OMC I/O problems

Joined
Sep 2, 2009
Messages
15
I've purchased a nice used 1988 four winns crusier this summer. It has a 4.3L
V6 with a Cobra OMC I/O. After having the I/O repared 3 times this year
for varous cooling problems, now it is locked up and the engine won't
even turn over. I've given up on the marina. I seem to always get the
same story and a large bill. What should I do? I love the boat, just not
the I/O$$$$$.:confused:
 
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TowRoper

Petty Officer 1st Class
Joined
Jul 24, 2009
Messages
302
Re: OMC I/O problems

we need some back ground on what it was doing b4 it locked up, things like noise clunks bangs leaks you name it we need it in order to help and don't give up it will work out in the end!
 

dr_bowtie

Petty Officer 1st Class
Joined
Aug 4, 2009
Messages
281
Re: OMC I/O problems

welcome to the forums...

you're not in the Lake Wawasee area in Indiana are you...?

pull the spark plugs and see if you can roll it over easily with a breaker bar...listen for any sounds and/or water coming out of any cylinders...note that and post it as well...
 
Joined
Sep 2, 2009
Messages
15
Re: OMC I/O problems

My 1988 four winns had set unused for 2 years. It had been winterized and the fuel in the tank treated with 'stable'. I took it to a marinia after buying it to have a cooling problem repared and to have a tuneup. Since then it has been in 3 times totaling into the thousands. The last time I was told it was repaired, however they left the thermistat out to 'let any more foregn objects to flow freely out of the system. The tank at this time was full of new 89 oct. gas and I had a eng. timer installed. After 4 eng. hours my wife and I were out in a daytime cruise around the lake and the motor just stopped. No noise. Just silence. It is now in my front yard as I refused to have them take another $600 'look at it'. The moter turns over. It will not start. No mater where the shaft control is it is stuck in forward as the prop moves when you try to start it. HELP!!:eek:
 

a70eliminator

Captain
Joined
Sep 9, 2007
Messages
3,762
Re: OMC I/O problems

Can you spin the prop by hand, if so then don't worry about the prop spinning while starting thats normal, the spinning gear set will sling oil withing the drive and cause the prop to free wheel a little. Spark + fuel = fire, but it has to happen at the correct time (timing).
 

proshadetree

Lieutenant Commander
Joined
Jul 19, 2008
Messages
1,887
Re: OMC I/O problems

Like stated with the shifter in neutral hand spin prop.Get a spark plug and plug into a plugwire ground on engine.Have someone turn engine over.If *** sparks get starting fluid and tap a small amount into intake.If it dont do something post back.
 
Joined
Sep 2, 2009
Messages
15
Re: OMC I/O problems

I've tryed your replies and I thank you for them. Something is 'stuck' as the motor will not turn over fast enough to fire. It seems it is acually 'stuck' in forward' and I'm not sure how to release it. I have a clymer (I think that's the printer of it as it is in the boat and I'm in here typing this) mantenance manual. I've been through it many times and I hounsetly don't know what to do other than pull the I/o off and try to fire the motor with out it.:( As for the reply am I at Wawasee Indiana, yes I am. I grew up here and moved back after several years in the army. It seems smaller now then when I was young. Compared to the great lakes or Ocean excursans it almost is a deep long pond. But the fishing is great:D
 
Joined
Sep 2, 2009
Messages
15
Re: OMC I/O problems

Great news!:DThe motor now runs. I said a few prayers played with the shifter pumped the throttle twice while the shifter was in neutral position and after a few tryes the motor 'spinned' faster, it fired and then it ran. I did not let it run too long as I did not have 'muffs' on it. But it sounded fine. The I/O made some funny noises like it was dry(as in no lube). I checked the lube level and it was full. What should I do next to make it sea worthy?:confused:
 
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proxyx

Banned
Joined
Aug 28, 2009
Messages
135
Re: OMC I/O problems

check if shift cable ok (alignment) and shifting freely... I once had prop locked, couldn't start until it was freed, maybe this happened to you, if so shifting may be an issue, worth checking, look into service/troubleshooting manual (adult section on top of the forum)
 

sea wolf

Lieutenant Junior Grade
Joined
Apr 3, 2002
Messages
1,219
Re: OMC I/O problems

Great news!:DThe motor now runs. I said a few prayers played with the shifter pumped the throttle twice while the shifter was in neutral position and after a few tryes the motor 'spinned' faster, it fired and then it ran. I did not let it run too long as I did not have 'muffs' on it. But it sounded fine. The I/O made some funny noises like it was dry(as in no lube). I checked the lube level and it was full. What should I do next to make it sea worthy?:confused:
Change the impeller. You probably fried it when you ran it off the muffs. It only takes a few seconds. You need to grease the gimbal bearing & u-joints also, & the drive has to come off to get to the u-joints. Did u put the t-stat back in? If not, do it. The mechanic that left it out ain't too bright.
 
