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AQ280PT drive shaft/double bearing

Sam C

New member
Hi everyone, I have recently purchased a Salem ski boat with a 350chev/Aq280pt package as a project. Totally new to boats so just learning along the way.

I have read over a lot of post which has given me a rough idea but was hoping someone could clarify some more specific questions.


I vacuum/pressure tested the drive after finding the oil had water in it. I found that the lip seal on the input shaft was leaking and it appeared that the boat had been used with a torn bellows. Fortunately it has only been used in fresh water.


After removing the outdrive and the double bearing box I have noticed some issues I would like to fix while it is apart.


The pds shaft has sealed bearings and the grease has been contaminated by the open bellows. I plan on removing the engine to remove the shaft so I can clean it out and start fresh with new bearings, seals and grease. I have found the information in regards to the correct parts/ installation in other forums. Can I do this with the bell housing still in the transom shield?


The universal joint crosses feel a bit stiff so I am also going to replace them while it is apart. I have seen the Spicer 5-1306x recommended but they seem to be an obsolete part. So I was planning on using another 7260 series cross with the same dimensions the spicer 5-789x, it just isn’t greaseable but the current ones aren’t anyway. Is there anything I should be weary of when finding a replacement, also are the greaseable ones suitable (strength wise) for the V8 engine?


When I removed the clamping collar I noticed the four bolts didn’t have any washers, the parts breakdown shows them there. Should I get some to use when reassembling?


While the double bearing box is out I plan on inspecting/replacing the bearings. I think I have read they are 30207 and 31307 is this correct?


Reading the manual it gives a prestressed value for the assembly (2.5-5Nm for used bearings, I assume that Nm is actually just N). My understanding is that the value is checked with a spring scale to determine the amount of force required to initially turn the bearings from a stationary position. Is this correct? The current assembly had next to no resistance.


I don’t have all the Volvo Penta special tools referenced in the manual but assume I can just use some universal drifts and pipe to press the assembly apart, is there anything I should be cautious of when doing so?


Finally the bolt that holds the input gear to the input shaft is obsolete from Volvo but the manual states it needs to be replaced. It is 7/16 unf and judging buy the torque value it is grade 5. I’m unable find the socket head screw in grade 5.... has anyone used a higher grade or do the later model drives run the same size bolt as I can still buy them.

Sorry for all the questions, any help would be appreciated!


Thanks,


Sam







 
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Hi everyone, I have recently purchased a Salem ski boat with a 350chev/Aq280pt package as a project. Totally new to boats so just learning along the way.
The 280 PT will look like this:



I have read over a lot of post which has given me a rough idea but was hoping someone could clarify some more specific questions.


I vacuum/pressure tested the drive after finding the oil had water in it. I found that the lip seal on the input shaft was leaking and it appeared that the boat had been used with a torn bellows. Fortunately it has only been used in fresh water.
FYI...... the pressure leak-down test is performed with the oil drained.

OEM bellows are better quality.
Use the Euro style band clamps ONLY!
DO NOT use the band clamps that have the exposed worm screw cuts in them!

In the future:
.....raise the drive no more than need be.
.....store your drive fully down and aiming straight forward.

Doing so will extend the life of these bellows.


After removing the outdrive and the double bearing box I have noticed some issues I would like to fix while it is apart.
We seldom remove an entire stern drive for this work.
When going back together, install the Intermediate housing (with the lower gear unit attached) first, then the transmission last.
You will find this to be much easier.



The pds shaft has sealed bearings
If there is a grease port on the flywheel cover at the 12:00 O'clock position, these must be open bearings.

and the grease has been contaminated by the open bellows. I plan on removing the engine to remove the shaft so I can clean it out and start fresh with new bearings, seals and grease. I have found the information in regards to the correct parts/ installation in other forums.
The PDS is installed with the new 6206 on it, then the 6007 is installed after that.
The grease cavity will be pre-filled while turning the PDS.
Stop ONLY when you see grease exit the ball cages.
Now and only now will you install the two 35X62X7mm single lip Timken or TCM seals.

The FWD seal will be glued and staked in place. (if you lose this seal, no future grease will make it to the AFT bearing!

