1992 OMC 5.0 (ford) cobra sezied will not turn over

dodge1971340

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Mar 23, 2006
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I have a stock 1992 caravelle 19' BR with OMC FORD 5.0 cobra (Ran Good)It was winterized, the outdrive is removed, it sat for a couple of years,will not turn over, I tryed to turn with a braker bar on crank, i removed the plugs sprayed PB blaster in the cylinders and let set for a couple of days with not even a budge . Maybe im overlooking something small can someone help me before i yank this thing out. I think the rings are sezied to the cyl walls really bad but it dosent hurt to ask before you jump in with both feet. Thanks all!! AND GOD BLESS!!!
 

Haut Medoc

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10,645
Re: 1992 OMC 5.0 (ford) cobra sezied will not turn over

With a siezed engine & no drive, I would start thinking about getting a different boat, preferably one that is not OMC ;) <br />Stick around though you'll get more feedback I'm sure.....JK
 

Mischief Managed

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Re: 1992 OMC 5.0 (ford) cobra sezied will not turn over

A half cup or so of Marvel Mystery oil in each cylinder for a few days should get it turning. Leave the plugs out to turn it though.
 

dodge1971340

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Re: 1992 OMC 5.0 (ford) cobra sezied will not turn over

Originally posted by Mischief Managed:<br /> A half cup or so of Marvel Mystery oil in each cylinder for a few days should get it turning. Leave the plugs out to turn it though.
Thanks i will try that first :)
 

dodge1971340

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Mar 23, 2006
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Re: 1992 OMC 5.0 (ford) cobra sezied will not turn over

Originally posted by Haut Medoc:<br /> With a siezed engine & no drive, I would start thinking about getting a different boat, preferably one that is not OMC ;) <br />Stick around though you'll get more feedback I'm sure.....JK
Yes im finding out OMC is$$$$ and :p :p :mad:
 

challenger

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Mar 12, 2006
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Re: 1992 OMC 5.0 (ford) cobra sezied will not turn over

I had that problem and found the alternator had froze and was preventing the motor from turning. I took off the belt and it turned freely.
 

Haut Medoc

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Re: 1992 OMC 5.0 (ford) cobra sezied will not turn over

Sorry, I didn't mean to discourage you....<br />It's just that you have a real uphill battle on your hands.....<br />Make sure the hull is worth the effort....<br />Do what MM suggests.....<br />The 302 Ford is a good motor....<br />That's what I have.......JK<br />It wouldn't hurt to try Shawn's suggestion either.....
 

dodge1971340

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Re: 1992 OMC 5.0 (ford) cobra sezied will not turn over

Originally posted by Haut Medoc:<br /> Sorry, I didn't mean to discourage you....<br />It's just that you have a real uphill battle on your hands.....<br />Make sure the hull is worth the effort....<br />Do what MM suggests.....<br />The 302 Ford is a good motor....<br />That's what I have.......JK<br />It wouldn't hurt to try Shawn's suggestion either.....
no apologies needed i was discouraged when i seen the drive was gone. yes its a big uphill because the hull is i great condition. mabey MM sugests will work its allredy soking. Thanks JK !!
 

dodge1971340

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Re: 1992 OMC 5.0 (ford) cobra sezied will not turn over

Originally posted by shawn Mahoney:<br /> I had that problem and found the alternator had froze and was preventing the motor from turning. I took off the belt and it turned freely.
Hi shawn thanks but alredy tryed that they were on there prity good ended up just cutting them off. Thanks GP
 

qaztwo

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Re: 1992 OMC 5.0 (ford) cobra sezied will not turn over

let the oil in cylinders sit for a few days if still no luck remove starter and use a pry bar to try a rotate the engine.
 

dodge1971340

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Re: 1992 OMC 5.0 (ford) cobra sezied will not turn over

HI guys. Thanks for all the help I tryed the myst oil and pry bar no luck i think if i keep prying im going end up braking something. Im just gona pull it, with the drive off its fairly easy, anyways i love wrenchen!! I well let you know the dianosess is. GP
 

dodge1971340

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Re: 1992 OMC 5.0 (ford) cobra sezied will not turn over

