help installing piston needle bearings

[gmerz]

Can somebody tell me what is the proper method to remove and install cageless piston wristpin needle bearings? Is there any special tools involved?

I need to change a piston on a 787 engine and noticed the bearings are cageless and I am wooried about bearings falling into ccase. Also how many bearings should be on each side when it is apart?

[Tom XP]

Re: help installing piston needle bearings

There is a tool for that, but I did mine by using some grease to hold bearings in place and some patients.

I believe there are 36 needle bearings.

[John Kubiak]

Re: help installing piston needle bearings

BRP/Sea-Doo has a special tool that is relatively inexpensive, and can be easily used to remove and install the needle bearings and has an added benefit of helping to hold the piston in correct alignment to avoid damaging the needle bearings and/or the thrust washers while installing the wrist-pins in 717 and 787 engines; Sleeve set P/N 529 035 542 (20 mm sleeve 2pcs and pilot 1pc).

There are 34 needles per bearing on a 787.

[braap]

Re: help installing piston needle bearings

Are the thrust washers needed if replacing the bearing with a caged version?

[Technical Support]

Re: help installing piston needle bearings

No.