Vibration AQ280.

Ok, this is my first boat so I am kinda fumbling my way through the repairs. My boat is an '83 Galaxy 19' b/r. It has the AQ225d/AQ280. I took delivery of the boat first weekend in november, and thanks to the mild weather we had in pa in november, i was able to take her out for a ride. While underway, i noticed a vibration. I assumed it would be u-joints. Well, a month later, i finally had the time to pull the outdrive. I was expecting a nasty rusty blob that were to be the u-joints, only to find very clean u-joints, that move smoothly with no notchiness. There was no water in the bellow, but there was some gear oil in the bellow. I inspected the splined shaft, and tried to wiggle it. There was no play what so ever. I did a search here for vibration, and came up with nothing that applies to me, hence my post. Another question i have is: Is the AQ225D a 305 or 307. I cant seem to find the answer in my seloc manual. Just a curiouocity thing.

Re: Vibration AQ280.

its a 305.

Maybe yoyu have a bent prop causing the vibration.

oil in the bellows is not good. It typically means the seal has failed in the upper gear box. running this way can be bad if you run the outdrive low on oil. Unfortunatly, resealing the upper gear box is not a diy project imo. Call around to find someone who knows how to work on the old VP outdrives and get an estimate. I think you should be able to get the upper resealed for under $500.

good luck!

Re: Vibration AQ280.

Find yourself an OEM manual, and toss the Seloc, or use it for pictures only along with the OEM.

The 225 will be the SBC 5.0L engine.

The bearing crosses can feel smooth to the touch, but may not be OK.
You would need to actually take them apart to fully examine them. If you do that, you may as well replace them.
In this year range, and if no one has changed out the universal shaft, the Spicer 5-1306X is a great replacement cross.
The grease fitting is in the apex of the cross.


If the universal shaft is good, the vibration is probably due to bad PDS bearings [primary drive shaft].
If it has the origingal red 1 pc flywheel cover, the engine must be removed in order to remove the PDS and to replace the two bearings.
These will be an open 6206 and 6007 and two 35x62x7mm rubber encapsulated seals.

Re: Vibration AQ280.

The only ways to know for sure if you have an upper gearbox seal leaking is to pressure test the drive. The pressure test is not that difficult and gives quite a bit of peace of mind to know for sure what's going on.

Re: Vibration AQ280.

Ok, I am a school bus mechanic, so I am confident of my abilities. What is the deal with the upper gear box reseal. For $500, oil is much cheaper, and there wasn't THAT much oil in the boot. As for the PDS, there seams to be absolutely no play (wiggle), and no signs of rust or bluing caused by heat. Really don't want to pull the motor at this time. The prop seems like the most logical thing to check next. The ujoints, if I were looking at joints in a car or truck, I would say they are very good, almost new. I appreciate everyones input. I just need to know what is difficult about changing the upper gear box seal. Thanks again everyone!

Re: Vibration AQ280.

I agree that a bent prop shaft may be the problem. Sure worth checking into.

Copied from another source.

Since the heaviest loads on these is during planing speeds (drive universal shaft fairly straight), marine out drive bearing crosses (aka u-joints) do not articulate to the degree that our car/truck crosses do, so the needles tend to bear on a concentrated location of the trunion.
They eventually wear into the trunion forming a groove, whereas the automotive unit needles are rolling across the trunion as they articulate.
This creates the need for more frequent replacement than that of our automotive counter parts of which are designed for more articulation.
While they may feel good, this wear pattern cannot be easily felt or detected until disassembled and physically inspected.
By then, we may as well replace them.


PDS bearings are very difficult to assess while still installed. I know of no fool proof means to determine if they are good!
It does not take much play in order to create a vibration.
If left unattended and when/if they fail, the damage may be very costly.
A failure here will often take out the snout of the flywheel cover, and in some cases, will take out the BB clamping collar.
A good used V-8 1 pc Flywheel Cover is about $400 or so.
A front clamping collar is approx $380-400, and must be shimmed correctly to the gear case.

Re: Vibration AQ280.

Well, I guess its looking like I am pulling the motor to do this right. At least its an easy one to pull. I was hoping to not do that quite yet. Have only had the boat in the water once for a half an hour, and now I am damn near rebuilding it. At least that's what it seems like. And I just put the boat in storage and can't get it until april. My idea was to fix up the outdrive, then slap it on in the spring. Where can I get the alignment tool for reassembly. Thanks again!

Re: Vibration AQ280.

Why are you pulling the motor? If your ujoints look good and your pds bearings are tight, why are you going after those?

You need to trouble shoot this some more.

Oil is cheaper than the $500, but a replacement outdrive could cost a lot more.

