Speedometer Pitot tube

[Mark.24]

Engine: Merc '83, 3 cyl.<br /><br />This might sound daft, but the thing is bugging me. My Clymer book says the speedo pitot tube is next to the gear selector rod. But on inspection there is a plastic nut fixed into the lower unit and then the pitot tube is slid over the nipple of the plastic nut. This rubber tube then hangs in oblivion, or is this an expansion pipe for the gear lube? <br />There looks to be a speedo gauge on the stern, which can be flicked up or down and runs to the speedo. <br />Thanks in advance<br />Mark

 

[Kenny Bush]

Re: Speedometer Pitot tube

That pitot tube opening is a hole drill into the front of the lower gear case. This hole goes through the lower unit and out a small nipple next to the shifter rod(still on the lower unit). A rubber or vinyl hose is attached to the nipple and runs up through the midsection, then the motor and out to the gauge. That is basically it.... A good number of people use the transom mounted pitot tube.

 

[Mark.24]

Re: Speedometer Pitot tube

Cheers Bushcat,<br /><br />So its redundant, glads thats cleared up.<br />So should i seal off the tube?<br />Thanks for your time<br /><br />mark

 

[Kenny Bush]

Re: Speedometer Pitot tube

Just plug it off if you are not going to use the "motor pitot tube". Just plug the nipple end. ..

 

[MrWick]

Re: Speedometer Pitot tube

I had something similiar on my merc but the speedo tube off the engine was still hooked up and the other end was hanging loose under the dash.A speedo pickup was installed on the transom connected to the speedometer.The hole in the lower unit for the speedometer was plugged up,I took a small drill bit cleaned it out and then a longer piece of wire to get futher in,blew with an compressor from the hole in the lower unit all the way up to the end of the loose hose to clear everthing out and now my pickup on the lower unit works like a charm.

 

[Mark.24]

Re: Speedometer Pitot tube

Thanks for that guys <br /><br />Slighty different tac,<br />My engine was manu in Belgium (# 9341608) does anybody know where I can find this on a engine/ year list<br /><br />Mark