75 merc 850 starts right up but revs super high

[Baylinercapri1985]

Hey guys I bought a old 1975 merc 850 thunderbolt ignition off craigslist. It had been sitting for years so I got it cheap I had to play with it a little but she fired right up and ran good, shifts good everything seems to be working But here's my problem.. She'll start right up but when she does it's like the idle rpm is super high I mean this motor roars and spins super fast at a constant Now that being said I can shift it. Into gear F or R fine and with more throttle it revs and spins faster like it should so I'm thinking the idle is just too high but I don't know how to adjust them on these old motors But maybe I'm wrong and that's not it Maybe that's how it's supposed to sound and run although it deff sounds like something's not right

 

[Chris1956]

Remove the wrap cowl. The top control cable is the throttle cable. It should be adjusted to push the throttle against the idle stop. The idle stop screw can be turned to lower the idle speed, and the throttle cable adjusted to push the throttle closed. Both adjustments must be done to be effective.