The trick to rebuilding the upper is shimming and setting up the bearing pre load. Its in the manual, in the adults only section.

BTW, you don't need an alignment bar.

Re: Vibration AQ280.

Captmello, this is a 1983 boat with a V/P AQ225D/280. If the PDS bearings have only been replaced once, he is probably overdue now.

$500 compared to the cost of a flywheel cover, and possible clamping collar, is pretty much peanuts.


BlueLightSpecial, that is true, you do not need any alignment tool for this drive. Once after initial installation, it is fixed.
If you pull the engine with the mounts attached [pull the lag bolts only], and leave the f/c in place, you won't have to replace a rubber cushion/sealing ring and you won't need to reset the engine mounts.
The PDS can be removed while the flywheel cover is still attached to the shield.
You also need to remove the transmission only for this work.

Re: Vibration AQ280.

The issue of an oil leak isn't the loss of oil. When the drive heats up during use, there is a slight pressure in the housing. When the drive cools, and the pressure is reduced, it may suck water back into the leaking seal. If that seal happens to be the forward gearbox seal and the bellows develops a leak, water could be sucked into the drive from that location. The fact that there is oil in the bellows points toward a likelyhood of a seal leak. It's really more about routine maintenance and resolving small problems as they become revealed so that they don't turn into bigger and more expensive ones.

Oil in the bellows may or may not have anything to do with the vibration problem. It could be excess grease from the u-joints, it could be excess grease pushing out from the drive shaft bearing area, or it may be drive oil from a leaking front seal. Finding and fixing that issue may or may not do anything at all for the vibration but at least you're one step closer to letting the outdrive live longer.

Re: Vibration AQ280.

I understand the leaking seal issue, just like an axle with a plugged breather. Pressure will build and the weak seal will leak. What I am getting at this: I need to prioritize the repairs. The upper gear box is easy enought to pull, but keeping an eye on it, I can hold off a little bit. This isn't a repair that I have to do "while you're in there". But the PDS bearings and the ujoints I might as well do. I could even wait on the ujoints for that matter. I am not trying to cheap out, I just can't do it all at one time. The plus to pulling the motor is being able to check out the freeze plugs, in case any are rotted, and clean up some wiring. Not that its a wiring nightmare, just needs routed in an organized way. I do have two other 280 o/d for parts, should the worst happen to the gear box, but that doesn't mean I am going to wait for that to happen. My next question is how does the shaft come out with out removing the f/c? Thanks again for everyones input, it is much appreciated!

Re: Vibration AQ280.

BlueLightSpecial said:

My next question is how does the shaft come out with out removing the f/c? Thanks again for everyones input, it is much appreciated!

Click to expand...

You'd separate the engine at the rear flange leaving the f/c attached to the transom shield. This way you don't mess with the rear rubber cushions and clamping ring.
http://www.marinepartseurope.com/PentaPictures500/10972.jpg

You'll have access to the front of the pds so it can be driven out the rear once the 2 snap rings are out of the way.
Front bearing stays in place until the pds is out.
Reinstall in reverse order.
It's been recommended to glue the front seal in place and pre-fill grease area before the rear seal goes in.
Also the 2 brgs are available in a sealed version. we want open brgs for the 2 brg pds.


I've earmarked some pictures in the past.

You probably have the original Volvo Penta red flywheel cover that uses the 2 brg pds.
It will have a grease fitting down low behind the engine [# 73].
http://www.volvopentastore.com/mall/image/vendor/699/EPC/bigger/8067_big.png
If so the engine needs to be pulled for pds removal.

If it has been replaced with a later one, it may be the 1 brg pds flywheel cover.
The V-8 1 brg f/c does not have the grease fitting [sealed bearing].
The pds should come out the rear of this one like the OHC 4s.
http://www.volvopentashop.com/Catalogs/PentaParts/7797016/12121.png
If so the engine may not need to be pulled. It's worth a shot.


Here is a view of a 2 brg pds showing where the bearings and seals sit.
If you do have the later 1 brg pds f/c it will be a sealed bearing like mine and with a pilot nose.

Either one will have the two large snap rings that need to be removed with a long needle nose plyers.
The tips get modified to fit the snap rings eyes.

Re: Vibration AQ280.

I have to say, you guys are awesome! Thank you for putting up with my crankiness, and answering my questions! I think I will be pulling the motor after the new year. I will feel better going down the river this summer, now knowing how the bearings and u joint are, and not worrying "what if?" I guess I am doing it more for peace of mind. I plan on installing new bellows, and keeping a close eye on the top gear box until the end of the season, or unless the leak gets wose. Thanks again e every one for all your info. I will keep you guys posted

Josh