reverse lock hooks bent shut, connecting rod pulls out freely? '79 mercury 500. 50hp

joeboater7

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Joined
Apr 23, 2012
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27
I am brand new to this message board. I just recently purchased a '79 glastron hp154 bass boat with a mecury thunderbolt 500 50hp outboard (for $850). From browsing the message board you all seem very helpful and friendly, so thanks in advance for any advice you might give!

I noticed my reverse lock hooks were not engaging the trim/lock bar properly, even though they move as they should when I shift when the motor is held up. Closer inspection revealed the right hook was pinched shut a bit too much so that the hook wouldn't fit over the trim/lock bar.

I removed the spring, a few cotter pins, and slid the hook assembly off the motor.

Now here's where I am stuck. I have two questions:

1) How should I go about spreading the right hook open a bit more? It seems pretty solid and I just don't know how I might go about applying enough force to open it. Any suggestions?

2) I noticed the extension arm that comes out of the lower unit that controls the hook position is not attached in anyway into the lower unit. It pulls right out. After three or four minutes of blindly trying to find where it belongs in the lower unit, I did find what feels like a sleeve or seat that the extension rod slides into and seems to fit quite perfectly. When I shift it does move the extension rod. So I think I have it it the right location. It just seems odd to me that it is not fastened in any way to the lower unit. Is this normal?

Thanks a ton for your help!
 

carholme

Rear Admiral
Joined
Sep 4, 2010
Messages
4,845
Re: reverse lock hooks bent shut, connecting rod pulls out freely? '79 mercury 500. 5

If you are sure it is a 1979 engine, (do you have the s/n?) then yes you are right about the rod. It does fit into a guide, item 12 in this link:

http://www.crowleymarine.com/mercury-outboard/parts/474_16.cfm

and then the end of the rod rests on the sliding surface of the cam, item 43 in this link:

http://www.crowleymarine.com/mercury-outboard/parts/474_19.cfm

Scroll down to the small picture of the cam and click on it to blow it up and you will see the sliding surface on the side of it. When reverse gear is selected, the rod is pushed up on that sliding surface causing the pawls to lock.

For the other question, are you saying that when reverse is selected, you can or cannot lift the engine up?

Gerry
 

joeboater7

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Joined
Apr 23, 2012
Messages
27
Re: reverse lock hooks bent shut, connecting rod pulls out freely? '79 mercury 500. 5

Thanks for the diagram. That looks accurate.

Part #7 on the first diagram is the part that just slides out. Am I right to assume it is supposed to be loose like that? I can't tell from the diagram if it is supposed to pull out freely when the upper end of the rod is disconnected..

My second question was how to spread open the hooks/pawls(?) The previous owner must have slammed down the motor when the pawls were shut causing them to compress to a smaller size. The problem was that the pawls were too tight to go over the trim bar. Or if i forced them on, they were too tight to release when in forward. I removed the pawl/hook part and put the hook openings on a corner of metal and used a hammer on the back side. This caused the hooks to open wider. they now seem to be the right size. So that part is solved.

So, my only remaining questions, is: should Part #7 on the first diagram freely pull out when disconected from the pawls?

Thanks a ton!
 

carholme

Rear Admiral
Joined
Sep 4, 2010
Messages
4,845
Re: reverse lock hooks bent shut, connecting rod pulls out freely? '79 mercury 500. 5

Yes, item 7 should be free to remove when disconnected.

Gerry
 
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