1973 85HP Mercury

[SteveandCarrie]

I just purchased this and was wanting to know if this is a good OBM. I know nothing about it. It runs kind of rough. Not real smooth. It runs and will run normal at fast speeds. When going slow or Idleing its rough. Also the throttle handle will not stay down and the tightener is tight. The throttle handle is also missing the finger clutch or what ever it is called. Can the handle be replaced or will the whole unit need replaced?

 

[MUCSTAK]

Re: 1973 85HP Mercury

If you need to buy a new (aftermarket) controller go here:www.tfxmarine.com. If you have questions talk to " <joe.tornetta@tfxmarine.com> ". He can help.<br /><br />As far as the engine itself, inspect very closely for corroded wiring with broken insulation. Not only inder the motor cover but from the controller to the motor. These year Mercs were notorious for corroded wiring as an aluminum alloy was used often instead of copper.<br /><br />If the compression is good on all 4 cyls, there are no cooling water leaks where there are not supposed to be and the prop turns forward and reverse.......it is a keeper. Good luck

 

[kevlar3000]

Re: 1973 85HP Mercury

In general if it is in good mechanical condition then they are great engines. If it has some problems then it is only as good as those problems will allow it to be. It has some years on it..... Do you run with a Tach? What are the rpms? If not a compression check is helpful to check general health. <br /><br />It may have dirty carbs, need a fuel pump rebuild kit ( very cheap) , have weak spark ect... What additional info do you have on it?