Engine cranks but won't catch - bayliner capri mercruiser Inboard outboard

[Kbb11]

We're having some trouble with our 2000 Bayliner Capri. It has a 3 litre Mercruiser engine. It's fussy to start. It will crank over and over and over but not catch. This is very hard on our starter and batteries. After about 10 mins of continuous trying it will finally catch and then it will run perfectly for hours. If it's shut off and sits for 10 minutes it won't start again, we're back to square one. Additional things we've noticed include - black smoke from the exhaust on initial start up but disappears once the engine has warmed up - runs a little rough on initial startup until engine warms up - the boat runs at 175 degrees - the oil pressure usually sits around 40 when were cruising along - the tachometer doesn't work Not sure if these have anything to do with the starting problem but wanted to mention them just in case. Any help would be greatly appreciated! Thanks in advance!

 

[saltybutwet]

sounds like you have a few issues going on. I'm no mercruiser mechanic, so maybe someone else will chime in also...have you checked your choke? Black smoke usually is a sign of running rich ( too much fuel)

 

[81 Checkmate]

If it has a carb.....sounds like you need a rebuild.

 

[stonyloam]

A little black smoke on start up is not unusual. It will run rich until the electric choke fully opens. Before you start it next time, take off the flame arrester and look to see the position of the choke butterfly, then at the helm push the throttle to WOT and back to idle. Look at the carb again. The choke should have closed. If not you might try adjusting the choke. Also after running a while, take another look to make sure the choke is fully open. It sounds like a fuel problem, either not enough or too much. What is your starting procedure?

 

[Bondo]

We're having some trouble with our 2000 Bayliner Capri. It has a 3 litre Mercruiser engine. It's fussy to start. It will crank over and over and over but not catch. This is very hard on our starter and batteries. After about 10 mins of continuous trying it will finally catch and then it will run perfectly for hours. If it's shut off and sits for 10 minutes it won't start again, we're back to square one. Additional things we've noticed include - black smoke from the exhaust on initial start up but disappears once the engine has warmed up - runs a little rough on initial startup until engine warms up - the boat runs at 175 degrees - the oil pressure usually sits around 40 when were cruising along - the tachometer doesn't work Not sure if these have anything to do with the starting problem but wanted to mention them just in case. Any help would be greatly appreciated! Thanks in advance!

Ayuh,.... Welcome Aboard,.... Are you usin' the Throttle durin' all this crankin' over the motor,..??
If so,.... How are ya Throttlin' it durin' all this crankin',...
I never crank a motor over more than 10, maybe 15 seconds,..... At that point it's time to see Why it ain't startin',...
Usually easier than changin' starters,....
Oh,.... Ya need a new Impeller too, at 175°, yer's is probably failin',...