Speedo connection point Mercruiser 411 with gen 1 drive

Blentz17

Seaman Apprentice
Joined
Feb 13, 2018
Messages
49
My boat has an old school Mercruiser 488 in it with a first gen outdrive. It’s the one that has the oil plug on the left side. I’m in the process of restoring the boat and when I was tracing the Speedo tube, I noticed that it was cut about half way to the motor.
I have looked everywhere for the speedo connection, there are zero hoses coming from the area of the transom around the exhaust billow where you would normally see the speedo connection. I also don’t see any spot for the plastic connection for the tube.

When looking at the alpha drive I’ve checked the front back and side and don’t see an obvious hole like on the Gen 2s. The Exhaust billow is cracked so I will be pulling the drive to replace it and I was going to take a closer look to see if I could find the connection point.

Does anyone know where the connection point may be or where the tube should exit? I’ve heard in some of the older alpha drives it is inside the lower unit but again I’m not sure. Also does anyone know what the size of the hose is, since it is cut I will have to replace it as well. Any advice would be helpful.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
50,282
You need a separate pitot tube pickup. Kit with pickup and 25 ft of hose is less than $30
 

Blentz17

Seaman Apprentice
Joined
Feb 13, 2018
Messages
49
Ok thanks for the info, the pitot which is on the boat is trash and needs to be replaced anyway, I was not sure if that was the connection point.
 
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