Mercury Outboards - Test Run Evaluation - Lower Unit & Prop

About inboard or outboard motors.

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Retroman
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Location: Great South Bay, Long Island, NY. Building a Zip/Flying Saucer

Mercury Outboards - Test Run Evaluation - Lower Unit & Prop

Post by Retroman » Tue Jan 03, 2012 6:57 pm

Aside from some lower unit and set up issues, the test ride was a success.

http://www.youtube.com/watch?v=Py1QWVVEfmI

Advice and tips are greatly appreciated
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RetroMan
Built A Zip/Flying Saucer. I do my boating on South Oyster Bay, Long Island, NY
Documenting my build on YouTube @ http://www.youtube.com/SuperUnknownMC

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psychobilly
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Location: Tomball, TX

Re: Mercury Outboards - Test Run Evaluation - Lower Unit &

Post by psychobilly » Tue Jan 03, 2012 7:42 pm

Dude if I ever make it to NY I wanna visit two places, ground zero, and the point of no return!!!!!! That looks like my kinda place!

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Wood Nut
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Re: Mercury Outboards - Test Run Evaluation - Lower Unit &

Post by Wood Nut » Tue Jan 03, 2012 10:40 pm

Retroman,

According to the AOMCI.org website the AMC580 is a 10" 10 pitch 3 blade al prop. I don't know about the 22914.
Charlie K.
Building a Flying Saucer

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Roberta
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Re: Mercury Outboards - Test Run Evaluation - Lower Unit &

Post by Roberta » Wed Jan 04, 2012 7:01 am

My Merc manual indicated your 22914A* prop is a 10 3/4" by 12 pitch two blade aluminum prop. The A* indicates A2 for an 11 spline and A1 for 14 splines. Speed range is 30-35mph for a Mark 55.

I had water intrusion issues with my Merc 500 lower unit. Turns out the driveshaft was rusted and pitted where it went through the seals that prevent water from getting into the lower unit from the pump and to keep the oil from escaping out the water pump. I found a NOS shaft on Ebay and replaced it and resealed the lower unit.

Here is a link to East Coast Marine. They have repair and parts manuals for your motor if you need them. My manual does not have any repair info for your motor.

http://store.oldmercs.com/category_s/117.htm

Roberta :D
Roberta "Queen of the Boat Builders"
Built Zip "Oliver IV", Super Spartan "Jimmy 70", and Torpedo "The Glen L".

Retroman
Posts: 199
Joined: Mon Apr 25, 2011 5:08 am
Location: Great South Bay, Long Island, NY. Building a Zip/Flying Saucer

Re: Mercury Outboards - Test Run Evaluation - Lower Unit &

Post by Retroman » Thu Jan 05, 2012 4:52 am

thanks a bunch for the info
RetroMan
Built A Zip/Flying Saucer. I do my boating on South Oyster Bay, Long Island, NY
Documenting my build on YouTube @ http://www.youtube.com/SuperUnknownMC

Retroman
Posts: 199
Joined: Mon Apr 25, 2011 5:08 am
Location: Great South Bay, Long Island, NY. Building a Zip/Flying Saucer

Re: Mercury Outboards - Test Run Evaluation - Lower Unit &

Post by Retroman » Fri Jan 06, 2012 8:28 pm

thanks guys, very valuable insight from all of you, I ordered the seal, should be here in a few days. It's gonna be 50+ degrees tomorrow, so you know Im going for a ride. I ran a kiekhaefer 10 3/4" 12 pitch, 2 blade prop last week, and did 48kmh/30mph. This week I gonna run a Michigan wheel 10", 10 pitch, 3 blade prop. I think Im gonna get more top end despite the smaller diameter. I'm also gonna try not, filling the lower unit to the brim. It seems from what you guys said, that the seal might have been put in backwards intensionally, to ride on a better part of the prop shaft.

I've been dealing with hydrallics for 25 years in the automotive lift field, both above ground, approx. 2000 psi, and inground lifts, approx 800psi. In my opinion, the seals are design to work a certain way, and should be installed in the correct direction. I have no idea how much pressure is actually generated by a churning lower unit, maybe 5 lbs or so, but I can see how the oil would escape if the seal was installed upside down. As far as the water is getting in the lower unit, Im not sure.
It could be the seal under the pump, but I doubt it, based on the 1 hour meeting I had with the previous owner when I bought the motor. Click on link to see video:
http://www.youtube.com/watch?v=dEkosiHZdD4
I have no experience with outboard lower units, but Im sure there is a high pressure, low pressure situation created by the spinning prop, and water, and thrust created, and Im sure that it has an effect on the performance of the seal. That pressure situation might be sucking water past an incorrectly installed seal at high speed.

Food for thought. When the seall gets here, i'll install it correctly and inspect the shaft. Thanks for the input.
Jim
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RetroMan
Built A Zip/Flying Saucer. I do my boating on South Oyster Bay, Long Island, NY
Documenting my build on YouTube @ http://www.youtube.com/SuperUnknownMC

upspirate

Re: Mercury Outboards - Test Run Evaluation - Lower Unit &

Post by upspirate » Fri Jan 06, 2012 9:37 pm

My old Mercury mechanic that I use says that you can't get the proper lower unit grease now days.

He says this is close and the stuff to use in these old 1950's Mercs,and not to use the new stuff.

http://store.oldmercs.com/product_p/92-24734-1.htm

It's heavier than the new stuff, and you might not have problems leaking....at least as much.

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