do the rotary shaft bearings you will need to pull the internal bearing with a blind hole bearing puller, got mine at harbor. Again, you can see a lot of this in my threads. I'll have limited access to the forum this weekend.

 

[racerxxx]

Here is some of it

http://www.seadooforum.com/showthre...ugar-and-Spice&p=408997&viewfull=1#post408997

 

[treetopflyer737]

Racerxxx, thank you so much! Super helpful information!

 

[treetopflyer737]

You do beautiful work by the way!

 

[treetopflyer737]

So I figured I'd contribute my two cents to my thread-

Here was my solution for getting the bearings off with some pictures.. I picked up a $12 (3 piece) 2 jaw puller set from harbor freight that worked beautifully. I started by taking a punch and knocking a dead center punch on both ends of the countershaft end. This allowed the center point on the 2 jaw puller to stay nice and straight. Set up the two arm puller on both ends and bearings come off with ease. Machine shop down the street removed the gear for me for a $10 tip.

NOTE: Ordered SBT Chinese replacement bearings for the counterbalance shaft and am not happy with the quality! There is already a small amount of play on the inner races of the brand new bearings! Called SBT and tech guy confirmed that their countershaft bearings have a small amount of play however they have not experienced any issues with them.

 

[mikidymac]

SBT used to be good in my opinion when their prices were cheap and you knew what you were getting. Now their prices are almost getting up to OEM levels with questionable quality. I will always use OEM parts when they are deep inside my engine and a pain to get to. My $0.02.

 

[racerxxx]

I buy skf bearings either on Ebay for dirt cheap (old surplus), or if I can't find then there I go 2 miles from home to the bearing house I use. Bearings are something I'll never cheap out on. You can't get the exact ones that came off, they're in stock in Europe, not the U.S. , so I use the closest skf I can find

 

[mikidymac]

I just order OEM from Pro Caliber and have them is less than a week.