1986 115 Inline 6 Water Pump

[popknot]

Getting ready to try and replace my Water Pump. My shop manual lists 3 types of Lower Units, Cam Shift l & ll and EZ shift. It says the EZ Shift needs to be in Neutral When you drop the Lower Unit and the Cam shift needs to be in forward. Not sure which I have. I THINK its the EZ Shift but not sure. Any Help? Thanks.

 

[Texasmark]

Re: 1986 115 Inline 6 Water Pump

Seems some manuals specify one and others the other. Having replaced a few pumps in the day, I have 2 schools of thought regardless of the type tower LU you have.

1. Neutral. Detents on shift cam in the LU are 3. N is the center one. Easy to find it when rotating the shift lever. Detent for N in the remote is easily centered whereas F and R can be somewhat vague. To install the cover on the pump a pair of visegrips on the top of the drive shaft is required to rotate the shaft/impeller as you push the cover down. You do not have the ability to rotate the prop with one hand while pushing up on the LU to get the drive shaft spline to mate with the crankshaft during installation.

2. Forward. Detent on one end, not too hard to find, remote positioning is sloppier and can rotate the prop and cause the impeller to turn initially and later rotate the drive shaft to mesh with the crankshaft.

Seems some like 1 and others 2. I guess I like 1 because of the (more) positive location of shift points.

I guess if there is some other mechanical reason for one over the other as a function of which LU you have someone else has to mention it.

Mark

 

[popknot]

Re: 1986 115 Inline 6 Water Pump

Ok. Thanks for the quick Reply Texasmark. So sounds like I could do it either way. Just a little different process liniing everything back up when I reassemble everything. Is that correct?

 

[racerone]

Re: 1986 115 Inline 6 Water Pump

Put it in forward and drop the lower unit down.-----Don't forget the bolt under the trim tab.

 

[Chris1956]

Re: 1986 115 Inline 6 Water Pump

I like to put the gearcase and control in neutral, before disassembly. I find it much easier to reassemble them in neutral, so the shift shafts align properly. You will need to turn the flywheel by hand to mate the driveshaft splines, but that is no issue.

Mercruisers need to be in forward in order to drop the gearcase. Perhaps that is what you are seeing in the service manual.

 

[Vision91]

Re: 1986 115 Inline 6 Water Pump

a quick and easy test can and should be made to determine if the unit being serviced has the Cam shift or the EZ shift. With the powerhead still attached to the lower unit, simply shift the unit into reverse gear. now attempt to rotate the propeller shaft counterclockwise. if the unit has the "cam-shaft" gear housing, the propeller shaft will not rachet as it is rotated counterclockwise with the unit in reverse. if the unit has the E-Z shift the propeller shaft will rachet when turned counterclockwise.


this was taking from the complete engine manual i have

 

[popknot]

Re: 1986 115 Inline 6 Water Pump

a quick and easy test can and should be made to determine if the unit being serviced has the Cam shift or the EZ shift. With the powerhead still attached to the lower unit, simply shift the unit into reverse gear. now attempt to rotate the propeller shaft counterclockwise. if the unit has the "cam-shaft" gear housing, the propeller shaft will not rachet as it is rotated counterclockwise with the unit in reverse. if the unit has the E-Z shift the propeller shaft will rachet when turned counterclockwise.


this was taking from the complete engine manual i have

This is what my manual states also. I assume you would have to remove all the plugs first. But I wasnt exactly sure what they meant by "Rachets". After researching a little and comparing pictures of each LU in the manual Im pretty sure my is the EZ shift and needs to be in nuetral. Think thats the route I'll go. Thanks for all the responses. I'm sure as I proceed I'll have more questions. Thanks again for all the help.

 

[Imjus4u2nv]

Re: 1986 115 Inline 6 Water Pump

Hey popknot- any update?
I just had to get the seals replaced on my lower unit (90hp 1986 Mercury inline 6), after putting the unit back on (Left it in neutral as mine also ratcheted) I have no neutral or reverse. Had a hard time getting the lower unit all the way back in. Any ideas on what to do to fix this?

 

[racerone]

Re: 1986 115 Inline 6 Water Pump

Here is what usually happens.----Lower unit is taken off with control in nuetral.---------Then during the transport / repair of the unit the spring in the propshaft pops it into forward.-----On assembly the shift splines are out of sync.-----------So take the lower unit off again put it in nuetral and have the control in nuetral.----Or if you wish ensure the lower unit is in forward and the control in forward. then re-assemle.

 

[CharlieB]

Re: 1986 115 Inline 6 Water Pump

Go with the Neutral assy. Using Forward you can still have the shift spline indexed incorrectly.