speedometer on mariner outboard

posted May 06, 2006 12:42 PM <br />--------------------------------------------------------------------------------<br />I recently purchased a boat with a 90hp mariner outboard. I am not sure of the year of the engine, however I do know the boat is a 79. If I had to guess I would say that the engine is not the original.(looks to be maybe mid to late 80's. My question is this.. The boat has a speedometer and all apears to be hooked up except for a thin black tube which runs to the back of the boat then just stops there(it looks like maybe it was just cut off there. What is this hose and where does it go hooked up. when I blow on the hose the speedometer does move slightly. Thank you for any help on this.<br /><br />--------------------<br />JV

Re: speedometer on mariner outboard

Speedometers on most boats are "pitot" driven. This is a separate plastic deal attached to the back of the boat that sticks into the water. Water pressure as the boat moves compresses air in the tube proporational to its speed and that's what moves the needle. Check the stern near the bottom. If the pitot is gone you can buy a new one right here on iBoats or at any department store that sells boating stuff. They are just a couple of bucks. Your engine may even a pitot built into it but since we have no idea what year it is I can't be of any help.

Re: speedometer on mariner outboard

Thanks for the advice. I will check the stern for that pilot. If it's not there I will just go ahead and buy it right here. As for the year of the outboard. Is there any way of finding that out? Would it be somewhere on the engine itself? Again thanks for your help.

Re: speedometer on mariner outboard

If the tube will not reach the engine regardless it is not ment for the engine. what may have happend is your boat may have had a engine with a built on speed presure gauge, but sens the engine has been replaced Im sure they just disconected it and left it. I think you have a hull mounted gauge myself. Like up in smoke suggested check, than buy according to what you find. If needed you can pick up a new dash gauge and assbly for under $30 online if you shop around. Not hard. Good Luck

Re: speedometer on mariner outboard

Look for the serial number on your engine. There are several sites that you can use to cross-reference the number to find the year model of your outboard. Also, there are many very helpful people on this site that will tell you the year if you post the number.

Re: speedometer on mariner outboard

Thanks for all the help guys. The tube does not reach to outboard so I just went with the suggestion of buying a pilot. As for the year of the engine I am going to get the serial number and post it, hopefully someone will be able to tell me the year. It would be nice to know for future reference on buying replacement parts. Thanks again guys this site is awesome..