OMC 305

Could someone explain to me ho

Could someone explain to me how the engine coupler helps the water flow to the engine.......trying so hard not to give up..........Thank you in advance for your time and patience.

Cathy....as you already know &

Cathy....as you already know (too well) the drive water pump impeller sits at the top rear of the drive. The shaft that turns is actually an extension of the u-joint drive shaft. This shaft is turned by the engine coupler. It's a splined fitting mounted in a rubber mount. The splined end of the u-joint shaft fits right into it. If the coupler was shot then what would happen besides you not going anywhere is that the impeller would not be turning either so you wouldn't have any water flow from the pump. Classic symptoms of a coupler going while you are driving the boat is first of all a burning rubber smell followed by little black bits of rubber falling into the rear of the bilge and then overheating because the water pump isn't turning anymore.

"Cathy- do you have an origina

"Cathy- do you have an original omc repair manual? I have been trying to upload the cooling system problem checkpoint pages and diagram from the manual but having problems uploading on this site. If you have an original manual it has a troubleshooting section that will explain all possible cooling problems, an exploded view of an outdrive and an exploded view of cooling componets by engine type. I scanned all this to post but have not had any luck uploading it. I am assuming you have a cobra not a stringer outdrive?"

"yes I have a Cobra not a stri

"yes I have a Cobra not a stringer, and we do have a manual. I have one other question. Does anyone know which direction the drive shaft should be turning and does this influance the direction of the fins on the impeller. Thank you as usual for you time"

"If you look in your service m

"If you look in your service manual under cooling system; water flow diagram: vertical drive and transom mount,all models on page 5-8 the exploded view of the lower unit shows the rotation of the impeller (two little arrows). The rotation of the impeller (looking at the back of the unit) is clockwise. The impeller fins should be slightly bent to the right of center when installing. Use a little marine grease in housing when installing new impeller so it has some lubrication on first start up. Be sure the small vent hole is clear so impeller will prime."