The AFT seal installs in the Non-Conventional direction! In other words, when installed correctly, you will be able to see the lip and tension spring.
Reason: we want this seal to breach any excess grease.


When greasing the PDS bearings in the future, do so with the engine at idle RPM..... (Dynamic -vs- Static lubrication)
Two or three pumps after or during the engine oil/filter change.


Can I do this with the bell housing still in the transom shield?
That would be your "Flywheel Cover", and yes, you can replace the PDS bearings while it is still installed in the transom shield.

If you remove the flywheel cover, the large rubber cushion rings should be replaced, as well as the triangulation alignment process must be done.


The universal joint crosses feel a bit stiff so I am also going to replace them while it is apart.
Good idea.
These bearing crosses are nothing more than an older Chrysler auto application.
Spicer 5-1306X is a good choice.


I have seen the Spicer 5-1306x recommended but they seem to be an obsolete part.
Yes, if you find them, they will be either over-stock or left over inventory.
I just found a few of them here;
https://www.ebay.com/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=5-1306x&_sacat=0

So I was planning on using another 7260 series cross with the same dimensions the spicer 5-789x, it just isn’t greaseable but the current ones aren’t anyway. Is there anything I should be weary of when finding a replacement, also are the greaseable ones suitable (strength wise) for the V8 engine?
My story regarding bearing crosses with or without grease fittings is a long one.
Perhaps another day!



When I removed the clamping collar I noticed the four bolts didn’t have any washers, the parts breakdown shows them there. Should I get some to use when reassembling?
Those four special OEM washers provide the sealing at the heads of the cap screws.
They seal against a very delicate shoulder.
Find them and use them!


While the double bearing box is out I plan on inspecting/replacing the bearings. I think I have read they are 30207 and 31307 is this correct?
Yes, and if you do replace them, DO NOT purchase Chinese bearings.
Purchase these in a good US, German or Japanese brand bearing.
Your transmission will use shims (as apposed to a crush sleeve/pre-tension sleeve) for the pre-load control.


Reading the manual it gives a prestressed value for the assembly (2.5-5Nm for used bearings, I assume that Nm is actually just N).
DO NOT follow instructions from a Clymers or Seloc manual.
See the OEM only.


My understanding is that the value is checked with a spring scale
Correct! A spring scale pulling on a string that has been wrapped around the bearing box.

to determine the amount of force required to initially turn the bearings from a stationary position. Is this correct? The current assembly had next to no resistance.
What we call "run in" or used bearings have little pre-load.
You will using the pre-load value for "new" bearings.


I don’t have all the Volvo Penta special tools referenced in the manual but assume I can just use some universal drifts and pipe to press the assembly apart,
This work can be done without the special Volvo Penta tools.

is there anything I should be cautious of when doing so?
Watch closely for the tiny little spring pin that aligns the steel bearing box.
This pin positions the oiling hole correctly.

Finally the bolt that holds the input gear
That would be your "main drive gear".

to the input shaft is obsolete from Volvo but the manual states it needs to be replaced.
While the OEM suggests that this cap screw be replaced with new, you can safely clean it up and re-use it.
Clean both male and female threads.
Use Loc-Tite on the threads when going back together for the final time.


It is 7/16 unf and judging buy the torque value it is grade 5.
NO..... this will not be a grade #5.


Sam

 
NOTE: the reason for the grease cavity "pre-fill" (while spinning the PDS), is to ensure that no air is left trapped inside of the cavity.
We want a full cavity so that any future grease is able to move the old grease from within the AFT bearing's ball cage.
I suggest using a high pressure grease, not the green/blue Marine wheel bearing grease.


Also, you can add an 18" grease gun extension hose to the flywheel cover grease port.
Some of the grease ports are machine threads, some are 1/8" TP.
The extension hose will be 1/8" TP.
If yours has the machine threads, they can be chased with a 1/8" TP tap.
Clean the debris out, and thread the hose into the port.
Now you can fasten the other end of this hose up near the top of the engine for easy access.
Do your pre-fill with this hose installed!


