OMC Stringer 800 help

[BrokenRoadsII]

Hi Forum! We have acquired a '78 Ebko 19 Tri-Hull. OMC 800. Now I know the issues with OMC, people tell you to trash it etc. Before anyone starts down that road, I am not considering it. The boat has a cool retro 70s thing going on so we are prepared to fix. Has the hydro-mechanical system, first year I believe. Issue is boat will not shift into reverse unless helm cable is disconnected at controller and shift cams are move the extreme of the throw in reverse.

1. Possible solutions? Bad cable? is their a hydraulic pump I should look at/renew fluid?
2. What is the possibility of converting to a full mechanical system?

I have considered the conversion to Mercruiser. I see a lot of stuff out there about filling the hole with two inches of plywood, but it seems to me that the proper fix is marry the entire transom to the gunwales somehow because the added weight without mechanical support to the sides and stringers makes no sense.

Any help/ideas is appreciated. I am highly mechanical, can do most work myself. Thanks for the help!

 

[southkogs]

Welcome Aboard:

I can't answer your questions about the hydro-mechanical shift. I don't really know 'em. Mine was electric shift.

I do know you can convert over to full mechanical, and it's easier than converting to Mercruiser. To go to Merc, you really need to rebuild and reglass the transom. If that become the only hope, cut your losses and move on. A couple of guys on here know your shift set, so hang in ...

... or look for a mechanical if you like. You'll need everything from the intermediate on to the prop, and you need to make sure you've got the same gear ratio.

 

[BrokenRoadsII]

Thanks for the fast reply, southkogs. I wouldn't object to converting to the mechanical system if I run into a brick wall otherwise. How do determine ratios?

 

[southkogs]

LOL ... now that you ask that, I'm not sure if it's listed on the upper gear case or not. The housings all pretty much have the same part number. I always knew by what model (HP and number) the ones I scavenged were attached to.

That said, keep careful watch on Craigslist, and you may find a donor with the right system you can pull the whole set from. Patience is usually a big help

 

[THE BEEF]

When I changed my 800 stringer from hydro. to full mech. this is what I did.
First find a lower full mech with shift cable, it will have a anode in the back in the housing I found mine on E bay.Then you need to get a shift converter that your shift cables go into, the converter will have 2 switches on it. Also you will need a mech. conversion kit. This will have the wiring harness, clamps, and shift interrupter and instructions to convert. I found all this on E bay. your upper gear box with the water pump will bolt right up to the unit.the 2 switches on the converter are micro switches, one is normally open, one normally closed, The normally open is on the right side of the unit,when you shift into gear this switch closes and turns on the spark interrupter and causes the engine to stumble as you move the gear shift the second switch the normally closed on the left side will open causing the spark interrupter to drop out and the engine will run smoothly, This happen in less the a second so you won't notice it. When you go into neutral the the same thing happens in reverse, The spark interrupter comes on engine stumbles,come out of gear and turns off when in neutral. Sounds confusing , I tried to explain it the best way I can. If this does not happen you will need King Kong to get it out of gear. When the spark interrupter turns on it comes out of gear easy thats how it works.
Another tip, when you pull the lower unit change the water pump and grease the splines also on the new mech. unit change the swivel bearing grease seals.
splines need greased to keep from wear, The seals keep exhaust gasses from getting sucked up in the cooling water and cause over heating,
Send me a PM and I'll give you a call I have a factory manual. Take care.

 

[THE BEEF]

You can Email me at vonbeeferii@aol.com
The Beef