No water flow from stern drive to engine

[GRANBATEAU]

Hello:
I have a 1978 Cruisers Yachts Gran Bateau. It has a 283 ci 225 HP engine and an OMC sterndrive. I wanted to make sure the engine runs while the boat is on the trailer. I attached a pair of muffs to the water inlet on the lower gearcase and removed the water hose from the bottom of the antifreeze cooling unit to be sure there is water flow from the lower gear case to the engine. This hose comes directly from the top on the intermediate gear case. When I turn the engine over, there is no water flow whatsoever from the opened end of the hose. I just finished rebuilding the water pump in the upper unit . There was no water flow before the rebuild either. When I remove the 2 small covers, one on each side of the upper gear case and pour water into the opened end of the hose, some water comes out of the hole at the top of the area underneath the covers I removed. Does the water pump need primed for it to pump water? I assumed that the water pressure from the garden hose to the muffs would supply water to let the pump begin pumping. Any help or thoughts would be greatly appreciated. Thanks so much.

 

[GRANBATEAU]

Some additional information on this item. I removed the bottom gear case from the top gear case and connected the water muffs to the water inlet area on the bottom gear case. When the water is turned on. water comes up through the bearing/driveshaft area in the center instead of where I thought it should go which is around the outside of that center area. Lastly, does anyone know how I can separate the 2 halves of the bottom drive case?
I apologize for the long messages. I really appreciate any help anyone could give me.

 

[southkogs]

Sounds to me like your water inlets are clogged (first guess, anyway). Water should push up through the system far enough to at least see it spitting out near the pivots.

I'm assuming this is a new-to-you boat? Or did the problem start after something happened?

To separate the upper and lower gearcase, I would suggest you remove the drive. I'm not sure of all of the steps, because your shift system should be hydro-electric (I think). But once the shift is disconnected, support the drive and remove the pivot caps and brackets.

To remove the upper from the lower gear case, simply disconnect the top cap off the drive. There are a few more bolts underneath if you want to remove the exhaust housing from the lower unit. Upper should lift (relatively easily) off the lower.

 

[GRANBATEAU]

Thanks so much for your reply. The water inlets on both sides of the lower drive look opened. The shift is just mechanical. What I tried to do was separate the two halves of the lower gear case and see if there is an internal blockage of some sort. I removed the 3 bolts around the trim tab area and the 2 bolts along each side of the bottom half of the lower gearcase half. I tried tapping with a hammer and a block of wood but no luck. I sprayed penetrating oil on the seam area and into each bolt hole but so far no luck. I'll try again tomorrow and see if I can separate the 2 lower halves. I did put water using a garden hose into the hose coming off the top of the intermediate drive and it comes out freely on the 2 areas on either side of the upper gear case where I removed the small rectangular covers. Thanks again and have a good evening.

 

[southkogs]

What I tried to do was separate the two halves of the lower gear case and see if there is an internal blockage of some sort. I removed the 3 bolts around the trim tab area and the 2 bolts along each side of the bottom half of the lower gearcase half.

That's not doing you any good. . Do you have a manual? You want to watch that shift cable pretty carefully on a mechanical. They're an expensive piece to replace when you can find 'em. I can't give you any tips on removing that cable, but you don't want to split the lower off with it attached I wouldn't think.

The exhaust housing (outside shell to the rear of the drive) helps clamp the lower unit on. The top cap screws into it and the upper gear case. When you release the top cap, that lower unit will begin to fall away from the upper - with the exhaust housing attached to it.

Typically I took the entire drive off and then separated them. Personally, I think that's the best way to do it. It's a lot easier to work on it that way too.

 

[GRANBATEAU]

Thanks for the ideas regarding the shift cable. I do have a manual and am reviewing it today. Thanks again and stay safe.