Logo

Engine cuts outand

Ftgarlick

New member
This is my first boat, 1981 seaswril 16.4 foot with an Omc 3.8 litre. Person who I got the boat from said since the boat has sit and not ran for almost a year the engine may miss. First time out on water the boat ran like it was new for about 30-40 minutes then engine started to miss. Temp Gauge was not reading hot. As I came to a stop engine die. I tried starting the engine but took about 4 or 5 try's before it started up. Gave engine throttle but kept cutting out then at low throttle engine would die again. Finally got the boat onto its trailer and got the boat home. I checked the two fuel filters and on e was dirty. The inline filter looked new and it was clean, the one that went into the carb had some dirt in the filter. I check plugs and wires then took it back out to the lake and same thing but this time it took awhile to get the engine to start. It would start then die, this went on for 4-5 times before I got it to idle. I let it idle for 5 minutes then put in into gear at a light throttle and it ran like new. I gave it part throttle and it ran like new then gave it full throttle and it ran like new then just like the first time after running the engine for about 30-40 minutes it started cutting out or missing. Got it back to shore and check the filters again and the one that goes into the carb had dirt in it. Clean it on the spot and tried starting the engine and again it took 4-5 times trying to start the engine before it would start. Again ran like new for 30-40 minutes. Took it home an did more checking come to fine out that someone installed a elect fuel pump. Most elect fuel pumps that I have seen you also hear them run. This pump has no noise coming from it plus there is another inline fuel filter. What do you think is going on? My plans are remove the gas tank (10 gallons) and clean, replace the elect fuel pump and check fuel lines. Then remove the carb and check if float is dirty, replace plugs, wires, dist cap, rotor and points then take it for another test ride. Am I on the right track? I have no problems for that first 30-40 minutes, boat runs like new both low throttle and high throttle but wait then it starts missing then dies the engine. I need help. Thanks
 
Probably the issue is that you have gas with ethanol in that tank. The ethanol tends to loosen up all the old crap inside the tank, plus it eats away the inside of the fuel lines. Yes, clean out the tank, install new ethanol rated fuel line, and buy a new carb. Without pics hard to tell you what the fuel supply weirdness is all about.
 
Probably the issue is that you have gas with ethanol in that tank. The ethanol tends to loosen up all the old crap inside the tank, plus it eats away the inside of the fuel lines. Yes, clean out the tank, install new ethanol rated fuel line, and buy a new carb. Without pics hard to tell you what the fuel supply weirdness is all about.

I did everything that you said to do but when I took the carb off of the intake manifold I found this. Would this cause my problem? When taking the carb off I discovered that on the bottom of the carb when it mounts to the intake there is a crack....it looks like someone over tighten the nut. It runs great for about 30-40 minutes then starts cutting out. Maybe it takes the crack 30-40 minutes to get hot enough then the crack gets larger letting more air into the intake. Is that possible? The plate where you bolt the 4 nuts to the intake has a crack.
 
Back
Top