Hey everyone! New to the boating world but not necessarily to mechanical things. Just bought (what I thought was a clean, low hour) 2000 Caravelle with a Volvo 5.0 Gi. Took it out for the weekend. The engine starts and runs so smooth. Above 3000 rpms though it will eventually start to lose power, miss, run rough then die. If I turn the ignition off and back on and immediately restart the engine it will be ok for a while then start doing the same thing. Below 3000 it will basically run all day without hiccup. But above it will run roughly 30-60 seconds, maybe a little more, before it does it. If I try to let it idle it’s way out it won’t. In other words once it starts to run rough there is no recovery. But off and on again (even very quickly) makes it run perfect again. Odd enough if I let it stall but don’t turn the ignition off and just restart that does not fix it. It seems to want an ignition recycle.
some things I checked. Obviously oil pressure and temps are ok. Battery is good. Fluids good. Fuel new. Cap and rotor look new not so much the plug wires though. I pulled the anti siphon valve out and somebody replaced it with just a plain elbow. Draw straw does not seem to be restricted. We tried venting the fuel cap by loosening that didn’t seem to help. Did a general inspection for looks wires or anything odd and didn’t seem much. I checked the ignition switch and General area of wires for loose connections. Nothing.
I’m confused on why a quick reset makes it run better. Again keep it under 3000 and it runs perfect all day. Drop the hammer and take it up (with a couple of people in the boat it would spoil up to 4500ish) above 3000 and you can take a check to the bank that you’ve got 30-60 seconds of fun before you start hearing some missing and loss of power.
Oh and during power cycle you can hear the pump momentarily. I know that doesn’t mean it’s working perfectly. But again I’m not sure why a power cycle would help the pump out and not just a restart without power cycle (or even letting the engine idle for a while to recover low fuel pressure).
sorry for being windy I am just a little perplexed! Thanks! And sorry for typos I’m using my phone.
some things I checked. Obviously oil pressure and temps are ok. Battery is good. Fluids good. Fuel new. Cap and rotor look new not so much the plug wires though. I pulled the anti siphon valve out and somebody replaced it with just a plain elbow. Draw straw does not seem to be restricted. We tried venting the fuel cap by loosening that didn’t seem to help. Did a general inspection for looks wires or anything odd and didn’t seem much. I checked the ignition switch and General area of wires for loose connections. Nothing.
I’m confused on why a quick reset makes it run better. Again keep it under 3000 and it runs perfect all day. Drop the hammer and take it up (with a couple of people in the boat it would spoil up to 4500ish) above 3000 and you can take a check to the bank that you’ve got 30-60 seconds of fun before you start hearing some missing and loss of power.
Oh and during power cycle you can hear the pump momentarily. I know that doesn’t mean it’s working perfectly. But again I’m not sure why a power cycle would help the pump out and not just a restart without power cycle (or even letting the engine idle for a while to recover low fuel pressure).
sorry for being windy I am just a little perplexed! Thanks! And sorry for typos I’m using my phone.
