1971 Mercury 500

[71ranger]

I have a Mercury 500, with the motor running the prop spins but moving the shifter does not go into forward or reverse. I have removed to cable and moved the shift linkage but that does noting either. When moving the shift linkage it feels pretty loose. Is it possible the the shifter or linkage in the lower unit is broken? Not sure where to start. The motor was this way when I bought it on the boat. Any information would be helpful. Thanks

 

[carholme]

Re: 1971 Mercury 500

If you cannnot shift it by hand with the cables removed, it is time to drop the lower unit and see where the problem lies.

Do you have a manual and the parts list? If not, please let us know your engine s/n.

Here is a link to the upper shift shaft, item 23, which you should see moving when you do it by hand:

Mercury & Mercruiser Parts, EXHAUST EXTENSION PLATE AND SHIFT LINKAGE, MERC 500

Gerry

 

[71ranger]

Re: 1971 Mercury 500

It is Mercury 500 Serial number 2947834. Everything in the top moves like it should, It just doesn't feel like it is connected to anything in the bottom.

 

[carholme]

Re: 1971 Mercury 500

That s/n comes up as:

50 500 4-cyl 2736807 3008818 1970 USA

From here:

Mercury 2-takt, 4-cyl, 40 - 85 hp, produktions?r, modellguide

It is a model 1500100

Parts Listing:

Mercury Parts, MERC 500-7/8

Here is a link to the condensed version of the Clymer service manual. Download it soonest to your computer as it is short lived:

Small Engine Repair Reference Center Home

You now have to drop the lower unit to see where the problem lies. Could be a broken upper shift shaft, worn splines at the upper to lower coupler or damage in the gearcase. You just have to get it off to see.

Gerry