Having issues, lost 15 mph
08-04-2020, 03:20 PM
#1
Registered
Thread Starter
Having issues, lost 15 mph
Hey guys, i have a 1988 scarab excel 28 single engine 454/bravo one.
this is kind of a long story but if you have time to read and give your input it would be appreciated.
Ive had the boat since this summer, had it in and out of the water at first because i would do some repairs during the week and ride it in the weekends.
Was descent performer managed a best top speed of 57mph with a 23p 3blade mirage plus prop at 4800 rpm. would do 55mph witouth fuss.
I notice it was taking in water from the exhaust Y pipe during a engine test in my driveway. I took the boat 1 last time on the lake to check out if the powersteering pump i had changed was good.
while on that run the bilgepump hose cracked and when it was ready to pump out it blew water all over the engine bay. especially the area where the engine harness and boat harness come together on crimped ends and are screw on a connecting board.
i manage to plug the hose back and all was good for that ride.
brought it to my marinas boat shop and had them check my Y pipe because i dont have the equipement to pull the engine. Overall the boat stayed sitting for 2 weeks.
The Y pipe wasnt cracked but simply loose, the seal was changed and the engine coupler also while the engine was out. I was a happy man ready for my vacations
Here is where the new issues occur.
i put the boat in the water and it wont start, i think to myself when was the last time i charged the batteries? 2 weeks isnt enought to kill them but w/e i have the boosterpack handy lets get it done.
i open the hatch crank crank crank some comes out of some wires, its the groud wire to the thunderbolt ignition module that is overheating and melting WTF(its relocated on the transom, not bolted to manifolds)
I check the batterie posts and the ground is loose as in unscrewed. pull on the positive it comes off, wtf it just came out of the shop and the mecanic actually fires it to test the leak so i dont understanbd wats going on, anyways i bolt everything back tight finally fire the engine. it runs.
i make my way off the ramp idleing, all my gages are going crazy, the boat keeps dieing i painfully make it back to my dock witch is about 1/2 mile away.
i replaced the melted ground wire and doubled the gage( note the cable itself wasnt melted just part of the insulation)
then i noticed all the connection on my conection bar are green/corroded from the water. i call it a day and leave the boat at the dock for the night il clean the connections tomorow.
the next morning i get to unscrewing all the connection leads cleaning them with scotchbright pad.
the engine fire up seems pretty stable, had my batteries charged up over night so that eliminates them being part of the issue.
Boat starts but the gages dont stutter as much, i go for a test run. it runs but sometimes i loose all the gages for half a second and the engine missfires at the same time, them everything comesback real quick or if im not lucky the bots looses all power and shuts off.
alternator gives me a solid 14,8v, cleaned the wire leads with scotchbrightpad even tough it wasnt corroded, redid all the crimp connections the i had previously cleaned with new crimps on clean wire, pulled a new ground wire from batterie post to front pannel main ground lead.
the front main fuse panel gives me 13.7 with engine idleing and my gages dont stutter anymore appart from the Stock voltmeter. i used 2 sets of booster cables to mimmic my ground wires in the engine bay to makle sure i wasnt missing anything and i didnt noce a difference with or witouth the booster cables as added grounds.
the boat kinda handles normally now appart from the voltmeter gage, and the speed, cuz trough all the gremmlins i was chassing and doind my test runs i didnt realize the boat wasnt going pass 40ish mph.
when i give it throttle everything seem normal till 3800 rpm where im riding at 40ish then when i give it more it barrely makes it pass 4100rpm and 44mph at wot.
the boat has been sleeping at the docks since and i notice it has a lean to it, there is no water in the bilge but i keep wondering if its full of water and cant pull its weight. the top part where the batterie sit has no drain and is closed. these boat do have 3 drain plugs in the back( 1 on each swimdeck sides) will be pulling the boat out this weekend to make sure no water is in those swimdeck drainplugs.
my other idea is maybe the timing doesnt get advanced, is this controlled by the igniton module or is it weights in the ditributor?
or i didnt find the loose or corroded wire i need to find.
cant beleive i just wrote all this crap sorry i made it so long and its probably all mixed up but i wanted to putas much info on wat happened fore and afther and hopefully i can fix this beast and have her running great again.
this is kind of a long story but if you have time to read and give your input it would be appreciated.
