Hi,
I've got a 2000 21V with a Mercury 5.7 (Mag MPI) that I've been having some issues with since the fall. Here's what has happened:
- Last October, it threw the belt, overheated, and sucked water into the cylinders when I turned it off. I replaced the belt, impeller (old one was fully intact), oil, and spark plugs. It ran fine for the rest of the fall (only about 3 hours until I put it away for the winter).
- When I put it in the water this spring, it was very difficult to start. After cruising at 5 mph for 5-10 minutes, it overheated. It had thrown and chewed up one rib of the belt. I noticed the circ pump pulley had a wobble, so I replaced the belt, circ pump, and circ pump pulley.
- It then ran fine for an hour test drive.
- Next time I took it out (with lots of kids of course), it overheated and sucked water into the cylinder again. This time the belt stayed on fine. I got towed home, removed the water from the cylinders and ran it for 5 minutes with a hose connected. The belt stayed on again.
Any suggestions on what to look at? It seems like the belt issue and it overheating are likely related. Maybe I fixed the belt getting thrown when I replaced the circ pump. Just not sure why it is still overheating now.
I've got a 2000 21V with a Mercury 5.7 (Mag MPI) that I've been having some issues with since the fall. Here's what has happened:
- Last October, it threw the belt, overheated, and sucked water into the cylinders when I turned it off. I replaced the belt, impeller (old one was fully intact), oil, and spark plugs. It ran fine for the rest of the fall (only about 3 hours until I put it away for the winter).
- When I put it in the water this spring, it was very difficult to start. After cruising at 5 mph for 5-10 minutes, it overheated. It had thrown and chewed up one rib of the belt. I noticed the circ pump pulley had a wobble, so I replaced the belt, circ pump, and circ pump pulley.
- It then ran fine for an hour test drive.
- Next time I took it out (with lots of kids of course), it overheated and sucked water into the cylinder again. This time the belt stayed on fine. I got towed home, removed the water from the cylinders and ran it for 5 minutes with a hose connected. The belt stayed on again.
Any suggestions on what to look at? It seems like the belt issue and it overheating are likely related. Maybe I fixed the belt getting thrown when I replaced the circ pump. Just not sure why it is still overheating now.