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AQ140/280 PDS bearing(s) question

T

taffkid

Member
I am finding some time to work on the AQ140/280 that I have posted questions about earlier this summer. I pulled the PDS and the bearing. There is another small roller bearing in the flywheel cover cavity past the forward seal and forward of the B/W splines. This bearing appears to be in good condition but there is not much grease up there. Nor was there enough grease in the rear bearing cavity and it appears that someone fairly recently installed a shiny new SKF bearing without sufficient lubrication and with the seal facing the wrong direction. I might have already dodged a bullet here and am replacing the rear bearing just in case. I have also tapped a grease zirk into the flywheel cover to replace the capped port so that should prevent future lubrication problems.

How is this forward bearing serviced and lubricated? Is there anything I should know about this bearing before re-installing the PDS with the new bearing and aft seal? The forward seal appears to be in good condition, should I replace it too?

I have the Volvo service manuals but I can't find any useful info about this bearing.

Thanks for your help.
 
The bearing in the flywheel is just a "pilot" bearing. It does not turn, just keeps the pds aligned. So don't worry about greasing, it won't make much difference if any.
 
What you are calling the fwd bearing is a ball bearing in the crankshaft. This is a carry-over from the Auto engine w/ standard transmission whereby this bearing did actually rotate.
In the Marine app, it is used for centering only as per Eduardo, and does not rotate (other than 1:1 with the crankshaft).
It could just as easily be a bronze bushing!
I would grease the center of it, and the B/W splines just to prevent rust.

The FWD flywheel cover seal installs in the conventional direction, however, the AFT seal installs in a non-conventional direction.
IOW, you will see the little tension spring when installed correctly.
This is so that it will breach seal as to prevent grease pressure from pushing the seal out of position.

The PDS bearing will be an "open" bearing since the F/C has the grease port.... (should be an industry standard 6206).
Pre-fill the grease cavity prior to the AFT seal being installed.

Good call on turning the grease cap into a zirk fitting.


.
 
Thanks for your replies. I have re-assembled the shaft, bearing, and seal after pre-filling the grease cavity and bumping the engine until grease came through the bearing.

I have a question about my exhaust bellows though. I replaced the old torn bellows with a Sierra bellows. The replacement has two flapper valves in it. When I run the engine the flappers and the whole bellows shake violently and the metal collar that holds the flappers makes a loud tapping noise like a failed piston ring. I nearly had a heart attack when I started the engine until I realized that it is the bellows making the noise. Is this normal? The old bellows did not have flappers and did not shake like the new ones.

Rick, I think I got the instructions for tapping the zirk from you. Everyone should be doing that, it makes greasing the bearing at installation a cinch.
 
Does your drive exhaust outlet have a flapper on it?
If so, there is no need for the bellows flapper, IMO. Too restrictive!

Also, the bellows flapper is not only directional, but it is index sensitive.
The steel hinge member will be vertically positioned.
IOW, the combination of the two flapper parts form an oval shape, and must be indexed correctly for the somewhat oval shape of the connection at the Intermediate housing.

It will also have a water weep hole that is to be placed at the bottom fwd area.
 
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I am pretty sure I had the flapper assembly indexed right. Is the intermediate housing port supposed to support the bellows flapper assembly? If so that might explain why the bellows were jumping around causing the metal flapper hinge to knock, if I did not have the housing side inserted all the way in.
 
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