Ive had the boat since this summer, had it in and out of the water at first because i would do some repairs during the week and ride it in the weekends.
Was descent performer managed a best top speed of 57mph with a 23p 3blade mirage plus prop at 4800 rpm. would do 55mph witouth fuss.
I notice it was taking in water from the exhaust Y pipe during a engine test in my driveway. I took the boat 1 last time on the lake to check out if the powersteering pump i had changed was good.
while on that run the bilgepump hose cracked and when it was ready to pump out it blew water all over the engine bay. especially the area where the engine harness and boat harness come together on crimped ends and are screw on a connecting board.
i manage to plug the hose back and all was good for that ride.
brought it to my marinas boat shop and had them check my Y pipe because i dont have the equipement to pull the engine. Overall the boat stayed sitting for 2 weeks.
The Y pipe wasnt cracked but simply loose, the seal was changed and the engine coupler also while the engine was out. I was a happy man ready for my vacations
Here is where the new issues occur.
i put the boat in the water and it wont start, i think to myself when was the last time i charged the batteries? 2 weeks isnt enought to kill them but w/e i have the boosterpack handy lets get it done.
i open the hatch crank crank crank some comes out of some wires, its the groud wire to the thunderbolt ignition module that is overheating and melting WTF(its relocated on the transom, not bolted to manifolds)
I check the batterie posts and the ground is loose as in unscrewed. pull on the positive it comes off, wtf it just came out of the shop and the mecanic actually fires it to test the leak so i dont understanbd wats going on, anyways i bolt everything back tight finally fire the engine. it runs.
i make my way off the ramp idleing, all my gages are going crazy, the boat keeps dieing i painfully make it back to my dock witch is about 1/2 mile away.
i replaced the melted ground wire and doubled the gage( note the cable itself wasnt melted just part of the insulation)
then i noticed all the connection on my conection bar are green/corroded from the water. i call it a day and leave the boat at the dock for the night il clean the connections tomorow.
the next morning i get to unscrewing all the connection leads cleaning them with scotchbright pad.
the engine fire up seems pretty stable, had my batteries charged up over night so that eliminates them being part of the issue.
Boat starts but the gages dont stutter as much, i go for a test run. it runs but sometimes i loose all the gages for half a second and the engine missfires at the same time, them everything comesback real quick or if im not lucky the bots looses all power and shuts off.
alternator gives me a solid 14,8v, cleaned the wire leads with scotchbrightpad even tough it wasnt corroded, redid all the crimp connections the i had previously cleaned with new crimps on clean wire, pulled a new ground wire from batterie post to front pannel main ground lead.
the front main fuse panel gives me 13.7 with engine idleing and my gages dont stutter anymore appart from the Stock voltmeter. i used 2 sets of booster cables to mimmic my ground wires in the engine bay to makle sure i wasnt missing anything and i didnt noce a difference with or witouth the booster cables as added grounds.
the boat kinda handles normally now appart from the voltmeter gage, and the speed, cuz trough all the gremmlins i was chassing and doind my test runs i didnt realize the boat wasnt going pass 40ish mph.
when i give it throttle everything seem normal till 3800 rpm where im riding at 40ish then when i give it more it barrely makes it pass 4100rpm and 44mph at wot.
the boat has been sleeping at the docks since and i notice it has a lean to it, there is no water in the bilge but i keep wondering if its full of water and cant pull its weight. the top part where the batterie sit has no drain and is closed. these boat do have 3 drain plugs in the back( 1 on each swimdeck sides) will be pulling the boat out this weekend to make sure no water is in those swimdeck drainplugs.
my other idea is maybe the timing doesnt get advanced, is this controlled by the igniton module or is it weights in the ditributor?
or i didnt find the loose or corroded wire i need to find.
cant beleive i just wrote all this crap sorry i made it so long and its probably all mixed up but i wanted to putas much info on wat happened fore and afther and hopefully i can fix this beast and have her running great again.
