siezed engine??

[loner]

I got my boat out of shed to work on the other day, went to start her and flat battery, so I replaced battery. then I went to start her and clunk no turn over, so I pulled starter motor thinking that it was siezed but no it seams to work fine with a pair of jumper leads. so then I tried to turn motor by hand(breaker bar and socket) I could not even budge it. :???:

can the prop shaft sieze up or is the engine buggered.

its a pro boss 93 nautique. keep in mind that I'm in Oz and don't need to winterize etc. hasn't been used for about 6 months.

please help

[Andrew]

RE: siezed engine??

unless it is in gear, the prop shaft won't affect the rotation of the engine. i'm not gonna say that it is seized, but it doesn't sond promising........

[boatech]

RE: siezed engine??

pull the plugs take a look for anything out of the norm and see if you can turn it over by hand and pay attention to what comes out of the cyls.

[loner]

I didn't think that the propshaft would make a dif if in neutral. guess I was just hoping for a simple solution. I will remove plugs and have a look but if you have a suggestion about turning engine manually then I'm open because I could not do it when I tried. pehaps a bigger peice of tube on the rachet would do it.

[Andrew]

spray a liberal amount of wd-40 through the spark plug holes and let it sit over night. this should break down any rust that could prevent the cylinders from moving. after about 12 hours, try and rotate it by hand again.

[TRBenj]

I find it very odd that the engine seized after only 6 months of inactivity- especially an engine this new. Shoot some penetrating oil up the spark plug holes several times over the span of a few days. Get a longer breaker bar on there and it should break free.

[M3Fan]

While we are on the subject- what is the proper procedure for manually turning an engine over? Breaker bar with a socket on the bolt which holds the crank pulley? Can you spin that pulley by hand if the plugs are out and the accessory belts are off? How much harder should the pulley be to turn by hand with the plugs in?

[06210rider]

With the plugs out you should be able to turn it over by hand, if you can do it with the plugs in; you are He Man and I want your autograph.

[surroundsound64]

I'd recommend using Marvel Mystery Oil in the cylinders. It does a number of things that other products, such as wd-40, don't. I usually spray it in my cylinders each winter when I winterize it and put a quart in the oil as well.

[TRBenj]

While we are on the subject- what is the proper procedure for manually turning an engine over? Breaker bar with a socket on the bolt which holds the crank pulley? Can you spin that pulley by hand if the plugs are out and the accessory belts are off? How much harder should the pulley be to turn by hand with the plugs in?

You got it- breaker bar on the crank pulley bolt.

Its definitely not possible to turn the pully without a bar with the plugs in- and I bet its pretty tough even with the plugs out. We used a breaker bar to turn the crank while degreeing the cam, heads were off at that point.

[M3Fan]

This is the first year I actually sprayed fogging oil into the cylinders (dry intake) and I certainly had no breaker bar in my tool inventory, so I tried to he-man the crank pulley just to turn the engine over- I'll say I did get the crank around a couple degrees- maybe a quarter of the way, but it took an extrordinary amount of effort with the plugs in. I felt like an idiot doing it, but it was the end of a long day and I had already put the plugs back in. If there was a video of me trying to turn that thing, it would have been hilarious.

[mdboats]

Seized engine??

Are you sure the starter is fine? Make sure the starter drive (bendix) is engaging and not spinning in place. Make sure you have 12v at the starter.

If the motor ran six months a go and ran fine, what would cause this motor to sieze in this short time period. Something does not calculate here.

If you are worried about the motor being locked up, take the plugs out and use the breaker bar to spin the engine. It is hard to spin but not outrageous. If it does not want to spin QUIT, go no further. If it does spin then check your electronics (voltage) to starter.

Good luck.

Mark Q

[boatech]

RE: Seized engine??

doing it with plugs in is tougher but can be done i do it all the time. it is much easier with the plugs out it should take very little effort. socket on center crank bolt an breaker bar are the tools used. marvel mystery oil is a good suggestion.

[loner]

thanks guys for the input. I too have previously turned the crank shaft with the plugs in admittedly it wasn't easy but could be done. I will try the wd-40(crc) approach and try to turn engine with spark plugs out. I have gone many a winter without cranking the engine. There is no sign of water in sump oil or anything that would suggest engine would/could be seize.

[nch20skier]

Marvel Mystery Oil

:arrow: I agree with souroundski and others. The mystery oil has always worked wonders. When I winterize my boat I actually use about 2 tablespoons down each cylinder. I also have a '56 Chris Craft that has been idle for 15+ years and the engine remains free thanks to the mystery oil (I suspect).
Good luck!