PDS grease gun extension hose.jpg
 
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I just did this entire procedure last season, and I have pictures of every single step along the way if there's anythin you need or any help you need. Rick helped me out drastically throughout the process and I learned a ton.

But, if there's anything you'll need reference pictures for or anything like that, feel free to ask and I'll happily post whatever you need.

My setup is a 305 (AQ225D) with AQ280-PT, so it should be identical as long as you have the red flywheel housing too.
 
Hi everyone, I have recently purchased a Salem ski boat with a 350chev/Aq280pt package as a project. Totally new to boats so just learning along the way.

I have read over a lot of post which has given me a rough idea but was hoping someone could clarify some more specific questions.


I vacuum/pressure tested the drive after finding the oil had water in it. I found that the lip seal on the input shaft was leaking and it appeared that the boat had been used with a torn bellows. Fortunately it has only been used in fresh water.


After removing the outdrive and the double bearing box I have noticed some issues I would like to fix while it is apart.


The pds shaft has sealed bearings and the grease has been contaminated by the open bellows. I plan on removing the engine to remove the shaft so I can clean it out and start fresh with new bearings, seals and grease. I have found the information in regards to the correct parts/ installation in other forums. Can I do this with the bell housing still in the transom shield?
Yes, you can do this with the bell housing still in the shield. The hardest part is getting the large/industrial strength C-Clips out. So, use some super-strength industrial c-clip pliers OR be very careful when using other ingenuity to get them out as they are extremely strong.



The universal joint crosses feel a bit stiff so I am also going to replace them while it is apart. I have seen the Spicer 5-1306x recommended but they seem to be an obsolete part. So I was planning on using another 7260 series cross with the same dimensions the spicer 5-789x, it just isn’t greaseable but the current ones aren’t anyway. Is there anything I should be weary of when finding a replacement, also are the greaseable ones suitable (strength wise) for the V8 engine?


There are quite a few crosses that can be used/cross referenced. The ones I used for mine are MOOG 315g (2 of them) as they are Heavy Duty Semi Truck quality and they are identical to what was pulled out. Be careful on what orientation you put them in at before you clip them in finally, as the grease fitting will need to be facing an easily accessible direction should you desire to grease them every couple seasons or so when changing bellows.

When I removed the clamping collar I noticed the four bolts didn’t have any washers, the parts breakdown shows them there. Should I get some to use when reassembling?


While the double bearing box is out I plan on inspecting/replacing the bearings. I think I have read they are 30207 and 31307 is this correct?


Reading the manual it gives a prestressed value for the assembly (2.5-5Nm for used bearings, I assume that Nm is actually just N). My understanding is that the value is checked with a spring scale to determine the amount of force required to initially turn the bearings from a stationary position. Is this correct? The current assembly had next to no resistance.


I don’t have all the Volvo Penta special tools referenced in the manual but assume I can just use some universal drifts and pipe to press the assembly apart, is there anything I should be cautious of when doing so?
I did 100% of my entire outdrive rebuild, PDS main shaft refresher, and all other work without a single VP tool. Just be smart and think things through before you do them so you don't muck anything up by getting in a hurry, and you'll be fine.


Finally the bolt that holds the input gear to the input shaft is obsolete from Volvo but the manual states it needs to be replaced. It is 7/16 unf and judging buy the torque value it is grade 5. I’m unable find the socket head screw in grade 5.... has anyone used a higher grade or do the later model drives run the same size bolt as I can still buy them.

Sorry for all the questions, any help would be appreciated!


Thanks,


Sam








Hopefully this little bit of info helps.
 
