hydromechanical

[carguy5068]

I have a gorgeous 19ft 79 cobalt boat that has been pampered all its life. never seen weather. I bought it from origional owner who rebuilt the impeller and bearings at the end of last season. since the rebuild the boat quit shifting smoothly now not shifting at all. origional owner claims that he had outdrive supported on cherry picker and either release valve wasnt tight or his kid messed with it. regardless the unit hung on shift cable. I purchased a used cable assembly and was just wondering if it could be something else causing problem. havent recieved too much good news about the hydromechanical shift but others have said they work good when properly adjusted. boat starts, runs and sounds awesome but when i try shifting foreward or reverse i get a growling sound like not totally engaging. guess my question is do you think the cable is the problem or do you think the owner messed something else up replacing impeller? also what am i looking at cost wise to have professional replace cable? thanks in advance mark...

 

[Howard Sterndrive]

Re: hydromechanical

apparently, one of the main issues with those lowers, is water in the lube rusting/seizing the hydro assist plunger. If there has ever been milky lower gear lube, could be the issue.

 

[carguy5068]

Re: hydromechanical

thanks! have lower unit off. everything seems fine with it. is this plunger on the shift cable mechanism? or is it in the upper drive? when the lower unit was attatched and engaged in gear if you turned hard on the prop it would pop out of gear or slip. but no slippage in lower unit itself so problem must be in upper drive. when i turn rear ball gear it dosen't turn the splines where lower unit shaft joins. ball gears are worn badly and of course i have the obsolete bolt in type. thinking shaft on rear ball gear could be broke but just a guess. hoping you could narrow down my guess work. going to pull rear ball gear today also wondering if i can weld up those worn balls on ball gears and reshape? your help greatly appreciated and big thanks in advance mark...

 

[Howard Sterndrive]

Re: hydromechanical

1979 ball gears are not obsolete. They are the most common type- still available from Evinrude.

As far as the slipping, it sounds like w/p shaft splines have stripped. The water pump shaft is the shaft connecting the upper and lower gearcases. it also drives the impeller thus the name.

common problem when the impeller isn't serviced regularly on stringer drives. The spline grease only lasts a few seasons. After it has washed out, the splines fail.