96 Nautique will not start

Just purchased a 96 Nautique with a PCM 350. It was an out of state purchase from La.Got it yesterday. Anyway tried to start it today all I get is a chattering noise from the starter. The battery is dated 8/15. The previous owner hasn't been much help. This whole deal has been a nightmare from the start.

Can anyone tell me the rotation of this engine? I wanted to turn it over by hand a bit but wasn't sure of direction. Thanks.

A '96 should be LH rotation( CCW viewed from rear of engine).    If you roll it over with a wrench, it doesn't hurt it to turn backwards.

Assuming the battery is good, sounds like battery cable or connection problem. Check the ground connection on the engine too.

have you tested the battery voltage?

sounds like low voltage to me

Got it started. It was a bad cable connection where the cable attaches to the clamp. Thanks again for the help.
After running it I noticed the temp gauge is not working. I would guess it's the sending unit.
Can any one confirm the location? I'm pretty sure it's located fwd of eng. near the water pump. PCM 350.
Is it possible that the gauge could be bad?

The Battery is good. Although it looks like a Walmart batt. It's a Maxx Everstart 650CC Amp.
prob. OK for know since it's only a month old. Yes I agree new cables and ends. When I cut the end and stripped it there was still some rust showing. Time to replace. Size is #2. I will go to #1 maybe 1/0. As far as the gauge,I still have to do more checking. I did have 12v. at the gauge but when I shorted the sender wire it did not peg. I did not have time to check for continuity. I only ran the boat on the trailer for less that 10 min. The gauge never went higher than 120deg. With all the things I have been finding so far it wouldn't surprise me if he took the T-stat out.
I hope to get it out on the water maybe this weekend. If there is no shaft vibration I'll be happy. The other issues are nothing.

The big question is why I bought it without actually seeing it. There are a lot more boats down south than up in the North east. I was stuck on that color combination and year. The price was where I wanted to be also.

Ok hear we go. I had the battery cable issue resolved for now. Last night I turned the motor over it started no prob. Today i got home from work I decided to start it again because I planned to drop it in the lake tomorrow to ckeck the running gear. Hit the ignition, nothing.
The volt gauge shows nothing the Tach pegged out the ignition light and the trouble light were dim. I put my volt meter across the battery and got 12.5V. Even when I go to start.
The only thing I didn't mention is I had a battery tendender connected when i tried to start.

Yes I did. What bothers me is that the gauges and the lights went bull***************. Oh BTW the neutral switch was bypassed by the previous owner.

but if you measure while cranking you should see if it drops, anything below 10 and you will have issues.

Also, check if you are getting 12v on the starter solenoid, if you do then check if your solenoid is actually closing, can do a continuity test on the solenoid contacts going to the starter motor. or just check voltage there when you crank, should get 12 again as it closes the circuit.

Battery load tested good. Cables were bad. Thanks again for the help. This site is priceless.

The gauge is ok must be the sending unit. I can't belive they mounted under the t-stat
housing with a 1/4" of space.

I grounded the sender wire at the engine and the gauge pegged. So I would say that rules out the gauge.