I have leaky carb bowls in my 89 OMC Seadrive 140. I tried to follow some others advice and sand the bowls down, but I am not sure if I sanded enough.
On my bowls they had a small ridge (lip) on the gasket surface that ran around the entire bowl, I was afraid if I sanded too much I would lose this lip and make things worse, so I only sanded for a minute or so, with the 400 grit sandpaper taped to a glass table moving the carb bowls in a figure 8 pattern. It was difficult to see whether the bowls were warped and any difference after sanding because of this lip. I basically sanded until I could see the sand marks all around the lip and a little on the outer edge of each mounting ear.
I then rebuilt the carbs and reassembled trying not to tighten the bowls too tightly, since someone suggested that this is why they warp.
When I put the carbs back on, they still leaked when primed. So I took them off one at a time, tightened them some more, and put them back in place with just one bolt hand tightened so I could pump the primer again. Tightening the bowls seemed to stop the leak while the carb was loosely mounted with the one bolt, however once I fully remounted the carbs to the throttle body and torqued the bolts, the leaks seemed to get worse, almost as if the pressure of the bottom two bolts, was warping the bowls and/or the carb body. I backed off the torque from 120 to 90, and the leak slowed down to a very slow drip.
I took the boat to the lake for a water test I could not get up on plane.
Assuming that the carbs were sucking air, should I take the carbs off again and sand the bowls completely flat removing the lip?
I could order new bowls, but I read they never made aluminum bowls for the looper carbs, so I would be getting the same plastic bowls and may have the same issue down the road. Plus, I am not sure that the carb bodies are not also contributing to the problem.
Is there an aluminum carb from another year that I can use?
On my bowls they had a small ridge (lip) on the gasket surface that ran around the entire bowl, I was afraid if I sanded too much I would lose this lip and make things worse, so I only sanded for a minute or so, with the 400 grit sandpaper taped to a glass table moving the carb bowls in a figure 8 pattern. It was difficult to see whether the bowls were warped and any difference after sanding because of this lip. I basically sanded until I could see the sand marks all around the lip and a little on the outer edge of each mounting ear.
I then rebuilt the carbs and reassembled trying not to tighten the bowls too tightly, since someone suggested that this is why they warp.
When I put the carbs back on, they still leaked when primed. So I took them off one at a time, tightened them some more, and put them back in place with just one bolt hand tightened so I could pump the primer again. Tightening the bowls seemed to stop the leak while the carb was loosely mounted with the one bolt, however once I fully remounted the carbs to the throttle body and torqued the bolts, the leaks seemed to get worse, almost as if the pressure of the bottom two bolts, was warping the bowls and/or the carb body. I backed off the torque from 120 to 90, and the leak slowed down to a very slow drip.
I took the boat to the lake for a water test I could not get up on plane.
Assuming that the carbs were sucking air, should I take the carbs off again and sand the bowls completely flat removing the lip?
I could order new bowls, but I read they never made aluminum bowls for the looper carbs, so I would be getting the same plastic bowls and may have the same issue down the road. Plus, I am not sure that the carb bodies are not also contributing to the problem.
Is there an aluminum carb from another year that I can use?