I bought an older pontoon houseboat and remodeled it in my yard. Took the late 80s model 75 hp mariner off and took it to a local boat shop. They went through the motor cleaned the carbs, installed new gas lines all the way through. Got it back at the last minute as the move was scheduled and due to the width of the boat it was a permit load. I bought one of the new plastic tanks that don't have the vent on the cap. The lines from the tank are a little over 6' long they also run through a fuel / water separator. Tank is about the same level as the motor but the separator is above the engine. Had a few hours to see if it would work. When I tried to fire it up it wouldn't start. Took an air line and pressurized the tank to force the gas all the way through the line as it took forever pumping the bulb. Motor finally started but would back fire almost like a sneeze. Loaded the boat as I was out of time and headed to the lake. Called the shop they said I might have to adjust the carbs a little.
Unloaded the boat it was a warm day, motor starts up and I drive to the marina where my boat is now docked. In the early morning hours if the boat starts I still get the "sneezing" backfire. Latter in the day after things warm up the boat will start and run OK. Not saying it runs great but will run and not backfire. Appears when the motor runs OK the new tank with out the vent has swelled some and there is pressure in the tank..
Now for the questions
Do I have too much gas line?
I've read this sneezing is due to the carbs not being adjusted correctly? I did see where this could cause major damage?
I'm not a great mechanic but could someone walk me through adjusting the carbs, even with a picture or too as I'm not clear on which screws are for which jets. I just don't have the money to sink into another boat mechanic and the boat is now 2 hours away from the first guy that got over $1000 to get the motor running.
I am 1 1/2 hours away from the boat so some questions you ask I may be able to answer right away if I know the answer but some I may have to get to the boat first. Thanks.
Any help would be appreciated
Unloaded the boat it was a warm day, motor starts up and I drive to the marina where my boat is now docked. In the early morning hours if the boat starts I still get the "sneezing" backfire. Latter in the day after things warm up the boat will start and run OK. Not saying it runs great but will run and not backfire. Appears when the motor runs OK the new tank with out the vent has swelled some and there is pressure in the tank..
Now for the questions
Do I have too much gas line?
I've read this sneezing is due to the carbs not being adjusted correctly? I did see where this could cause major damage?
I'm not a great mechanic but could someone walk me through adjusting the carbs, even with a picture or too as I'm not clear on which screws are for which jets. I just don't have the money to sink into another boat mechanic and the boat is now 2 hours away from the first guy that got over $1000 to get the motor running.
I am 1 1/2 hours away from the boat so some questions you ask I may be able to answer right away if I know the answer but some I may have to get to the boat first. Thanks.
Any help would be appreciated