Joined
Sep 2, 2009
Messages
15
Re: OMC I/O problems

The impeller is fine. Not sure about the Gimal/universal joints are greased. I'll get some rather large chaps over and pull the unit out and see..What was the other thing you mentioned...T-stat:confused:Never heared of that. I am not a professional mechnic. But I have always, in the end had to work on my own motors. My experance is limited to outboards. I have always had I/O's done by marinias. This is my first OMC. I had Mercurser I/Os before. I will also check the shifter. Thanks for everyones input.:
 
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dr_bowtie

Petty Officer 1st Class
Joined
Aug 4, 2009
Messages
281
Re: OMC I/O problems

thermostat is in the engine/water system
 

King P.V.

Seaman
Joined
Aug 13, 2005
Messages
72
Re: OMC I/O problems

Befoere you do anything else, I'd suggesr you remove the top cover on the outdrive. Now you can look down and see the oil thwt should be there. If you just removed a drain plug, you may find oil but it's the correct leval of oil you're looking 4. If it's not covering the input gears 1/2 way, then you've lost oil, it was miss-filled and now the aft bearing is toast>> Who fill'd up the outdrive last?? And how did they do it?? I always tell people to not just drain the oil, but to check for the proper level first!!
 

danond

Lieutenant Junior Grade
Joined
Jun 11, 2007
Messages
1,118
Re: OMC I/O problems

Boats that rely on raw water for cooling should never, ever be started without a water supply. EVER. Not for 1 second.

But, because you did, you have now toasted your raw water pump, sometimes called an impeller. It will need to be replaced. There's no way you know if the impeller is any good unless you've replaced it and it explains why you are in the shop for cooling problems on a continuous basis.

You have a long service and maintenance list ahead of you. I/O drives are fiddly and require much attention to be reliable.

Also get a real service manual - the one produced by OMC.
 
Joined
Sep 2, 2009
Messages
15
Re: OMC I/O problems

Thanks I will. That Clymer does not have enough detail in it. I went to my dad's and borrowed Muffs. The moter ran for a while. Then I winterized it. Unfortunetly the greese in the Upper unit had water in it,(It was white). The Lowe unit assembley HAD ZERO GREESE!!! I Do intend to keep it as my father and I have been doing interors in Boats for many years. Such a shame. The Boat is in great shape. The V-6 GM motor is newly tuned and winterized. But I fear the I/O is DOA:mad:
Any Suggestions on who could refurbish the I/O correctly within a 100 mile radias?
 
Joined
Sep 2, 2009
Messages
15
Re: OMC I/O problems

I'm sorry, but I'm afraid I don't understand. Accourding to the maint. manuel and several mech. I've taked to their is an upper section and a lower section. Are you saying that both, as far as the lubrication goes, are conneced? Their is an upper and a lower lubercation screw and a upper and lower lubrication drain. I'm really confused now:confused:
 

bruceb58

Supreme Mariner
Joined
Mar 5, 2006
Messages
30,592
Re: OMC I/O problems

3 screws...lower drain, middle vent(fill point) and screw on top that has dipstick. Upper an lower unit share the same oil cavity.

You know that you fill from the middle hole right? Any other way and you will kill your drive.
 

dr_bowtie

Petty Officer 1st Class
Joined
Aug 4, 2009
Messages
281
Re: OMC I/O problems

have you tried the marina on US 6 and 9?

they dont have alot there but they are pretty close to you...

there are several marinas near me but they are all expensive...they charge 95.00 per hour and up to 150.00 per hour on odd-ball stuff...

you still doing boat interiors...? I am looking to get a few things recovered myself...
 
Joined
Sep 2, 2009
Messages
15
Re: OMC I/O problems

Never Been there. But yes that is within 40 miles. I've found a nice replacement I/O. It will prob. take me all winter to save for it. But I think it'll be worth the wait as it's brand new and carries a 3 yr warranty. I'll check out the marinia you suggested. It would be nice if they could install it for me. I'm draining the block right now as it get's pretty could up here in about 2 months. I've found the 4 T drain plugs and the proper rubber hoses to disconnect, but I can't find the back 2 Tdrain plugs on my OMC 4.3 L V-6 any suggestions on a location tip? The Clymer book just does not show very good desc. prictures.:confused:
 
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