AQ290-DP Drive Shaft Rebuild - Bearing/Seal Info?

Jersey13

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Hi all. Looking for some info/recommendations. Working on my Unc's boat with a AQ290-DP Volvo Penta outdrive mated to a Marine Power 5.7 GM. We're rebuilding the main shaft since the bearings are shot. The shaft is splined 26 on the input, 10 output and the flywheel cover is stamped 835978. This cover does have the zerk fitting to grease between the bearings and the bearings that came out are sealed on the outside and open to the inside.

I've read a few conflicting posts on which bearings to rebuild this with - sealed or open? I'd appreciate any info on which way is best to go in terms of strength and longevity. Also, if you happen to have the part #'s for both the bearings and seals you're suggesting and a good source, that would be much appreciated as well!

Thanks for all the knowledge.

- Jersey
 

Don S

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Re: AQ290-DP Drive Shaft Rebuild - Bearing/Seal Info?

I can understand using sealed bearings if you have no way of greasing them, but since you do, why use sealed. If you are just reading threads about bearings, some of those housing don't have an option to grease the bearing. You have to compare apples to apples in your searches.

It's up to you which you want to use.
 

Jersey13

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Re: AQ290-DP Drive Shaft Rebuild - Bearing/Seal Info?

Thanks Don. I was just wondering if one was better to use than the other. My thought process was, IF the sealed bearings were just as durable, why not use them and take something off the list to do repeatedly? As i get older, i seem to be looking more toward a "maintainance free" lifestyle. LOL.

I just spoke with my Uncle and he ordered everything through this site earlier today. Appreciate all your help over the years.

- Jersey
 

Don S

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Re: AQ290-DP Drive Shaft Rebuild - Bearing/Seal Info?

Sealed bearings does not make them maintenance free, it just makes it impossible to do any preventive maintenance, so you have to replace parts instead of pumping in new grease.
 

Jersey13

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Re: AQ290-DP Drive Shaft Rebuild - Bearing/Seal Info?

Gotchya. Again, thank you Don.

- Jersey
 

Jersey13

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Re: AQ290-DP Drive Shaft Rebuild - Bearing/Seal Info?

Quick question - would you recommend using marine grade grease or just plain ol' wheel bearing grease for this application? As i understand it, marine grade is more water resistant and wheel bearing grease is better at handling loads, correct? Again, thanks.

- Jersey
 

Don S

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Re: AQ290-DP Drive Shaft Rebuild - Bearing/Seal Info?

There better not be any water in that area. If there is, you have a lot of other things to worry about as well.
Keep good bellows on it and you shouldn't need to worry about it. They are also very easy to replace.
For boats kept in the water, the bellows should be replaced every other year.. I did mine yearly, but I had the 2 bearing housing and had to pull the engine to replace the bearings.

http://forums.iboats.com/mercruiser...tdrives/outdrive-side-pin-removal-309095.html
 

Jersey13

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Re: AQ290-DP Drive Shaft Rebuild - Bearing/Seal Info?

Thanks Don. Wheel bearing grease it is.

- Jersey
 

jerryjerry05

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Re: AQ290-DP Drive Shaft Rebuild - Bearing/Seal Info?

You'll want to use the open bearings since your flywheel cover has the grease fitting on it.
6206 rear bearing... 6007 front bearing in a good quality brand.
Seals are 35x62x7mm rubber encapsulated and single lip if you can find them.
Look at the Timken and TCM brands.

Install the new bearings and install the PDS back in the housing dry.
Pre-fill the grease cavity before you install the seals.
Turn the PDS as you pre-fill to get the air out.
Stop when you see grease come through the bearings.
Glue or stake the forward seal so that it can't be pushed out with grease gun pressure.
Install the rear seal with the lip and tension spring facing the rear.
Grease these with the engine running in the future. 3 to 4 pumps.

Don is right...... if you grease these at the right interval, they will last another 15 years or more.
With sealed bearings, they won't go quite as long.

Don is also right about water in there. If you find water in this area, you have bigger problems.

The green marine grease won't be my first choice. I would use a high pressure bearing grease, and what ever you start with keep using the same grease.
 

Jersey13

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Re: AQ290-DP Drive Shaft Rebuild - Bearing/Seal Info?

Thanks Jerry. Appreciate all the great info and knowledge.

- Jersey
 

Jersey13

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Re: AQ290-DP Drive Shaft Rebuild - Bearing/Seal Info?

Jerry - after reading your post again, you mentioned "Install the rear seal with the lip and tension spring facing the rear"

Did you mean the facing the rear of the motor or rear of the boat, toward the transom? Both seals came out with the spring side facing each other, up against each of the bearings.

Thanks - Jersey
 

jerryjerry05

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Re: AQ290-DP Drive Shaft Rebuild - Bearing/Seal Info?

When done, both seals will be installed in the same direction with the lip and tension spring aiming towards the rear.
The front seal works hydraulically to prevent the grease from escaping.
We want the rear seal to bleed off any over pressure. It's not a water seal.
Some will even clip the lip so it can't completely seal because you don't want to loose the front seal.
 

Jersey13

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Re: AQ290-DP Drive Shaft Rebuild - Bearing/Seal Info?

Thanks Jerry. I would've never thought the real seal would act as a pressure release but now makes sense. Appreciate the knowledge once again. Learn something new every day.

Would you have any suggestions on prop sizing? I make a post a few days back in that section without much action.

http://forums.iboats.com/prop-quest...n-290dp-25-cat-limbo-vortec-350-a-604223.html

- Jersey
 

Jersey13

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Mar 18, 2001
Messages
101
Re: AQ290-DP Drive Shaft Rebuild - Bearing/Seal Info?

Just a quick thanks to you guys again for the help. Everything reassembled, motor back in and outdrive back on. Not in the water yet but it all sounded good running on trailer. Thanks.

- Jersey
 
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