Re: 1975 EVINRUDE 115HP
Some of the posters are confusing your 1973-77 V4lower unit with the later models. <br /><br />On yours, there is a fitting on the top of the shift rod, that is captured by a pin in the pivoting mechanism under the carbs. If you loosen/remove the main bolt that holding the pivoting mechanism together, the pin lets the fitting go. Most people find it easier to remove the carbs (maybe cleaning the carbs out at the same time), than trying to futz around ounder them. <br /><br />On the later models, there's a nice arrangement on the port side that you can get at, to free the shift shaft, without pulling the carbs. Also oin the later models, there is no fitting at the top of the shift shaft, just a flat on the shaft with a hole in it. Finally, on the later models, which are purely mechanical, the length of the shift shaft is important. On your lower unit (which is hydraulically-assisted mechanical), try not to change the length of the shift shaft , but it's not critical. If it got threaded around some, turn it until the shaft if just flush with the top of the fitting (not sticking through any) that should be just about right. Again, it is not critical on yours, but is on the later models. The 21" etc measure does not apply to your lower unit, at all.<br /><br />I wouldn't run in salt much with a leaky lower unit. Not a good idea anyway, but yours has a hydraulic pump and valves in it - salt water is not kind to them. Ezeke's pressure test works well, keep it under 7psi, hopefully it's just a drain plug gasket, but at least you'll know where it's leaking.