Volvo Penta AQ130A / 100 outdrive slips out of gear

1970PM1700

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Hi, all!

I just picked up an immaculate 1970 Pere Marquette 1700 with a Volvo Penta AQ130A engine and Model 100 outdrive. The thing runs like a champ, but on my second trip out I had 5 people in the boat and while pushing it up to cruising speed (4500-4700 RPM) the engine suddenly unloaded and revved up to about 5500. My first though was the shear pin, but it was fine. If I putter around at or below 2500 RPM it works fine, but if I put a heavy load on it, such as advancing the throttle quickly or trying to reach cruising speed it will seem to pop out of gear. Any thoughts on what this could be? I've tried researching the problem, but all I've found is how reliable these things supposedly are.

The thing has not lived a rough life- it's had one owner and has spent its life in fresh water in Minnesota where it was stored for 8 months out of the year and most years of its life it wasn't even taken out. The engine and outdrive still gleam with their original paint and both are clean enough to eat off of. The 90w in the drive still looks brand new, but no telling when it was changed last...

Please help!
 

UpperUpsilon

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May 20, 2009
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Re: Volvo Penta AQ130A / 100 outdrive slips out of gear

Sounds like a spun prop hub. Mark the hub and prop, and then get it to 'slip' again in the water. If the marks no longer line up, your hub is spun, and can be repaired fairly cheaply.
 

1970PM1700

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Re: Volvo Penta AQ130A / 100 outdrive slips out of gear

Sounds like a spun prop hub. Mark the hub and prop, and then get it to 'slip' again in the water. If the marks no longer line up, your hub is spun, and can be repaired fairly cheaply.

That's not the case. I pulled the lower gears this afternoon and everything looked perfect with no sign of wear on any of the components and not a trace of metal in the oil or in the bottom of the drive.

Any more ideas?
 

captmello

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Re: Volvo Penta AQ130A / 100 outdrive slips out of gear

what about the spun prop? Did you check it? Thats what it sounds like. Did you try another prop?
 

UpperUpsilon

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Re: Volvo Penta AQ130A / 100 outdrive slips out of gear

Well, this is a problem with the actual propeller hub... like the part of the prop with the splines in it that mates with outer propeller housing.

Here are some other possibilities:

http://www.mercstuff.com/spunprop.htm
 

Don S

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Re: Volvo Penta AQ130A / 100 outdrive slips out of gear

A Volvo drive is NOT a Mercruiser drive, posting information frome Mercstuff isn't going to help because they are completely different systems.
1970, you could have had water in your drive, the shift mechanism not going all the way into gear. You don't have a coupler, so forget that.

Most common cause for your problem. Faulty prop hub. NOT lower drive unit gears. Just the Prop.
 

muc

"Retired" Association of Marine Technicians...
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Re: Volvo Penta AQ130A / 100 outdrive slips out of gear

Also might want to put the right gear lube (motor oil) in it.
Good Luck Muc
 

1970PM1700

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Re: Volvo Penta AQ130A / 100 outdrive slips out of gear

A Volvo drive is NOT a Mercruiser drive, posting information frome Mercstuff isn't going to help because they are completely different systems.
1970, you could have had water in your drive, the shift mechanism not going all the way into gear. You don't have a coupler, so forget that.

Most common cause for your problem. Faulty prop hub. NOT lower drive unit gears. Just the Prop.

I am pretty certain it's not a spun prop. The prop is held to the shaft only by a 5/16"-ish shear pin that is not sheared. I'm guessing it has to do with the shift mechanism, but I adjusted the linkages to give the firmest possible engagement into gear and there is no change in the way it behaves. It probably got a little water in it at some point since the stuff I drained out had a slight milky texture.

As for filling it with the right oil, I filled it with 90w, just like the owner's manual says to do- not motor oil. Is swapping to motor oil recommended for some reason?

