96 xp won’t crank with plugs

[J_loughman]

I have a 1996 seadoo xp with the 787. Was towed in last ride due to a dead battery. Replaced the battery and the motor was locked up. Broke it free with channel locks on the drive shaft. Checked compression and both cylinders are 150. Engine cranks over good without the plugs in and no water comes out so don’t believe there is any water in the motor. When the plugs are in and trying to start it up it only cranks about a 1/4 turn and gets stuck. Replaced the starter as it was the original, thinking maybe it was too weak to crank the motor under compression, and still only turns a 1/4 crank and stops with the new starter. What could the issue be?

 

[rusty nail]

bridge the solenoid with insulated pliers or screw driver. if the starter runs strong the solenoid is starting to go bad.

 

[rusty nail]

wierd that you say it gets stuck....without the plugs in can you grab the pto/driveshaft with just your hand and see if it turns smoothly? you should not feel any sticking.

 

[J_loughman]

wierd that you say it gets stuck....without the plugs in can you grab the pto/driveshaft with just your hand and see if it turns smoothly? you should not feel any sticking.

Yes with no plugs in the motor can be turned by hand

 

[rusty nail]

try testing your solenoid

 

[banker505]

I had that starting problem also. Replace starter but it turned out to bad ground and positive cables.

 

[mikidymac]

Jumping the solenoid will tell you if it is the cables and starter.

 

['07 Challenger]

I have a 1996 seadoo xp with the 787. Was towed in last ride due to a dead battery. Replaced the battery and the motor was locked up. Broke it free with channel locks on the drive shaft.

Something obviously went wrong since the engine was seized, whatever that was could be causing the no-crank problem. What killed the first battery, and did you get it tested to know that it was truly dead, or assumed it was dead because it wouldn't crank?

 

[DoxieXP]

Something obviously went wrong since the engine was seized, whatever that was could be causing the no-crank problem. What killed the first battery, and did you get it tested to know that it was truly dead, or assumed it was dead because it wouldn't crank?

My 95 717 do is great but…

I’m having the same problem with a non Seadoo. The starter could spin it without plugs but couldn’t spin it with them in. Now I can’t turn it by hand anymore.

 

[chando]

Hello colleagues, I am writing from Bulgaria, I have the same problem, the engine has not been started for 5 years, without spark plugs, the engine runs perfectly when cranked by hand, no problem is felt, but with spark plugs, it cranks only 1.4 quarters, I applied current directly to the starter

 

['07 Challenger]

What are you using to apply power to the starter?

 

[chando]

What are you using to apply power to the starter?

Battery from a car, I supply current with thick cables directly to the starter

 

['07 Challenger]

It might be because of the cables, assuming you mean jumper cables and not battery cables with terminals that are bolted onto the ski. The contact area of the clamps may not be able to pass enough power, especially with steel clamps which are common. Also, many jumper cables are deceptively thick on the outside with thin wires. Depending on the length of the cables they may need to be one or more steps thicker gauge than the stock cables to be able to pass the same amount of current.

The vast majority of jumper cables have excess insulation to fool people into thinking it's a thick wire. I've seen some that look like 4 ga. on the outside and have 14ga wire in them. To make it worse, many use aluminum wire instead of copper which will pass less current for a given size.

I have 1ga. cables with copper clamps and even those will have trouble passing enough current to effectively crank something that doesn't have a battery.

If you have a voltmeter you can check to see if you're passing enough power to the starter. Put the meter on the battery posts, not touching the clamps, and crank, see what the voltage drops down to. Then move the meter leads to the starter post and engine case ground and see what voltage you get there. The meter leads need to be on the ski parts and not touching the jumper cable clamps. I expect that you'll see very little drop at the battery and a huge drop at the ski. If it's a good battery and the voltage drops more than 3v at the battery you either have a bad starter or an engine problem. I expect you'll see around 1-2v. at most.

 

[chando]

The cables are real original, ok tomorrow I will measure the battery current drop