I have a Mercruiser 350 5.7L 260 HP 1990.
In 2014 we had the mechanic put on a new carburetor due to leaking at the bushings. We took it back to him within a month because it had a lot of black smoke and a lack of power. He installed a new electric fuel pump, he installed a new starter, changed the oil and filter, and put the jets from the old carburetor into the new one. If I recall, I think he said the old ones were smaller.
It continues to blow black smoke, and has a lack of power, and smells of gas which is scary for us. We maybe take it out 2 times a season. One time out we tried to pull experienced skiers and it would not plane. It drove fine at the end of last season, but we were pulling small kids on tubes. Then later in the day,some adults wanted to try, and it started to bog. Literally ran it for 3 hours and it all of a sudden died. But, we also noticed it was going through a whole tank of gas in 3 hours. It would not restart, but the battery was iffy. We contacted the mechanic, no reply, so we decided to take it out for the day, and then put it away for the season. The mechanic replied later that when the new carb went on, it had a choke issue. That was news to us?? We question why it was not handled right away.
So, now 2016 we take it out of storage right to the mechanic. I ask for the choke and power and black smoke to be fixed. After weeks, I finally get a reply the late afternoon before we want to use it, that he can not figure out the power issue,and figures it is blow by, so a piston ring issue. We can get a year out of it,but it will need a costly rebuild. I have stated that due to my kids now being adults and not using the boat often, we have wanted to sell it now for 3 years now, but put it in water to make sure it is sellable, as we are honest and don't want to cheat anyone. He says it usable for our next day event, but suggested to buy a prop 2 sizes down, so it has more power. He says it will work. We discuss the selling, and he says, I can sell it as a handyman special and give the diagnosis. The next morning on the way, I buy the prop, plus a new battery.
Mr gets to the landing, son starts it, could not take it off of high idle, or it would die. Finally gets it running, backs out, throttles it with him and 1 other passenger, it just plows, Throttle acts like nothing, no get up to go, it just plows. Son is beyond frustrated. They put it back on the trailer and pull it out.
Later they are sitting around the fire, talking to neighbors, friends. We discuss how we will need to sell it as a handyman special, and be honest about the history.But response is that many question if it is a too much gas issue! I text the mechanic if he did a compression test, get no as an answer. I get home, call a local boat repair, find out I can get in, in maybe 6 weeks. My fear is I am selling a good boat for cheap without the proper answers. So, I call a guy I know who is a car mechanic kind of friend and ask if he can run over and do a compression test. He pulls 2 plugs, says no way is this a compression issue,plugs show it is a too much gas issue! He also points out that the power is off, and the choke is open, and should be closed, and how much gas he can smell even though we never turned the boat on. He also checks the oil, and it is full and does not have gas in it, and we did not change it, so if it was a compression issue, it would not be full. The second plug was hard to get back in, so $60 paid. He leaves, saying he will come back later when Mr gets home and we are going to put it on water for him to test. He comes back, and talking, he discovers it has an electric fuel pump, which I thought he had seen earlier as he was listing all the new things he could see that were installed.He says he would guarantee it is the fuel pump pushing too much gas....talks about he thinks it causes the carburetor and plugs to foul out. He tells us we need to regulate the gas from the fuel pump. Says my Mr can buy and install anew fuel pump that is adjustable.
I've been on internet and can not find such a thing. He said another option would be to put a fuel flow regulator in there. In looking up Electric Fuel Pumps, we thought that we had discovered an issue. One we were looking at, marine said it was 2.5 - 4.5 psi. Our auto mechanic friend said a marine one should be 2-4 psi. But we ended up calling our local Marine part dept and found out that a mechanical one is 5-7 psi. Our boat does not call for an electric one, but if we were to get one they recommend a 8 psi. The one our boat has is an auto one, but has 9 psi.
We were thinking the next option would be to install an inline regulator and pressure gauge, but now are totally lost?
We do have an appointment with a Marine Dealer Repair Shop on July 5, but wanted to get the boat working and for sale before then.