[FONT=&quot][FONT=&quot]Hi Rick, thanks for the response. [/FONT][/FONT]
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[FONT=&quot][FONT=&quot]I didn’t consider removing the upper transmission only but it makes sense now you mention it. I will try it out when I re-install. Removing the whole leg did give me a chance to inspect everything so not entirely wasted which is good.[/FONT][/FONT]
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[FONT=&quot][FONT=&quot]There is a grease port on the flywheel cover so I will use the open bearings when re-assembling. I plan on using a high speed EP grease, is there any in particular that I should use?[/FONT][/FONT]
[FONT=&quot][FONT=&quot][/FONT]
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[FONT=&quot][FONT=&quot]Thanks for the link to the bearing crosses, I should mention I’m in Australia and they are much harder to find. Might just have to pay the freight to get them shipped.[/FONT][/FONT]
[FONT=&quot][FONT=&quot][/FONT]
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[FONT=&quot][FONT=&quot]I think the manual I have is the oem one, I attached a picture of the front cover.[/FONT][/FONT]
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[FONT=&quot][FONT=&quot]I’ll attempt to make some progress mid next week (next days off) thanks for all the information, it has been very helpful![/FONT][/FONT]
[FONT=&quot][FONT=&quot][/FONT]
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[FONT=&quot][FONT=&quot]Regards,[/FONT][/FONT]
[FONT=&quot][FONT=&quot][/FONT]
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[FONT=&quot][FONT=&quot]Sam[/FONT][/FONT]
[FONT=&quot][FONT=&quot][/FONT]
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[FONT=&quot][FONT=&quot][/FONT]0C554D8B-3BC4-4886-8F0A-26ECA4AD9FA6.png[/FONT]
 
Hi Walleye4days, thanks for the response.

Great to hear that you successfully did the rebuild, any information/photos you have will be appreciated. Ill keep this thread updated as i go. I'm sure I will learn a lot along the way.

Good to know that other crosses are an option, i did find a lot of suitable cross references to the spicer 5-1306x just wasn't sure if others had tried them.

I'm glad that the special tools aren't essential to work on the drive! I bought the boat as a project/hobby so I'm happy to take my time and just work my way through it.

Regards,

Sam
 
Sam, the OEM may give you several options for the rolling torque value and the procedure. Be sure to use the correct one and that you understand it.

One procedure may call out for a center-force rolling torque value (using the center bolt and an inch-pound torque wrench), while another one may call out for the string pull (string wrapped around the housing and with a weight scale).

It will also call out a spec for new bearings and for what they call “run-in” bearings.

Also, when removing the old large bearing (31307), you will need to cut the roller cage away, exposing the inner race.
This race will have a very small lip for a race puller fixture to grab. Often two weld beads must be added (180 apart) for the fixture to grab onto what is essentially a very small lip.

As the weld beads cool, they will shrink the race some, so get it into the press immediately before it has a chance to cool and shrink.


.
 
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Thanks for the tips Rick,

The prestressing (rolling torque) procedure was one of my concerns. The manual states:
3. Rotate the bearings a couple of turns to allow them to ”set”. Check the prestressing with a spring scale and a piece of string, tied around the bearing housing. The prestressing should be 5–10 Nm (3.69–7.38 lb.ft.). Should the prestressing be too low, press the roller bearing carefully a bit harder and if the pre- stressing is too high, release the roller bearing some- what.
NOTE! With run-in bearings the prestressing should be 2.5–5 Nm (1.84–3.69 lb.ft.).

My understanding is that with the string wrapped around the assembly it should take the specified amount of force to turn the bearings (vertically mounted). What I wasn’t sure about is whether this is the initial force required to start turning the bearings or should it be a constant as the bearing is turning as I see you refer to it as rolling torque? Also the manual has the value in Nm but I assume that just referring to Newton’s? I.e 250g-500g approx comparatively on the spring scale for run in bearings?

I did check the current assembly but found it had no measurable resistance on the spring scale. So I wasn’t sure if I was doing it wrong. Sorry for the ignorance but it’s not something I want to get wrong. Any clarification would be appreciated.



 
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In case you need this
http://www.jachtenonderlinge.nl/upl...p_manual_drives_280_280-dp_285_290_290-dp.pdf

Speaking with OLD mercruiser experiance you would oil the bearings , wrap about 6-8 turns of string around the shaft and hook up the fish scale and using a constant pulling read the Lbs on the scale.
All due respect Bt Doctur..... the string will actually wrap around the circumference of the bearing box, not around the shaft.
The Universal Drive Shaft would be held in a bench vice.

NOTE: On page 52, the manual shows the string pull being done on an "A" transmission.
The A and later transmissions use an integral Aluminum Bearing Box/Clamping collar.
The OP's 280 uses an all steel bearing box with a separate aluminum clamping collar.


