Agrifoglio
New member
Hi, I am new to this forum. I have a problem with my 1994 OMC Cobra 4.3 engine and I have no clue where to look further. Any help is appreciated (I am not a native speaker so please comment if anything is not clear).
Here is my case:
- I own this boat (Four winns Horizon 180) for over 20 years and never had any problems. I use it every summer and only did regular checks and maintenance on the engine: oil, filters (both fuel and oil), spark plugs, clean air filter.
- never needed to disassemble anything on the engine itself
- I started using the boat this summer, and after a week or so the problem started to appear
- When the engine is cold, it starts without a problem. I always wait 5-10 minutes for it to warm up before I load the engine. No problems here: water-skiing, traveling to other side of lake etc. Could use it for over 1-2 hours without pausing.
- now if I take a break of 45min-1,5 hours, it starts up again without a problem, but after a couple of minutes it dies down. I manage to start it up after pumping the gas handle several times (sometimes I have to try a couple of minutes, or over 20 times). Dies down independent of load ( happened on 1000 rpm or 3000 rpm)
- I checked the following things: fuel filter (is clean; did not replace it), vent (is OK), fuel tank (no visible signs of water or debris), disassembled the air filter on my carburetor and see the fuel coming in.
- at first I did not notice a pattern yet and I thought there was a problem with the fuel pump, so I replaced it with a new one. But without luck. The problem persists.
- what should be mist logical part to check next? Coil, distribution, carburetor...
- I have a strong feeling the problem is related to fuel supply, but what logical explanation could there be for the pattern I described (only appears after approximately 1 hour break on warm engine, and even then after a couple of minutes)? The reason I think it is related to fuel supply is that it does not go down immediately, but still reacts a bit on the throttle handle (if I pump the gas handle, it goes down slowly). Prime suspect was the vent, but as described I checked that and seems to be OK)
Any help or suggestion would be greatly appreciated! Do not want to change parts randomly (already spent a lot of money on the fuel pump which costed me over 400 euros).
Here is my case:
- I own this boat (Four winns Horizon 180) for over 20 years and never had any problems. I use it every summer and only did regular checks and maintenance on the engine: oil, filters (both fuel and oil), spark plugs, clean air filter.
- never needed to disassemble anything on the engine itself
- I started using the boat this summer, and after a week or so the problem started to appear
- When the engine is cold, it starts without a problem. I always wait 5-10 minutes for it to warm up before I load the engine. No problems here: water-skiing, traveling to other side of lake etc. Could use it for over 1-2 hours without pausing.
- now if I take a break of 45min-1,5 hours, it starts up again without a problem, but after a couple of minutes it dies down. I manage to start it up after pumping the gas handle several times (sometimes I have to try a couple of minutes, or over 20 times). Dies down independent of load ( happened on 1000 rpm or 3000 rpm)
- I checked the following things: fuel filter (is clean; did not replace it), vent (is OK), fuel tank (no visible signs of water or debris), disassembled the air filter on my carburetor and see the fuel coming in.
- at first I did not notice a pattern yet and I thought there was a problem with the fuel pump, so I replaced it with a new one. But without luck. The problem persists.
- what should be mist logical part to check next? Coil, distribution, carburetor...
- I have a strong feeling the problem is related to fuel supply, but what logical explanation could there be for the pattern I described (only appears after approximately 1 hour break on warm engine, and even then after a couple of minutes)? The reason I think it is related to fuel supply is that it does not go down immediately, but still reacts a bit on the throttle handle (if I pump the gas handle, it goes down slowly). Prime suspect was the vent, but as described I checked that and seems to be OK)
Any help or suggestion would be greatly appreciated! Do not want to change parts randomly (already spent a lot of money on the fuel pump which costed me over 400 euros).