I hope I explained this all enough for someone to help me. What do you all think???
In 2014 we had the mechanic put on a new carburetor due to leaking at the bushings. We took it back to him within a month because it had a lot of black smoke and a lack of power. He installed a new electric fuel pump, he installed a new starter, changed the oil and filter, and put the jets from the old carburetor into the new one. If I recall, I think he said the old ones were smaller.
It continues to blow black smoke, and has a lack of power, and smells of gas which is scary for us. We maybe take it out 2 times a season. One time out we tried to pull experienced skiers and it would not plane. It drove fine at the end of last season, but we were pulling small kids on tubes. Then later in the day,some adults wanted to try, and it started to bog. Literally ran it for 3 hours and it all of a sudden died. But, we also noticed it was going through a whole tank of gas in 3 hours. It would not restart, but the battery was iffy. We contacted the mechanic, no reply, so we decided to take it out for the day, and then put it away for the season. The mechanic replied later that when the new carb went on, it had a choke issue. That was news to us?? We question why it was not handled right away.
So, now 2016 we take it out of storage right to the mechanic. I ask for the choke and power and black smoke to be fixed. After weeks, I finally get a reply the late afternoon before we want to use it, that he can not figure out the power issue,and figures it is blow by, so a piston ring issue. We can get a year out of it,but it will need a costly rebuild. I have stated that due to my kids now being adults and not using the boat often, we have wanted to sell it now for 3 years now, but put it in water to make sure it is sellable, as we are honest and don't want to cheat anyone. He says it usable for our next day event, but suggested to buy a prop 2 sizes down, so it has more power. He says it will work. We discuss the selling, and he says, I can sell it as a handyman special and give the diagnosis. The next morning on the way, I buy the prop, plus a new battery.
Mr gets to the landing, son starts it, could not take it off of high idle, or it would die. Finally gets it running, backs out, throttles it with him and 1 other passenger, it just plows, Throttle acts like nothing, no get up to go, it just plows. Son is beyond frustrated. They put it back on the trailer and pull it out.
Later they are sitting around the fire, talking to neighbors, friends. We discuss how we will need to sell it as a handyman special, and be honest about the history.But response is that many question if it is a too much gas issue! I text the mechanic if he did a compression test, get no as an answer. I get home, call a local boat repair, find out I can get in, in maybe 6 weeks. My fear is I am selling a good boat for cheap without the proper answers. So, I call a guy I know who is a car mechanic kind of friend and ask if he can run over and do a compression test. He pulls 2 plugs, says no way is this a compression issue,plugs show it is a too much gas issue! He also points out that the power is off, and the choke is open, and should be closed, and how much gas he can smell even though we never turned the boat on. He also checks the oil, and it is full and does not have gas in it, and we did not change it, so if it was a compression issue, it would not be full. The second plug was hard to get back in, so $60 paid. He leaves, saying he will come back later when Mr gets home and we are going to put it on water for him to test. He comes back, and talking, he discovers it has an electric fuel pump, which I thought he had seen earlier as he was listing all the new things he could see that were installed.He says he would guarantee it is the fuel pump pushing too much gas....talks about he thinks it causes the carburetor and plugs to foul out. He tells us we need to regulate the gas from the fuel pump. Says my Mr can buy and install anew fuel pump that is adjustable.
I've been on internet and can not find such a thing. He said another option would be to put a fuel flow regulator in there. In looking up Electric Fuel Pumps, we thought that we had discovered an issue. One we were looking at, marine said it was 2.5 - 4.5 psi. Our auto mechanic friend said a marine one should be 2-4 psi. But we ended up calling our local Marine part dept and found out that a mechanical one is 5-7 psi. Our boat does not call for an electric one, but if we were to get one they recommend a 8 psi. The one our boat has is an auto one, but has 9 psi.
We were thinking the next option would be to install an inline regulator and pressure gauge, but now are totally lost?
We do have an appointment with a Marine Dealer Repair Shop on July 5, but wanted to get the boat working and for sale before then.
I hope I explained this all enough for someone to help me. What do you all think???
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