Second method is to use a inch/lb torque wrench and a shaft extension
I’m not aware of any Volvo Penta conversion table for converting the rolling string pull method (in pounds of string pull) to a center-rotational torque value.
 
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Thanks for the tips Rick,

The prestressing (rolling torque) procedure was one of my concerns. The manual states:
3. Rotate the bearings a couple of turns to allow them to ”set”.
That is correct, and the bearings and the seal must be oiled.


Check the prestressing with a spring scale and a piece of string, tied around the bearing housing.
Correct! That would be the "bearing box".

The prestressing should be 5–10 Nm (3.69–
7.38 lb.ft.
The string pull measurement will be in pounds-of-pull.
Foot pounds would represent center-rotational-force.... as in a center-rotational torque rating that would be acquired by using a torque wrench.

The Volvo Penta engineers have done the math for us by converting this into a string pull measurement. I.E., string wrapped around the circumference of the bearing box.



Should the prestressing be too low, press the roller bearing carefully a bit harder and if the pre- stressing is too high, release the roller bearing some- what.

NOTE! With run-in bearings the prestressing should be 2.5–5 Nm (1.84–3.69 lb.ft.).
Your 280 transmission
(w/ an all steel bearing box) uses shims to control the bearing pre-load.
(the A and later transmissions use a "crush sleeve" aka "pre-tension sleeve")

These 280 shims are just inside of the "seal surface" washer.

AQ series early style seal surface washer.jpg

Reduce the shim pack value, and the rolling torque value will increase.
Add to the shim pack value, and the rolling torque value will decrease.

And yes, if the rolling torque value is too great, you will want to:

.... gently press (or drive against it with brass only) on the FWD end of the main drive gear (releasing the pressure by a few thousands only).
.... increase the shim value by .001" or .0015" .
.... re-assemble, tighten the bolt and test again.



My understanding is that with the string wrapped around the assembly it should take the specified amount of force to turn the bearings (vertically mounted).
What I wasn’t sure about is whether this is the initial force required to start turning the bearings or should it be a constant as the bearing is turning as I see you refer to it as rolling torque?
Correct!
This will be the force required once the bearing box begins to spin.
In other words, you will see a greater initial force required (to start the spin).
After the bearing box begins to spin, that will represent your actual rolling torque value!



Also the manual has the value in Nm but I assume that just referring to Newton’s? I.e 250g-500g approx comparatively on the spring scale for run in bearings?

I did check the current assembly but found it had no measurable resistance on the spring scale.
What you checked was your existing rolling torque value for your "run in" or "used bearings".
Depending on the engine's horse power and the hours of use on the transmission, often this value will be very minimal.

Imagine the work load that the 31307 bearing undergoes..... especially with V-8 power!







.
 
Thanks for the response Bt Doctur,

Fortunately I do have the manual but just wasn’t sure I was interpreting it correctly.
 
Ricardo, never worked the on volvo drives and never hope to but thanks for clearing it up for the poster.
Ricardo, the string pull method is very close to the rotational force needed. If there was a way to support the housing and turn the gear with a inch/lb torque wrench .
 
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..............
Ricardo, never worked the on volvo drives and never hope to
Ed, the AQ series VP is among the most user friendly to work on. I hope that you do get a chance to work on one someday.

but thanks for clearing it up for the poster.
You bet!

Ricardo, the string pull method is very close to the rotational force needed. If there was a way to support the housing and turn the gear with a inch/lb torque wrench .
There is a way to do that.

But I digress for a moment.
Both the bearing box circumference string pull and center bolt torque, create a rotational force that will allow us to gauge a pre-load.
However, unless you are a very savvy engineer, there is no published cross-over that I am aware of that would allow us to convert string pull (@ X diameter) to a rotational torque value.
In other words, if the string pull (wrapped around X" diameter bearing box) requires a 3.5 pound pull, that's how the engineers gauged it.

In order to use an Inch-Pound torque wrench on the center bolt,
I suppose that you could do the math and come up with an inch pound torque value!
I.E., X diameter bearing box X's string pull force = inch pounds torque.
After all..... 50 ft lb of torque = the force that would be created by placing a 50 lb weight on a horizontal bar that is connected to a bolt, not, rod, shaft, etc that is at a 12" radius from the center axis.