Hi Guys !! Got the motor pulled , The rings were sezed to the cyl walls prity good, but everything else looks good(visuly)Im going to rering it and y its down put new barrings in it, but there was alota moisture in the block from it setting so im going to have the heads and block looked at the machine shop just in case. There going to hone it for me y its there. Is there a way to check to see if the exaust man and rizers are leaking before i put this all back togeter. or if there is anything i should check before i put it back together it was winterized with antifreze and the moisture was clear water. Thanks!! GOOD DAY AND GOD BLESS!! Happy Easter!! GP
 

Haut Medoc

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Re: 1992 OMC 5.0 (ford) cobra sezied will not turn over

A visual inspection & a pressure test is about all you can do for the mans/risers.....JK
 

dodge1971340

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Re: 1992 OMC 5.0 (ford) cobra sezied will not turn over

Hi HM . I have a stupped ?? how do you block off the exit on the rizer to do a pressure check is there a trick! :confused: Thanks Good day and God bless GP
 

Reel Poor

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Jan 29, 2005
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Re: 1992 OMC 5.0 (ford) cobra sezied will not turn over

You could cut and fit a piece of plywood, then bolt the plywood on with some bolts and a piece of universal cork gasket between the wood and manifold.
 

Don S

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Re: 1992 OMC 5.0 (ford) cobra sezied will not turn over

Ok, that explains the end that bolts to the manifold.......... What do you do with the outlet end where the exhaust gas and water come together?
 

dodge1971340

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Re: 1992 OMC 5.0 (ford) cobra sezied will not turn over

Hi Guys!
thanks for all your help!!d:) I finaly got the motor back in, After to much time and money!!:^ LOL!! total rebuild and riz and mans. Ran it today for the first time everything looks good and sounds good .on the hoze!! Im going to lake test it some time this weekend. The only thing is the cobra has a inerupter switch and i wasnt sure if its sup to cut out when you go into gear or when coming out of gear when the prop has a load on it. i thought it was sup to to do it both ways but on the hose it it didnt do it eather way (But went into gear fer and rev) and the switch dose work i pushed on it, could it be the mouldule or dose it just need to be under load? Thanks again and God bless!! Dodge 8)
 

olbuddyjack

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Oct 23, 2003
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318
Re: 1992 OMC 5.0 (ford) cobra sezied will not turn over

It only works coming out of gear and under a load. You may have to put it in the water, under load for it to work properly.
 

Boatin Bob

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Sep 24, 2001
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Re: 1992 OMC 5.0 (ford) cobra sezied will not turn over

Hey Dodge...I'm a little confused, was your drive really missing when you bought the boat and did you pick up another one or was it just off and you've put it back on now?
 

dodge1971340

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Mar 23, 2006
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Re: 1992 OMC 5.0 (ford) cobra sezied will not turn over

Thanks Bud Jack. Thats what i thought just wasnt real sure if its was in and out. Bob The boat was bought threw Ebay and i learned my leson real quik never buy a boat with ot looking at it:%. I knew the motor was not running but the drive was included but when i picked up no drive said it was stolen. very unplesent experiance after that:'(. but i only payed $600. for it and the hull and inter in real good shape. i opt redoing, and as a mack i like to know what i have when i take it up to lake eire, I love redoing stuff, And with to much time and money im almost done.if the rain will hold off this weekend i would like to lake test it. I bought a used 4.3 outdrive and a 23 pitch prop to make up the gear rasheo. I Realy dont think the drive was stolen because the lock nuts were on the studs on the gimble. what theif is going to put the nuts back on when there in a hurry!! LOLo:) and i checked and surviced everything before i put the drive on. The thing that realy bums me and the kids out is that is that boatin season is almost over and my wife is obout ready to kill me if you see my face on a milk carton turn her in !!o:) LOL LOL.. Thanks again Dodge
 
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