1/8 inch hole in back of lower unit on Yamaha 115

[lexkyboater]

It's a 93 model, if that matters, but the guy I bought it from says that the 1/8 inch hole just above the gearcase in the lower unit is for the speedometer gauge. I checked lower unit oil after we ran it 10 minutes in a lake and it's clear w/o any water in it. The hole in the lower unit is clogged up so he says speedometer doesn't work. It doesn't have one of the old-style water pick up tubes installed on the boat. If this is a water pick up inlet, and it's clogged, can I stick something in the hole to unclog it? I ordered the Seloc manual for this motor today too. The motor is on an 83 Cheetah. Thanks for any info, Steve

 

[WillyBWright]

Re: 1/8 inch hole in back of lower unit on Yamaha 115

A paperclip might work. Back-blowing with compressed air in the speedometer hose might work. If it's bad enough, a tiny drillbit is a last resort. Just be careful not to drill metal. It goes in about 1/2".

 

[JUSTINTIME]

Re: 1/8 inch hole in back of lower unit on Yamaha 115

compressed air is the best
even the caned air works

 

[lexkyboater]

Re: 1/8 inch hole in back of lower unit on Yamaha 115

Finally got around to checking on this. 110 psi on my air compressor didn't do it, even after several attempts, so I ended up working a small drill bit and a bent fishing hook with the point dulled in there, and it ended up being about 1 full inch deep. I could tell when I reached the end because I felt/heard a metal sound. After about an hour working with it, finally got it to blow out.