Here's a dictionary definition of one ft lb torque:
A pound-foot (lbf⋅ft) is a unit of torque (a pseudovector). One pound-foot is the torque created by one pound of force acting at a perpendicular distance of one foot from a pivot point. Conversely one pound-foot is the moment about an axis that applies one pound-force at a radius of one foot.

Here's the definition of one inch pound torque:

Similarly, an inch-pound (more correctly written as pound-inch) is the torque of one pound of force applied to one inch of distance from the pivot, and is equal to 112 of a pound-foot. It is commonly used on torque wrenches and torque screwdrivers for setting specific fastener tension.

SI units: ≈ 1.355818 N⋅m






Bottom line for the OP here........... stick with the string pull and scale for the 280 with the steel bearing box.
 
Hey everyone, haven’t had much time for the boat due to moving house, but the double bearing box replacement went well. While I had the upper transmission off I decide to give it all an inspection and have identified more parts in need of replacement. I was wondering if any one knows if the forward and reverse gear bearings are industry standard or do I need to buy Volvo penta. Trying to work out the cost involved before I press them out. Also should I replace the brass keeper with OEM or source a steel one.

Thanks for any help.
 
......................
...............

I was wondering if any one knows if the forward and reverse gear bearings are industry standard or do I need to buy Volvo penta.
There is no FWD or REV gear to speak of.
Either driven gear can be used for either FWD or REV, depending on how the linkage is set up regarding which hand prop is being used.

As for the double row angular contact ball bearings..... these will be OEM only...... and be prepared for sticker shock!

There is a similar cross-over bearing, but it will not work.

Trying to work out the cost involved before I press them out.
The main drive gear/bearing box must be removed.
Once the vertical shaft upper LH thread nut is removed, the vertical shaft can be removed.
The gear/bearing combination will lift out of the transmission case.
Watch for the shims and keep them in order.
The gear will then be pressed out of the bearing.

In most cases these bearings are so precisionally machined, that we do not need to change the shim values when we replace one.
Nonetheless, I would check the gear pattern once re-installed.

Also should I replace the brass keeper with OEM or source a steel one.
I would go with steel.
Here's the deal:
There was no OEM steel keeper for the 270, 275, 280, 285 or first gen 290. They were bronze only.
The OEM steel keepers came to be in/around the A and later transmissions. These are slightly larger on the ID.

However, years ago I had about 100 of the 270, 275, 280, 285 or first gen 290 split ring keepers made from stress proof steel. These were CNC produced.
I have some left over if interested.


AQ series split ring keeper damage.jpg


Be sure to keep both driven gears in the same locations as they were removed.

Thanks for any help.
 
Thanks Rick,

Shame that the bearings are oem only ( they are around $350 each here in Australia ). The brass keeper had been expanding and the top of the shaft had started to wear into the top cover! Safe to say I'm glad I decided to have a close look while I had the transmission off. Yes I would be interested in a steel keeper, can you send me a link or some way to purchase? When I press the gear back into the bearing is it safe to us the outer lip of cup if I have a plate to distribute the force.

Thanks again.
 
..........
Thanks Rick,

Shame that the bearings are oem only ( they are around $350 each here in Australia ).

Are you certain that yours need to be replaced?
If they do, then I'll bet that the main drive gear bearings (industry standard 31307 and 30207) also need to be replaced.... especially the 31307.


images
images





The brass keeper had been expanding and the top of the shaft had started to wear into the top cover!
You dodged a large caliber bullet on that one!

Safe to say I'm glad I decided to have a close look while I had the transmission off. Yes I would be interested in a steel keeper, can you send me a link or some way to purchase?

When I press the gear back into the bearing is it safe to us the outer lip of cup if I have a plate to distribute the force.
There is no "cup" with these bearings.
These are referred to as an "Angular Contact" bearing..... in a double row ball bearing style.

9k=


When pressing the driven gear into the bearing, the driven gear will be placed on a heavy plastic plate, and you will apply force the the inner race.
Very easy to do!


