1980 OMC 230hp 350 question.

[doberman-guy]

My engine is foze and getting ready to pull the heads off. I've tried pb blaster, and I've tried tranny fluid in the cylinders. I can only get it to move an 1/8 of an inch either way. I have a nylon rope wrapped around the pully and hooked up to a hand cranked wench. It would be like i am trying to pull start it and i also tried to turn it from the nut, but its only a 5/8ths nut and i dont want to stip it. Sorry for dragging out the question, i just wanted you the reader to see all i have tried. My question is if i cant unfreeze this engine can I call a junk yard and replace this with another 1980 350, or what am i looking to ask for? I will use all the external parts from this engine for the other. Also is there anything i have not tried yet to unfreeze this engine before i remove the heads? Thank you for taking time to read all this.

 

[drem312]

Re: 1980 OMC 230hp 350 question.

Are you doing this with the drive off? The reason is to eliminate any chance the outdrive is the problem

 

[doberman-guy]

Re: 1980 OMC 230hp 350 question.

When you ask if drive is off, are you asking if its in nuetral? If so, yes it is i can turn the key and the starter will engage. If im not getting the question please inform me. thanks

 

[Gettinther]

Re: 1980 OMC 230hp 350 question.

When you ask if drive is off, are you asking if its in nuetral? If so, yes it is i can turn the key and the starter will engage. If im not getting the question please inform me. thanks

Is the outdrive removed from the boat? If it is still on the boat it may be the drive that is siezed not the engine . Or how do you know its the engine thats siezed???

YOUR question is if i cant unfreeze this engine can I call a junk yard and replace this with another 1980 350
Yes you can, just remember to change over all marine equipment internally and externally, internally there is likely a windage tray.

 

[doberman-guy]

Re: 1980 OMC 230hp 350 question.

The outdrive is on the boat. It was replaced with a newer one before i got the boat. This was all a trade deal and i wasnt aware to the extent of any problems. How woud i test to see if the drive may be froze? I can turn the propeller in neutral if that means anything. I'm not 100% sure the engine is siezed yet, i just cant turn it with the starter or any other method at this moment. thanks again for your responces.

 

[Boomyal]

Re: 1980 OMC 230hp 350 question.

There is no disconnect between the engine and the outdrive. If the upper gearcase is siezed it will keep the motor from turning over. Your gear selector may still disconnect the prop and let it spin freely.

The only way to know for sure is to pull the whole outdrive, hence disconnect the two ball gears from each other.

When is the last time you ran the motor? How does the oil look? How do the spark plugs look? Any signs of rust on them? Any chance the engine was not winterized?

 

[doberman-guy]

Re: 1980 OMC 230hp 350 question.

The plugs look fine no rust, the oil did not look good. looked like it wasnt changed in along time, it was real thin and greyish orange in color. I never ran the boat, just got it a couple of weeks ago. I was told it ran when it was put away, that was a few years ago and i cant say it was winterized or not, but there is a can of fogger and gas stable in the boat but i cant assume anything. Also the boat sat under the sun awhile as im redoing the teak wood and removed 9 wasps nest.

I guess i will have to look at the outdrive now before i tear into the block. If anything, I hope its the engine there much easier to find and cheaper?

 

[Gettinther]

Re: 1980 OMC 230hp 350 question.

My suggestion would be : #1 remove the drive, #2 try to turn input shaft of drive by hand, if it will turn proceed to engine

remove all sparkplugs inspect for rust and debri ,oil and or water in cylinders, if looks bad lubricate with seafoam in excessive amounts,
if looks good lubricate with seafoam in excessive amounts continue to try cranking by hand method. If that fails remove rocker cover and inspect for seized valves ( tap gently with hammer) if they are siezed the engine will not turn if seized remove manifolds and lubricate with seafoam in excessive amounts thru exhaust ports, go have 2 coffee and return to try hand cranking again. If you get this engine to turn by hand connect battery and spin engine with starter in short cranks until it sounds smooth and free.
At this point (after 2 coffee)you will have a good idea if its going to be replace the engine or continue with the old, this was more or less the method I used on the engine in my post, my engine sat for 10 years, full of rust in 2 cylinders, siezed valves in one cylinder, now runs well, but I need to replace the raw water pump in the electric shift outdrive

Good luck

 

[doberman-guy]

Re: 1980 OMC 230hp 350 question.

Thank you very much for your input. I will be sure to try the exact method you described. I will keep you posted

 

[doberman-guy]

Re: 1980 OMC 230hp 350 question.

Had outdrive off and everything is good. Now on to the engine, i better get some coffee ready.

 

[Gettinther]

Re: 1980 OMC 230hp 350 question.

Had outdrive off and everything is good. Now on to the engine, i better get some coffee ready.

Good luck

 

[doberman-guy]

Re: 1980 OMC 230hp 350 question.

Well the heads are off, and Seems two pistons are rusted tight. I used a whole can of pb blaster so far and they still wont budge. I've pounded on them a little with a 2x4 and a hammer, not sure how hard to hit them or what the purpose of hitting them really does. Anybody know if tranny fluid will do a better job at breaking these free, or how about seafoam? Its been about 12 hours since i tried to move them, I hope I can start to get them to move a little bit today.

 

[Gettinther]

Re: 1980 OMC 230hp 350 question.

Well sir, in my opinion and past experience if ya can't get em to move with a hammer and block of wood its time to pull it and rebuild or replace.
I wish ya lots of luck, if ya keep tryin but usually if they are froze that bad the rings will snap,and or piston will crack when it does move.

Thats just my experience tho.

 

[RogersJetboat454]

Re: 1980 OMC 230hp 350 question.

Well the heads are off, and Seems two pistons are rusted tight. I used a whole can of pb blaster so far and they still wont budge. I've pounded on them a little with a 2x4 and a hammer, not sure how hard to hit them or what the purpose of hitting them really does. Anybody know if tranny fluid will do a better job at breaking these free, or how about seafoam? Its been about 12 hours since i tried to move them, I hope I can start to get them to move a little bit today.

Stick a fork in her, shes done. Don't waste any more time on this. Even if you some-how get this freed up, this engine would be an oil guzzling slug.

If you want the cheap way out, find a pre '86 truck engine with good compression and oil pressure (if it's possible to run it). Install brass core plugs in it, along with a marine grade head gaskets (these are a must if running in salt water). You should also consider installing a marine grind cam, although a STOCK truck cam is fairly close. If this is a salt water boat, install new exhaust manifolds/risers. If this is a fresh water boat, thoroughly check your exhaust manifolds/risers for excessive scale, and leaks. Check your cooling passages in your intake. Swap everything else over as necessary. Install an impeller kit in the drive.

Or you could get a complete reman long block here for 1,400;
http://www.rapidomarine.com/default.aspx?p=/engines/default.aspx

 

[doberman-guy]

Re: 1980 OMC 230hp 350 question.

She is free and with not much effort. I am a happy man!! Thanks to all for your help. RogersJetboat454, thanks for the advice i will keep that in mind should something else come up.