Hello fellow boaters,
Boy do I have a predicament for y’all and I am looking for some Don S. Help. I have a 93 Glastron with a Volvo Penta aq131(red block color) coupled to the sp cd trim (290sp) outdrive. I have fully restored this boat myself but the trim gauge has never functioned which is frustrating. Originally the trim system was functional with gauge inop, so I replaced all the relays(OEM new), re wired the trim pump connectors as some wires had corrosion, replaced and indexed the trim sending unit. The trim system works as intended and trim and tilt functions are synchronized properly. The sender is a 3 wire sender, I do have the original but it functions the same. I have replaced the gauge, checked wiring to gauge which is not reversed or mis-wired. The gauge will initialize to full up when ignition is on but always reads above full up. The wires from the sender run straight into a larger harness that feeds into a trimmer control module Volvo p/n 857448 and then out to the gauge. I have tried replaced this module with the same results no matter what I try. The gauge operates perfect when hooked to gas gauge connector but will just not function when hooked to the trim module. The three leads coming out of the trimmer module are black (grnd), yellow(sending?) and purple (+12v). I get 2.1V constant between the yellow and black when ignition is on. I have cleaned all connections and I’m just at a loss. I have tested the gauge which reads a proper resistance, and when I connect a meter to the black/white wire from the sender and the green/white wire from the sender I get an alternating voltage from 1.8V(up)-3.8V(down) and an alternating voltage from 0V(down)-3.3V(up) on the green/white and black/white wires, this leads me to believe that the sending unit is working? I have even drawn a diagram of every wire and module in the trim system if that would help any of y’all understand my complete system better. I have verified all three trim sender wires make it from the sender connector all the way to the trimmer control module side of the connectors on the black trim module with no resistance. The trimmer control module has two set screws on the top for adjustment however I cannot find a manual for it anywhere and they are unmarked(I believe one screw sets the position of the upper trim range stop) and if I move the other screw it moves the needle on the gauge from full up to slightly below full up. The voltage during this screw adjustment is from 4.8v(above fill up) to I mainly want the gauge because while my trim range works and my upper tilt stop works automatically, I currently have no auto bottom stop in the trim range and it makes it hard to tell where the outdrive is when up in rpm and noise. I’ve heard there is an internal bypass in the trim pump that bypasses when the out drive is bottomed out however it makes a horrible screech and I’m not sure if there is supposed to be a auto bottom stop like at the top or not. Any help would be greatly appreciated!
thanks - Erik 20yr old newby
Boy do I have a predicament for y’all and I am looking for some Don S. Help. I have a 93 Glastron with a Volvo Penta aq131(red block color) coupled to the sp cd trim (290sp) outdrive. I have fully restored this boat myself but the trim gauge has never functioned which is frustrating. Originally the trim system was functional with gauge inop, so I replaced all the relays(OEM new), re wired the trim pump connectors as some wires had corrosion, replaced and indexed the trim sending unit. The trim system works as intended and trim and tilt functions are synchronized properly. The sender is a 3 wire sender, I do have the original but it functions the same. I have replaced the gauge, checked wiring to gauge which is not reversed or mis-wired. The gauge will initialize to full up when ignition is on but always reads above full up. The wires from the sender run straight into a larger harness that feeds into a trimmer control module Volvo p/n 857448 and then out to the gauge. I have tried replaced this module with the same results no matter what I try. The gauge operates perfect when hooked to gas gauge connector but will just not function when hooked to the trim module. The three leads coming out of the trimmer module are black (grnd), yellow(sending?) and purple (+12v). I get 2.1V constant between the yellow and black when ignition is on. I have cleaned all connections and I’m just at a loss. I have tested the gauge which reads a proper resistance, and when I connect a meter to the black/white wire from the sender and the green/white wire from the sender I get an alternating voltage from 1.8V(up)-3.8V(down) and an alternating voltage from 0V(down)-3.3V(up) on the green/white and black/white wires, this leads me to believe that the sending unit is working? I have even drawn a diagram of every wire and module in the trim system if that would help any of y’all understand my complete system better. I have verified all three trim sender wires make it from the sender connector all the way to the trimmer control module side of the connectors on the black trim module with no resistance. The trimmer control module has two set screws on the top for adjustment however I cannot find a manual for it anywhere and they are unmarked(I believe one screw sets the position of the upper trim range stop) and if I move the other screw it moves the needle on the gauge from full up to slightly below full up. The voltage during this screw adjustment is from 4.8v(above fill up) to I mainly want the gauge because while my trim range works and my upper tilt stop works automatically, I currently have no auto bottom stop in the trim range and it makes it hard to tell where the outdrive is when up in rpm and noise. I’ve heard there is an internal bypass in the trim pump that bypasses when the out drive is bottomed out however it makes a horrible screech and I’m not sure if there is supposed to be a auto bottom stop like at the top or not. Any help would be greatly appreciated!
thanks - Erik 20yr old newby
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