D
DeuceisWild
Guest
"First I would like to say Tha
"First I would like to say Thank You to the many contributors of this forum. I have owned out/board boats for 20 years and have had friends with in boards, but this is my first. I have referred to this sight many times and have learned quite a bit from your replies.
I own a 1988 Tiara 3300 Open with a small Marlin tower. Before my ownership the boat was re powered in 2001 with Crusader 8.1 MPI. I bought the boat in Oct of 05 with 200 hours on the engines and am now up to 350 hrs. I have been generally happy with their performance. After fixing a Floscan a few months back, I noticed the Port was using 2 gal per hr more than the Strb at cruise. I know that’s not right. Switched sensors on the Floscan and the problem did not follow. Props were reconditioned for another reason, but no change in fuel usage.
I purchased the Diacom software to see live data produced by the ECM (MEFI 4) on my lap top and compare the engines performance in real time to each other. There is a Power Balance test included. This allows you to “Turn off” one cylinder at a time to see if there is a change in RPM. No change in RPM equals no contribution from that cylinder. My #2 and #6 firing order cylinders showed no change to RPM when disabled.
Pull the wires and heard plenty of spark. Pulled the plugs and they look normal. (Only 50 hours on them) I moved those plugs to other cylinders and re tested. The problem did not follow the move. Now I’m thinking fuel injectors.
I fill a small can with gas and added Sea foam. Ran the engine for about 1.5 hours. Retested. Now the # 2 and #6 show a 50 rpm drop when disabled. I think I'm on the right track with this positive result. I plan to run some more injector cleaner thru the system. I have read the tech manual on how to remove and replace injectors. This might be more than I want to tackle on my own. Should I look for a mechanic on this? Will cleaner handle the problem? Can they be cleaned or do they need replacing? You advice is greatly appreciated."
"First I would like to say Thank You to the many contributors of this forum. I have owned out/board boats for 20 years and have had friends with in boards, but this is my first. I have referred to this sight many times and have learned quite a bit from your replies.
I own a 1988 Tiara 3300 Open with a small Marlin tower. Before my ownership the boat was re powered in 2001 with Crusader 8.1 MPI. I bought the boat in Oct of 05 with 200 hours on the engines and am now up to 350 hrs. I have been generally happy with their performance. After fixing a Floscan a few months back, I noticed the Port was using 2 gal per hr more than the Strb at cruise. I know that’s not right. Switched sensors on the Floscan and the problem did not follow. Props were reconditioned for another reason, but no change in fuel usage.
I purchased the Diacom software to see live data produced by the ECM (MEFI 4) on my lap top and compare the engines performance in real time to each other. There is a Power Balance test included. This allows you to “Turn off” one cylinder at a time to see if there is a change in RPM. No change in RPM equals no contribution from that cylinder. My #2 and #6 firing order cylinders showed no change to RPM when disabled.
Pull the wires and heard plenty of spark. Pulled the plugs and they look normal. (Only 50 hours on them) I moved those plugs to other cylinders and re tested. The problem did not follow the move. Now I’m thinking fuel injectors.
I fill a small can with gas and added Sea foam. Ran the engine for about 1.5 hours. Retested. Now the # 2 and #6 show a 50 rpm drop when disabled. I think I'm on the right track with this positive result. I plan to run some more injector cleaner thru the system. I have read the tech manual on how to remove and replace injectors. This might be more than I want to tackle on my own. Should I look for a mechanic on this? Will cleaner handle the problem? Can they be cleaned or do they need replacing? You advice is greatly appreciated."
