Hi, been a long time reader of this forum, but this is the first time I've needed to ask something. I have a 2005 3d with a new 787 rfi engine. (The last one had a leaky inner crank seal last summer, allowing a lot of oil into the cylinder head. It wouldn't start because it was oil locked. I read on here to take the spark plugs out and blow all the oil out by trying to start the engine a few times. This worked for about a week, then blew up.)
I installed the new engine last weekend with some friends who are more mechanically capable than I am, and it started up great. I idled it on the trailer for 10 minutes, with water hooked up, then turned it off and headed to the river today. Once I got here I ran it for 30 minutes never exceeding 20% throttle and I varied the speed every few seconds. Towards the end of the 30 minutes I heard a knock. About 30 seconds later I heard another knock. I then idled back to shore to let it cool down. When I went back to start it 45 minutes later and it really struggled. The starter sounded great, but it wouldn't stay running. Finally it stayed running and I went out riding planning to take it up to 50% throttle. It didn't like that. It really bogged down. So I brought it back in and checked the plugs. They're grey, with not much oil on them. I think that's ok?? After trying to start it again without my body weight on it, it started up ok but doesn't sound right. It died whenever I try to get on it. It clearly doesn't like the additional resistance of having to push more water thru the jet and the exhaust gases having to push more as well. The weird thing is, when I press the button to turn it off, for that second the engine sounds perfect. I've done it 5 times and every time I turn it off it sounds great for a second. Could this be an electrical issue? Or a fuel issue? My batteries a few years old, but I put it on the maintainer on it for a couple of days each month. It's a sealed battery so I can't tell the level of the acid. Any help would be appreciated. Thanks
I installed the new engine last weekend with some friends who are more mechanically capable than I am, and it started up great. I idled it on the trailer for 10 minutes, with water hooked up, then turned it off and headed to the river today. Once I got here I ran it for 30 minutes never exceeding 20% throttle and I varied the speed every few seconds. Towards the end of the 30 minutes I heard a knock. About 30 seconds later I heard another knock. I then idled back to shore to let it cool down. When I went back to start it 45 minutes later and it really struggled. The starter sounded great, but it wouldn't stay running. Finally it stayed running and I went out riding planning to take it up to 50% throttle. It didn't like that. It really bogged down. So I brought it back in and checked the plugs. They're grey, with not much oil on them. I think that's ok?? After trying to start it again without my body weight on it, it started up ok but doesn't sound right. It died whenever I try to get on it. It clearly doesn't like the additional resistance of having to push more water thru the jet and the exhaust gases having to push more as well. The weird thing is, when I press the button to turn it off, for that second the engine sounds perfect. I've done it 5 times and every time I turn it off it sounds great for a second. Could this be an electrical issue? Or a fuel issue? My batteries a few years old, but I put it on the maintainer on it for a couple of days each month. It's a sealed battery so I can't tell the level of the acid. Any help would be appreciated. Thanks
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