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We’re not looking at the same figure.Bearing box fig 12 part number 875425
sealing washer #21 part number 832675 pay attention to shims in the washer!
Then swiftly place the boat on CL and runaway as fast as I can..Once you get it correct then you can install the seal and O rings, put the bearng box back in the clamping collar and then install the u crosses and torque the yoke into the gear.
I have the factory service manual for my drive and engine. But like all service manuals, there’s the long drawn out correct procedure (often requiring special tools and fixtures), and the one that works just as well.
Much of this work can be done without the special Volvo Penta tools. We call that Improvising!
A lot of these manuals assume you know your way around an out drive already.
Yes.
I’ve got four shims that came out of this thing.
You mean from within the seal surface washer?
I picked up a new seal (#21), and o-ring (#19).. but if you’re telling me I need MORE rings, please let me know.
In order to completely over-haul a 280 transmission, you will need a total of 8 O-rings, one top cover Looped-Gasket, and one red phenolic gasket for the fill plug.
Sounds to me like all this spinning torque stuff is simply stating it must turn true and freely.
Back-to-back tapered roller bearings require a pre-load. The pre-load is measured via a rolling torque value.
Too tight...... and the rollers may burn.
Too loose ...... and the rollers may chatter and begin self destructing.
The manual will give you a rolling torque value for NEW bearings, and for what we call "run-in" or used bearings.
With run-in bearings that are still good and operational, you can safely remove .001" from that shim pack.
I’ll do the checks as best I can, but really didn’t want to do so much disassembly on this thing. I realize the need to do it “right”, but it’s hardly the space shuttle. The likelihood is very high that I will only keep the boat a year or two, or until I leave this darn state.
If you can polish the seal surface washer, and bring the seal's surface back to life, you will not need to concern yourself with the shims.
I refuse to fight with the crosses if they’re hard to disassemble due to the rust (haven’t tried them yet), I’ll just let my engine rebuilder guy do it.
Once the universal drive shaft is on the bench, removing and replacing the bearing crosses is not that difficult.
Much of this can be done with a large bench vice and a brass hammer.
In you manual there should be a pic of the bearing box with a string wrapped around it. Once you know the procedure it is real simple.
That is correct for the 280 with the steel bearing box.
When the string is pulled on, the energy needed to rotate the BB is measured in pounds, as though weighing something.
(the later style all aluminum integral bearing box is measured very differently)
The yoke should not spin free clamp in in a vice and torque the bolt with the four shims under the washer wrap the string around the bearing box and pull on the string if should move when you exert about 1 lb pressure on the string.
Technically this is done with the male yoke installed into the drive gear, and with the single bolt torqued to the correct value.
The seal is not yet installed.
Any hanging fish scale will work.
I would suggest using a more precision scale.
If it turns easy remove one of the thinnest shims torque the bolt and try again.
I would suggest removing only .001" value and trying it again.
Once you get it correct then you can install the seal and O rings, put the bearng box back in the clamping collar and then install the u crosses and torque the yoke into the gear.
That will work. However, I do just the opposite.
I R&R the bearing crosses while the universal drive shaft components are on the work bench.
I have found it to be much easier this way.
Ricardo, would you please explain this step in a bit more detail? Thanks....Ricardo said:Once installed, be sure to tap the yokes correctly as to relax the trunion bearing caps.