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Penta AQ100 Gear Leg

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Hurricaneplanes

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Hi to everyone from accross the pond as this is my first post. I have a Birchwood 25ft cruiser powered with a Volvo Penta AQ105 engine coupled to a Volvo Penta AQ100 Gear Leg. I need to remove the engine and leg from the boat so that I can fit a new transom. The gear leg is off. the cover plate's 6 bolts passing through the transom are off as are the 6 bolts holding the gear shaft plus its housing to the cover plate and then through to the engine bell housing. Now the problem is that I cannot see how to remove this gear shaft housing from the cover plate. I suspect that some corrosion has taken place between the two and I am seeking any advice as how to seperate them please. Would any member have any ideas please or even a workshop manual to either sell or even email the relevant details.
 
I have been able to seperate the engine completely from the drive leg. Not easy but done. If or when anyone has a similar problem pl;ease email me. In the meantime I am still on the lookout for a workshop manual for the AQ100 leg.
 
I may have a manual for the 100. I'll check at my shop and let you know tomorrow. I have'nt seen one of those 100 on a boat in years. I did have one laying in the shop till last year and got tired of tripping over it so it went to the scrapper.
 
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Garry, Many thanks for your reply. If you can find a manual for the AQ100 Gear Leg then I would be most gratefull. Please let me know and I will cover whatever the costs are.
 
For God's sake, put this back together with a 250 or later drive.
The cost to do so will be peanuts compared to finding AQ 100 parts in the future!

You pay for shipping, and I'll donate a 2.15:1 lower unit!
I must have five of them laying around.
They don't wear out, and I can't sell one!

A 250 transom shield is also hard to sell.
You should be able to pick these parts up cheaply!
 
Rick, thank you for your kind offer; however I am halfway through replacing the transom which now has all of the holes cut to refit the AQ100. Luckily I do have a spare AQ100 leg as a standby. Would the 250 leg need a new shield and would the clamping ring whick bolts through the shield onto the bell housing need to be replaced as well?
 
The 100 series and 200 series are like night and day. The only thing the same is the Volvo Penta on it!!! Just checked also, I only have an extra "installation manual" for it, no workshop for the 100, sorry. Need some zinks and a prop nut/washer, I have some of those you can have cheap.
 
The 250 or later drive (the entire drive) would require a 250 or later transom shield.
For a 4 cylinder, there is no need to be concerned about the exhaust relief, as anything earlier than a 225 E or 260 will be using the single relief!

So to answer your question, you could use a 250 shield, a 270 shield, or any 280, 275 using the single exhaust relief.

A 250 or 270 should be a dime a dozen!

.
 
Hurricaneplanes said:
I have been able to seperate the engine completely from the drive leg. Not easy but done. If or when anyone has a similar problem pl;ease email me. In the meantime I am still on the lookout for a workshop manual for the AQ100 leg.
Click to expand...

Hi,

I am having exactly the same problem, except I am planning to refurbish the engine and install it again.

All bolts are removed, and the engine is basically only attached to the drive by the spline drive, supported from below of course. Are there any other options but brute force such as tapping the crank axle, pulling the block repeatedly etc from here?
 
Hi, Rick and others, have posts on " drill a hole in the flywheel cover ", this will let you remove the drive plate from the flywheel, by turning the crank, till you have all the bolts out. From there, it should be easier to take things apart.
Art
 
Hurricaneplanes,
The reason for my suggestion of replacing this with a later engine/drive, is due to the size of the hull..... a 25 footer really needs more power.
Like said, all of these parts should not break the bank, IMO..... especially if you could find a donor boat. And, you'd actually have a better drive system.
There is a universal joint system in the 100 that is all but impossible to find these days, should it fail on you.
The 250 uses components that are much more consistent with the parts that work with the rest of the drives.
Also, it's pretty tough to beat one of the OHC Volvo 4 cylinder engines.

Just a thought!
 
How to separate the engine from the drive shaft

I finally managed to pull it off.

The bolts and starter motor were easy to remove. The locating pins did a good job resisting, but finally gave in to my hammer :)

There are then two things holding the engine to the shaft : The vibration damper which is bolted on the flywheel and the centering bearing which is residing in the end of the crankshaft.

The damper was removed by drilling out the 6 bolts from the engine side. The engine was rotated around the shaft to expose the flywheel, and a drill of 6.5 mm took care of the bolts. The bolt heads came off and landed in the bellhouse. The damper plate could then be drawn from the flywheel from the starter motor opening. At this point the engine could turn independently from the drive shaft.

The final obstacle was the centering bearing, which was stuck on the end of the shaft. To transfer momentum to this bearing it was necessary to insert wedges (screwdrivers) between the engine and the bellhouse. Then a 40 cm shaft was inserted into the 9/16 UNF thread at the end of the crankshaft. A 4 kg steel cylinder was slided on the shaft which had a stop on the end. The shock was enough to pull the drive shaft out of the bearing.

I hope this general description can help other people with their stuck engines!
 
Re: How to separate the engine from the drive shaft

For the guys who are typically having this issue, it is primarily due to water that has gotten between the Flywheel Cover and the Engine.
Water, and not properly greasing the Borg Warner splines and Centering Bearing "pilot nose", has allowed rust to occur.

If you cannot solve the water issue (poor engine hatch seal, poor fishing/crabbing techniques), then put this back together using a sealant between the F/C and aft-most Engine face................ Especially if in salt water!
 
The issue with this engine was not only water in the flywheel cover, but also in the engine cylinders and crankcase due to the carburators acting as rain collectors for some years. The engine cylinders were corroded and cannot be saved (except if the bore is expanded to the B20 measure), but fortunately we have a lot of antique B18 engines lying around at scrapdealers :)

Besides sealing the flywheel cover, I´d suggest installing a drain valve in the bottom. And perhabs a stainless steel tip on the shaft.
 
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