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View Full Version : Mechanical help..strange issue..


Commandohorn
07-20-2007, 09:35 AM
My 88 Tristar stranded me on the lake last night. I have been having what I thought were charging issues, and the battery is brand new. I get 13.8 volts will running at 1500 RPM, so I figure alternator is OK. All connections were cleaned. Here is the scenario and what I think is going on. Boat cranks great cold. Run it for 10 minutes and then do one slalom run, she's good and hot now. Turn it off maybe 5 minutes. Try to start it again and it barely turns over and will not crank, like the battery has died! Had freshly charged spare, hooked it up, same result, barely turning over. Leave it over night, this AM she cranks right up. I'm thinking it is the starter selenoid now, flaking out when it gets hot! Any opinions? How do you test the selenoid? Please help me avoid a visit to the stealership! I do all the maintenance, and have all the tools. Thanks!

pilot02
07-20-2007, 10:04 AM
My bet's starter.
I have an 89 and I've had to get my starter rebuilt twice over the past several years for the same problem. When the engine (and starter) are hot, the resistance through the winding's is greater requiring more energy through the circuit.
Each time this has occurred, I've taken the starter in, had it rebuilt and the problem's gone for another couple years.

NeilM
07-20-2007, 10:18 AM
I agree. Assuming you've done the standard "check all connections are tight and corrosion-free" thing, the starter is the next-most-likely suspect.

cwright
07-20-2007, 11:15 AM
I just lived through this problem. Based on my lessons learned, if confronted with your symptoms, the first thing I would do is get out my multi tester and confirm I'm getting 12 volts going into to the selonoid, and 12 volts coming out. If ok, I would then test resistance on the lead from selonoid to the starter. Mine was bad and caused your symptoms. If lead is good, or replacing it doesn't eliminate your problem, I would pull starter, (takes about 5 minutes) and go to a shop that can test for excessive amp draw. I'm specualting a bit here, but I believe the amp draw goes up with temp, so it may start fine cold, but once hot, some internal clearnace may be gone and is causing some shorts or arc internal to the starter and is creating a big amp draw when trying to crank. This sucks down your voltage and has a double negative in that it cranks your engine slow, and produces a weak spark from the coil. Also, never trust your dash guage as a diagnostic device, they are predicatbly inaccurate. Good luck and let us know what you find out.

Commandohorn
07-20-2007, 11:31 AM
Thanks for the input. Further research tells me it is not the solenoid, if the starter turns, it's working. I'll check for voltage along the whole path. Skidim has my starter for $200. I'd pay that in a heartbeat to avoid a repeat of last night! Maybe I'll get lucky and find the problem in a cable. I had already disconnected and cleaned all cables, but did not do a resistance check.






I just lived through this problem. Based on my lessons learned, if confronted with your symptoms, the first thing I would do is get out my multi tester and confirm I'm getting 12 volts going into to the selonoid, and 12 volts coming out. If ok, I would then test resistance on the lead from selonoid to the starter. Mine was bad and caused your symptoms. If lead is good, or replacing it doesn't eliminate your problem, I would pull starter, (takes about 5 minutes) and go to a shop that can test for excessive amp draw. I'm specualting a bit here, but I believe the amp draw goes up with temp, so it may start fine cold, but once hot, some internal clearnace may be gone and is causing some shorts or arc internal to the starter and is creating a big amp draw when trying to crank. This sucks down your voltage and has a double negative in that it cranks your engine slow, and produces a weak spark from the coil. Also, never trust your dash guage as a diagnostic device, they are predicatbly inaccurate. Good luck and let us know what you find out.

cwright
07-20-2007, 09:03 PM
I just had mine rebuilt for $85. Better than 200 I figure. The starter can turn but draw too many amps. A two person test is to put your multi tester on the starter lead that the last cable is bolted to, and wee what kind of voltage you are registering there while cranking. I'm not sure how much drop you should expect, but I knew I was in trouble when my starter (that turned) was only getting 5 volts while engaged. A turning starter could still be drawing too many amps and kill your voltage. Good luck

rektek
07-22-2007, 01:22 AM
Commando,
sounds like starter to me, but I'd be doing some voltage drop tests and starter draw tests before dropping cash on a guess repair.
you'll need a multimeter for the voltage drop tests and a amp clamp for the starter draw tests. let me know if you need some help

cheers
jeff

Commandohorn
07-22-2007, 07:10 AM
Update...When cranking, the voltage would drop below 10V at the starter and selenoid so I have been checking for 12V from the battery back to the switch and found that I'm getting 12V through the circuit breaker and all the way back to the ignition switch....so....yep, it's the starter. At least I saved myself a a lot of $$ at $40 per hour at the stealership. Starter is probably 5 years old, thought it would last more than that...oh well. So the moral of the story is...if you crank OK cold, then crank too slow to fire when hot then it's starter time! If you have read this far I have just saved you a lot of time and money!

Leroy
07-22-2007, 09:05 AM
Good news! I've heard this same condition many times and it always seems to be the starter.