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wrxspitfire
08-02-2007, 11:49 PM
I have an 86 prostar with a 351. After running around for an hour or two then stopping the Engine wont turn over to start. After getting a tow back to the landing and driving home the boat started right up on the trailer. It is not a fuel problem. I have already replaced the battery and the starter.

Does anyone have any ideas. Please help.

Hoosier Bob
08-02-2007, 11:59 PM
Nuetral switch? Anytime this happens try moving the throttle back and fourth. I had a similar situation with an older *********** that I had in the day. Morse Control of course.

wrxspitfire
08-04-2007, 08:59 AM
This is not it. The starter does ingage, but acts like it does not have enough juice to turn over the motor. But once engine is cold down, All is well again.

I have not taken reading on voltage so could it be that the battery is just not getting chaged fro the altenator. What should the alt meter read while engine is running? Mine reads just above positive while running.

6ballsisall
08-04-2007, 09:06 AM
I had an 86' that did this too. I ended up having to replace several starter solenoids which are located on a plate above the transmission. Later on I replaced the starter with one of those newer style 351W starters (great investment) and the problem was solved. Those 351W need a lot of motor to get them turned over.

bigmac
08-04-2007, 09:10 AM
This is not it. The starter does ingage, but acts like it does not have enough juice to turn over the motor. But once engine is cold down, All is well again.

I have not taken reading on voltage so could it be that the battery is just not getting chaged fro the altenator. What should the alt meter read while engine is running? Mine reads just above positive while running.

If the battery weren't getting charged, I wouldn't think it would start on the trailer either.

My guess is electrical connection or dying starter or solenoid. Check and clean the battery terminals and all connections in the primary circuit (all the big wires). Make sure all the grounds are good. If that doesn't do it, pull the starter and take it to some auto store than can check it.

If you end up needing a new starter, call SkiDim. The temptation might be to get an automotive starter, but you need a marine-grade version.

JimN
08-04-2007, 09:46 AM
wrx- make sure the starter mating surface on the motor is clean, the solenoid base plate is grounded and the grounds on the block are clean and tight. Go back and re-tighten the starter bolts. If you can duplicate the problem this weekend, put a voltmeter on the battery + and - terminals to see the voltage while cranking when it won't start. Check it before to have a reference. If it drops significantly more when it's hot, you may have a bad starter, or it may have been cranked for too long and the armature is damaged. IF you can, remove the new starter while it's still hot and take it to the place where you bought it to have it tested (if they test), or wherever it can be tested. Heating it up isn't something they can do, though.


Could be a few things but they all need to be checked.

jlf
08-04-2007, 11:11 AM
Had similar situation on my buddies boat. He replaced batt. alt. and starter. still no fix. I did a voltage drop test on battery cables and found both battery cables bad. As heat increases resistance increases. Something easy to check. Wouldnt rule out the starter though.

Bert
08-04-2007, 11:11 AM
I have an 86 prostar with a 351. After running around for an hour or two then stopping the Engine wont turn over to start. After getting a tow back to the landing and driving home the boat started right up on the trailer. It is not a fuel problem. I have already replaced the battery and the starter.

Does anyone have any ideas. Please help.
What kind of battery do you have ? When my boat was brand new it did that. I would get towed in and teased about the "Mastercrap"::o

Replaced the marine battery. Still did it. Dealer sent me a new starter. It still did it. Threw out the marine battery and put in an automotive battery. Never had another problem for the past 14 years but I have a spare starter and I have towed a few in:)

JimN
08-04-2007, 11:17 AM
If the 'Marine" battery was a deep cycle battery, that would explain it. Deep cycle batteries aren't for instantaneous high current use, they're for reserve power.

Bert
08-04-2007, 11:34 AM
If the 'Marine" battery was a deep cycle battery, that would explain it. Deep cycle batteries aren't for instantaneous high current use, they're for reserve power.
Yep, some times the wrong battery for the application get's installed. In my case the marine battery was claimed to be 650 CCA but I don't believe it was.

Commandohorn
08-07-2007, 02:11 PM
I just went through this exact senario, look for the thread under my name, check the voltage at the starter when it engages, if it drops below 12V your starter is bad.



This is not it. The starter does ingage, but acts like it does not have enough juice to turn over the motor. But once engine is cold down, All is well again.

I have not taken reading on voltage so could it be that the battery is just not getting chaged fro the altenator. What should the alt meter read while engine is running? Mine reads just above positive while running.

wesgardner
08-07-2007, 02:21 PM
I went thru the entire ill-starting scenario with a boat about the age of yours - long story short - the "S" terminal wire from the solenoid up to the key switch and back to the battery was bad/undersized from the factory/corroded/whatever...rewired with 10 ga. - all is well - no more eating thru solenoids, no more weak starting. So...you can re-wire your ignition circuit - takes about 2 hours, have your starter rebuilt - due to low-voltage/heat, it may be toast by now, make sure all wiring is GOOD - not just looks good but IS good.

I surely wish someone had told me to do this in the beginning as it would have saved many hours of anguish - if you're experiencing sluggish starting it's two things - the starter/solenoid and/or wiring - in an old boat, just renew it and move on - you can do the DUI distributor deal if you want.

Remember, a solenoid does two things - it engages the pinion gear (often times called Bendix) as well as acts like a relay for the actual starter motor...ALL wiring has to be GOOD or you won't get hot starts....

wrxspitfire
08-13-2007, 11:13 PM
I wet out and bought a 1100 CA battery. While at the store I also picked up a new coil. I installed both and cleaned all th terminals in the starter circuit. Boy what a difference. Boat starts with just a nip of the key. I wish I would have done this at the beginning of the season. Well worth it.

Thanks all for the suggestions.

Kevin 89MC
08-14-2007, 11:20 AM
I wet out and bought a 1100 CA battery. While at the store I also picked up a new coil. I installed both and cleaned all th terminals in the starter circuit. Boy what a difference. Boat starts with just a nip of the key. I wish I would have done this at the beginning of the season. Well worth it.

Thanks all for the suggestions.
Great! I was just going to add that I also had the same trouble as you a few years ago. I switched from a marine battery to a regular car battery, it solved my problem and it has been starting perfect for 2 years.
Kevin

JimN
08-14-2007, 01:40 PM
IIRC, the issue of which type of battery has been bludgeoned to death here and on other forums. A marine reserve battery, AKA deep cycle, is not made for cranking a car/truck motor. It's for supplying power to accessories. It may work for a small-ish outboard motor, but it's for reserve power, nothing more. A car battery is for cranking a motor and supplying instantaneous current and voltage.

I though this was also covered in the FAQ and search sections (it is). Someone, like the moderators, need to post some sticky threads about where to look for specific issues and organize it so it's a no-brainer for new people to use.

I have seen more threads, lately, about things that have been beaten to a pulp in years passed. Fuel and cranking issues should be available in easily found folders, broken down into boat model and year. They need to be segregated more, so wading through every thread isn't necessary. Also, a sticky should be on all forum pages to remind people to use the search function first.