Need help with my first OMC

[mycapricess]

I recently bought a 1979 bowings aerocraft boat with a 185 OMC motor and outdrive. I am not new to I/O but all my experence with with mercs. I got the motor running the other day but when i bought it she needed some putting togeather. There are two ports on the exhaust mainfold that do not have any cooling houses running to them. One on the bottom near the back on the motor and the other right on the front end. There is a third that has a house running to it. I am not sure what to do with these other ports. It looks like the prevous owner had them pluged with rubber caps ment for plumbing but they did not hold up. Should i just plug them off and if so with what? Also how do i change the lower gear oil in this machine?

 

[superbenk]

Re: Need help with my first OMC

I'm not following your description of the hoses & manifold issues.

There are 2 plugs on the starboard side of the outdrive's lower unit. One is located just above the anti-cavitation plate & the other is located just under the bulge of the bullet (where the prop shaft runs). To change, pull both plugs, drain fluid, pump new fluid in from the BOTTOM until it's level with the bottom of the upper hole. Put the plugs back in with new nylon washers & you're done.

Remember, the Stringer has 3 oil cavities, so don't just change the lower one. There's an upper gearcase (plugs in the bottom starboard side above the swivel point & at filler at the top as a dip-stick) & intermediate housing (drain under steering gear on port side & fill on port side at the top near where the boot is).

There is a special lube for the lower if you have an electric shift. Hydro-mechanical & full-mechanical can use 80-90 weight outdrive gear lube.

 

[mycapricess]

Re: Need help with my first OMC

thanks for the help on the gear oil. I will have to get that changed once i determine what kind of shift i have.

The mainfolds on the motor have three nipples on each that you could hook a hose up to. One nipple on each has a hose that runs to the thermostat housing. I am assuming the water just exits through the mainfold with the exhaust. That leaves two nipples on each mainfold that i don't know what to do with. I am unsure if there are missing hoses or if i just need to block them off.