SoCal Jet Boats

Tech Talk => Engine Mechanical / Electrical => Topic started by: JTMoney on August 21, 2011, 01:15:29 PM

Title: Seized olds
Post by: JTMoney on August 21, 2011, 01:15:29 PM
So my boat just died in the middle of the river and wouldn't start.  The starter engages but won't turn.  I was hoping the battery was just dead or worst case the jet seized because I need a new one anyways.  So I get home and meter the battery and it has 12 volts. I take a rachet and turn the motor back a little and try to start.  It turned to the point it was at before I turned it.  I disconnect the jet and that spins freely so obviously my motor is seized.  So what's the next step.  Is it as simple as new listing and a bore job or could it be the bottom end.  Where do u start to figure it out.  Also it was a great time at Big River this weekend.  You guys are really cool and I'm glad I joined the forum.
Title: Re: Seized olds
Post by: renegade on August 21, 2011, 01:52:53 PM
DID it seize while you were at full throttle? Pull the motor and pull the pan. check all mains and rod bearings.see if there is any metal shaveings in the oil. Could have to do alot of machine work on the crank and rods. sorry to here that! was there alot of hours on the engine?
Title: Re: Seized olds
Post by: Watts420 on August 21, 2011, 02:01:16 PM
Sorry to hear that.
Title: Re: Seized olds
Post by: JTMoney on August 21, 2011, 02:10:33 PM
It happened as I let off actually and as I was coming down to idle it just shut off.  Hrs I don't know.  The oil on the dip stick looks new but I haven't pumped It out yet.  I guess I need to get an engine hoist and start breaking it down.
Title: Re: Seized olds
Post by: Howard19 on August 21, 2011, 02:40:26 PM
1500 I have a motor that needs to be bored have the new pistons cam kit rings bearings also have a tunnul ram i have enough to biuld a 30 over motor pistons are keith black and crank if interested pm me your # I sold wollowwog his motor too
 


    Harry
Title: Re: Seized olds
Post by: IRRebel on August 21, 2011, 08:19:35 PM
Pull the spark plugs and see if water comes out when you try and turn it over.........Be my first thought on it. I didn't get a close look  at how you plumbed yours.

If no water, maybe broken timing chain and a lot lot else broke...... :banghead:

Ray
Title: Re: Seized olds
Post by: JTMoney on August 22, 2011, 06:01:31 PM
So I took the spark plugs out and all but one looked okay maybe a little lean.  I'm only saying that in comparison to dirt bike  plugs.  The one that wasn't okay was bent and some of the porcelain was broke off and now in that cylinder I imagine.  So eats the next starting point.
Title: Re: Seized olds
Post by: simidan on August 22, 2011, 06:25:36 PM
Did you try and turn the motor over with all the plugs out or just look at the plugs?
Title: Re: Seized olds
Post by: JTMoney on August 22, 2011, 06:37:37 PM
With all the plugs out.  It still won't budge
Title: Re: Seized olds
Post by: simidan on August 22, 2011, 06:58:24 PM
Sounds like your gonna have to start pulling covers. Bummer man. I just went through the same thing. Except I new right away what my problem was.

http://i66.photobucket.com/albums/h245/Chooch_album/Pump%20pics/DansphoneSept09012.jpg (http://i66.photobucket.com/albums/h245/Chooch_album/Pump%20pics/DansphoneSept09012.jpg)
Title: Re: Seized olds
Post by: IRRebel on August 22, 2011, 08:36:25 PM
Could be a few things JT, most of em pretty bad. Rule out the pump first though.

First things first, open up the handhole to the pump and look/feel around in there for something jamming the impeller. Look up through the rock grate as well.

Next I'd look closely at the driveline condition, and check that all the bolts are in place on the flywheel and in the driveline. If one of those backs out, could cause an issue.

Other than that, pull the engine or at least the heads and see whats up. If it's in the engine, I'd guess broken timing chain or cam and pistons are jammed against valves.

Ray
Title: Re: Seized olds
Post by: renegade on August 23, 2011, 11:03:41 AM
The spark plug with the damage is probably were the the piston hit it when the rod let go. PULL motor pull pan!! time for a fresh rebuild and then you will know what you got!
Title: Re: Seized olds
Post by: JTMoney on August 27, 2011, 07:40:15 PM
Well I pulled the motor and broke it down to find piston fragments everywhere.  The piston literally exploded.  And the corresponding rod bearing is non existent.  So in a round about way how much is this gonna cost me.
Title: Re: Seized olds
Post by: simidan on August 27, 2011, 07:54:22 PM
After new Hypertectic(sp) pistons w/old rods, comp cam, all new bearings, gaskets(duh), balancing and assembly, I was out just over $2k. That was the last motor. Nothin special. I dont know if thats a good deal or a rip off, but Im real happy with the engine thus far.

Now the new engine I have built in my head is another story. :screwy:
Title: Re: Seized olds
Post by: GlassCutter on August 27, 2011, 10:43:16 PM
It's gonna cost ya $4500.   Call Tom and buy the one that he listed here a few days ago . . .








before I have too.  :banghead:
Title: Re: Seized olds
Post by: Howard19 on August 28, 2011, 12:51:28 PM
LETS MAKE A DEAL i have what you need just shoot me a PM 8)
Title: Re: Seized olds
Post by: lobeeone on August 29, 2011, 02:51:03 PM
I have a 455 with a cracked block... Like 10-15 hours on motor, all internal are fine, good heads, edelbrock intake and carbs,  ran great... Found crack when I pulled motor to put in a new floor in boat. Carb to pan.
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