Thanks again.
You are welcome!
 
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The previous page would not allow me to post my image of the driven gear angular contact bearing.

Here is what it looks like.

As you can see, there is no cup as with a tapered roller bearing.
These have only double row inner and outer races.


AQ series driven gear angular contact bearing.jpg
 
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Thanks Rick,

I have replaced the main drive gear bearings. Sorry for my lack of terminology, the “cup” I was referring to was the cup on the drive gear where the engagement sleeve contacts. I will source some plastic for the job if I do it. I could possibly leave the ball bearings and just do the needle rollers. If I could of found a more affordable replacement I would of had done it for peace of mind.

Thanks!
 
...........
Thanks Rick,

I have replaced the main drive gear bearings.
Good. Make sure that you set the rolling torque value properly.
For the 280 steel bearing box, you will use the string pull and scale method.

Sorry for my lack of terminology, the “cup” I was referring to was the cup on the drive gear where the engagement sleeve contacts.
OK.... that would be the sliding sleeve gear cup.
If you'll notice, the gear teeth protruded more than the cup face...... hence my suggestion for the plastic plate.


I will source some plastic for the job if I do it. I could possibly leave the ball bearings and just do the needle rollers.
The caged needle bearings are only active within the gear that is NOT being driven from.

Let's say that you are running a LH prop.
The gear that becomes the "driven" gear will be the lower one. (the upper gear is just along for the ride, so to speak)

The caged needle bearings (within the lower driven gear) will not be providing any friction reduction during FWD propulsion.
In other words, the lower gear, vertical shaft and the caged needle bearings will all be rotating as one.


I'm not suggesting that you NOT replace them...... I'm just saying that they don't take the load that we may assume they do.



If I could of found a more affordable replacement I would of had done it for peace of mind.

Thanks!
You are welcome!
 
Hey Rick,

The main drive gear bearings were replaced under your guidance earlier in this thread, just waiting on some shims to finalise the rolling torque. The whole cone clutch design is pretty interesting and I have spent some time playing with it to see how the arrangement works. I should add to the story that the needle rollers are slightly rusted and cheap to replace so i will do them.

As for the main bearings the upper one has some surface rust ( I have a RH prop so the upper gear is my forward gear ) I assume possibly from condensation as the drive sat for a few years before I bought it and the input shaft seal was leaking on vacuum test. Are you saying that most of the thrust/vertical force on the shafts taken by the bearings in the intermediate housing? A better understanding helps me decide on the critical parts to replace to get the most value for my money so to speak. Where you able to send me the details of the steel keeper you have for sale?

Regards,
Sam
 
............
Hey Rick,

The main drive gear bearings were replaced under your guidance earlier in this thread, just waiting on some shims to finalise the rolling torque.
The whole cone clutch design is pretty interesting and I have spent some time playing with it to see how the arrangement works.
Yes, what a brilliant use of the cone clutch system, of which was around many years before Volvo Penta used it.

I should add to the story that the needle rollers are slightly rusted and cheap to replace so i will do them.

As for the main bearings the upper one has some surface rust ( I have a RH prop so the upper gear is my forward gear ) I assume possibly from condensation as the drive sat for a few years before I bought it and the input shaft seal was leaking on vacuum test.

Are you saying that most of the thrust/vertical force on the shafts taken by the bearings in the intermediate housing?
No..... when using the upper driven gear, there is a downward force against the vertical shaft.
This force is "checked" via the large top LH nut.

The opposing force created by the lower gear unit gear-set is checked/controlled by the tapered roller bearing and it's race at the top of the lower unit's vertical shaft.
This is why shimming is so important when changing a lower gear unit to another Intermediate housing.

The two shafts (transmission vertical shaft and the lower unit vertical shaft) do not share any upwards/downwards force resistance. They are totally separate.


A better understanding helps me decide on the critical parts to replace to get the most value for my money so to speak. Where you able to send me the details of the steel keeper you have for sale?
I have the stress proof split ring keepers for the 270, 275, 280, 285 and Pre-A 290s.
If you want one, you'll need to send my a PM with your phone number.

Regards,
Sam
 
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