It figures... I've been an auto mechanic my whole life and an aircraft mechanic for 3 years. I know nothing about boats, but ANY other part of the boat would have failed I'd already be back out on the water. This thing's got me stumped out of sheer ignorance.
 

Don S

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Re: Volvo Penta AQ130A / 100 outdrive slips out of gear

I am pretty certain it's not a spun prop. The prop is held to the shaft only by a 5/16"-ish shear pin that is not sheared.

Dude, you are not listening. Even a prop with a shear pin can have a rubber hub in the prop.
Remove the prop and take it to a prop shop or send it to one and have it checked out. You could do it your self on the boat, but I'm not sure you would listen to the logic in how to do the test.

Having said that, if you have a 100 and not a 100B, then it should have 90W gear lube. Some of the Merc and OMC and newer Volvo posters may not know that however, use what your manual says. It's worked this long.
 

Fun Times

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Re: Volvo Penta AQ130A / 100 outdrive slips out of gear

When you changed the drive oil How did you fill it up exaktly? When you reujusted the shift cable at the drive Did you pull off or play with the shifting mecinizum that is bolted to the upper drive unit housing where the shift cable would hook up to it with the brass fitting coming from the cable itself at ALL??? Next why are you 100% sure it is not the prop hub??? Have you pulled the prop off and looked at it??? By the way some times just looking at it still will not tell you if it is spun or not.:eek: sorry about the bad spelling I'm not the gratest speller and I don't fell like looking it up right now:p
 

1970PM1700

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Re: Volvo Penta AQ130A / 100 outdrive slips out of gear

Dude, you are not listening. Even a prop with a shear pin can have a rubber hub in the prop.
Remove the prop and take it to a prop shop or send it to one and have it checked out. You could do it your self on the boat, but I'm not sure you would listen to the logic in how to do the test.

Okay, I have the prop sitting in my lap as I type this and I must say that I indeed deserved that... I see now what you are talking about- I just ***-u-me'd that the prop was a single cast piece of metal.

I will investigate further, but I can look at it and it looks as though it has spun.

I will proudly wear my dunce cap as I go out in public today.
 

1970PM1700

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Joined
Jun 10, 2009
Messages
21
Re: Volvo Penta AQ130A / 100 outdrive slips out of gear

Sounds like a spun prop hub. Mark the hub and prop, and then get it to 'slip' again in the water. If the marks no longer line up, your hub is spun, and can be repaired fairly cheaply.

what about the spun prop? Did you check it? Thats what it sounds like. Did you try another prop?

Most common cause for your problem. Faulty prop hub. NOT lower drive unit gears. Just the Prop.

Yep...

I'm still young and stubborn. I should really learn to listen to suggestions when I'm asking for them! Especially when I admit to not knowing what I'm talking about and y'all actually do!

My sincere apologies and thanks for the patience and help- my boat is back to 100%again... and I feel like an idiot...
 

Harrydenbreejen

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Apr 30, 2012
Messages
2
Re: Volvo Penta AQ130A / 100 outdrive slips out of gear

I have a late 1960s 100 leg and have a lube comment: 15 years ago I was having issues engaging when I shifted into gear. Like you I was using 90W leg oil, but also I had some infiltration of CV joint grease from my home made drive coupling which was made using two VW CV joints. I finally found an older retired X-Volvo/penta shop owner who knew the 100 series leg. The leg pumps it's leg oil up to the drive coupling "zappa joint" and it drains back into the leg. My gear engagement issues were solved when I flushed the leg out a few times and used his reccommendation of straight 30w oil. It's been running great like this since. Its pushing my old housebout arround Shuswap Lake B.C. My prop is only shear pinned, not splined, no rubber, beat_up and I'm looking for a new one. .... regards, Harry
 

Harrydenbreejen

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Re: Volvo Penta AQ130A / 100 outdrive slips out of gear

oops I see this is a three year old chat. I'll get the hang of this e-gabbing eventually
 
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