Hi all!
I have searched the forums and got some good tips on this; my situation is slightly different so I wanted to post. I have a 1988 Dynasty Apollo with a 4.3L Mercruiser Alpha I with a 4 BBL Carb. I bought the boat last summer and had it tuned up and it ran great all summer long with a top speed of 52MPH at 4500 RPM. I winterized it according to manual (treated fuel, etc), and de-winterized this spring. I took it out to the lake last weekend. Started right up, and off I went. As I hit open water, I pegged the throttle and got to 49 MPH at 4400 RPM. A minute later, the engine bogged down. As the boat rocked back and forth, the engine would bog, then catch up, then bog again, slowly losing RPM every time. I found that if I backed off to around 3K, it ran great with 0 issues. If I stop and sit for a minute and try again, it gets right up on plane, runs good for a minute, then does the same thing again. The engine will rev right up when not under load. I suspected a fuel issue, so I did some quick troubleshooting on the lake: Up to this point, I have: checked the linkages to be sure they are functioning (4 barrels opening, etc), made sure fuel is getting to carb.
I have seen some tips on cleaning/changing fuel filters and water separators, fuel pumps, points, and even replacing the carb. I'm not above taking it to a shop, but I like to know whats going on and know its something I can't fix before I go taking it somewhere and paying big bucks. I personally suspect a fuel filter (specifically, the one right by the carb) but its just a hunch) but wanted to check what others think before I go ripping in to it this weekend. I live an hour from the lake so its hard to 'try one thing then test', especially since its only happening under load, so Im trying to get the most likely suspicions out of the way.
I appreciate you all, as always!
Rob
I have searched the forums and got some good tips on this; my situation is slightly different so I wanted to post. I have a 1988 Dynasty Apollo with a 4.3L Mercruiser Alpha I with a 4 BBL Carb. I bought the boat last summer and had it tuned up and it ran great all summer long with a top speed of 52MPH at 4500 RPM. I winterized it according to manual (treated fuel, etc), and de-winterized this spring. I took it out to the lake last weekend. Started right up, and off I went. As I hit open water, I pegged the throttle and got to 49 MPH at 4400 RPM. A minute later, the engine bogged down. As the boat rocked back and forth, the engine would bog, then catch up, then bog again, slowly losing RPM every time. I found that if I backed off to around 3K, it ran great with 0 issues. If I stop and sit for a minute and try again, it gets right up on plane, runs good for a minute, then does the same thing again. The engine will rev right up when not under load. I suspected a fuel issue, so I did some quick troubleshooting on the lake: Up to this point, I have: checked the linkages to be sure they are functioning (4 barrels opening, etc), made sure fuel is getting to carb.
I have seen some tips on cleaning/changing fuel filters and water separators, fuel pumps, points, and even replacing the carb. I'm not above taking it to a shop, but I like to know whats going on and know its something I can't fix before I go taking it somewhere and paying big bucks. I personally suspect a fuel filter (specifically, the one right by the carb) but its just a hunch) but wanted to check what others think before I go ripping in to it this weekend. I live an hour from the lake so its hard to 'try one thing then test', especially since its only happening under load, so Im trying to get the most likely suspicions out of the way.
I appreciate you all, as always!
Rob