Motor problem with 80s 140 mercruiser 3l

[Kenneth15432]

So I was out the other day down the river motor was running fine then just stopped out of the blue should it was somthing simple so i pulled the engine cover and cranked the engine and it was puffing out of the carb so i took the oil cap off and got someone to crank the motor and the rockers wernt moving same with the rotor in the distributor I'm wondering if these engines have a timing chain or belt and if it is a interference motor boat is down the river right now so I'm looking to see if I can just get a new chain or belt

 

[Bondo]

so I'm looking to see if I can just get a new chain or belt

Ayuh,...... Welcome Aboard,... It uses a matched set of gears,..... 1 steel, 'n one fibrous,....

 

[Kenneth15432]

So I probably stripped the fiber gear? Is it an interference engine like are the valve ok?

 

[Scott Danforth]

the motor uses timing gears.

they are clearance motors

the motor needs to come out and go on a stand as you need to drop the pan to get the timing cover off.

you are fooling yourself if you think you can do it in the boat.

factory gears are steel and fiber like Bondo mentioned. there are also higher grade which are bronze and hardened aluminum