First I/O, what to do?

[pulleyman123]

Hi all!
1987 OMC Cobra 4.3L I/O

I was just given this boat from a friend. The boat sat last season. The girl is not sure if it was winterized but believes that it was. How could I tell if it was winterized? So to get right into it, I ordered the manual so please don't yell at me for that. What would you guys recommend doing to this motor before trying to fire it up for the first time? I'm thinking: plugs, wires, rotor, cap, fuel filter, oil filter, impeller, motor oil, gear oil. Is all of that necessary and what additionally would you recommend. I really don't want to screw this engine up. The girl that gave it to me said it ran great when she used it but just didn't have time for it, poor baby (the boat I mean). Thanks for any help.

 

[arks]

Re: First I/O, what to do?

Boy, where do we start....
First, I'd pull all the spark plugs and check their condition. If you detect any rust in the combustion chambers, that's bad news. Assuming it looks OK, squirt a little light oil in each hole and replace the plugs.

Try to find out how old the gas is, and if it was stabilized. Old gas is bad.

Next, charge up the battery and install muffs so it can be tested on the trailer. Start the water flow and see if she'll crank.

If she cranks, go ahead and start 'er up. Make SURE you have good water flow thru the outdrive or you'll cook the impeller, then the motor. If you see a lot of water coming out of the engine itself then it probably wasn't winterized properly and you've got some problems.

I'll let some of these other guys take it from there!



.

 

[pulleyman123]

Re: First I/O, what to do?

How will I know if the water is circulating good enough? and where would I see water "coming out of the engine"?
Thanks for the help!

 

[arks]

Re: First I/O, what to do?

How will I know if the water is circulating good enough?

It'll circulate just fine as long as you have normal house pressure against the muffs and they're put on the outdrive correctly.

Where would I see water "coming out of the engine"?

Hopefully you won't! If a freeze plug is busted or the block is cracked it'll be coming out of the side, usually below the heads.

 

[Fishermark]

Re: First I/O, what to do?

By "water coming out of the engine" I think "arks" is saying that would indicate the block is cracked - not a good thing.

EDIT -- Looks like we were posting at the same time!

 

[Dakota47]

Re: First I/O, what to do?

Make sure the drain plugs are tight on engine.

 

[Lou C]

Re: First I/O, what to do?

First thing, you know that OMC is out of business, right? and OE parts are not 100% available, but much is in the aftermarkt. You basically have a couple of choices, one, try to find a marine mechanic who knows OMC Cobras and let them check through it for you, to get it in shape for the season. The other, is if you want to do some of the maintenance yourself, get an Original OMC Manual, you can find them on E-bay, they are much better than the aftermarket ones. As far as the Cobra goes, the main differences from Merc are that
1 you fill the drive from the second screw up from the bottom on the drive, not the bottom screw on the 'bullet' , the proper screw is just below the joint between the upper and lower gear cases (do a search for the complete filling procedure, it must be done right, or you will ruin the upper gear set!)

2 the impeller is actually easy to replace, right behind the plastic cover held on by 3 screws on the rear of the upper unit

3 the transom shift cable adjustment is tricky and should not be attempted by an amateur to OMCs, if it does not stay in gear, or won't shift to neutral, take it right to the best OMC shop you can find and let them fix it.

 

[watermellonI]

Re: First I/O, what to do?

ok you wanna run it:

1 check plugs, fuel and oil, charge battery

2 outdrive all the way down, never run while in up position

3 attatch muffs, put water to muffs, make sure water is coming out of bottom portion of stern drive. s/b no water in engine comp. if there is water in engine comp make sure its not comming from the engine, hose or freeze plug, if it is stop here

4 check oil again, if your oil level has changed, stop here

5 crank, listen to motor and starter, s/b no clunkin or clankin if motor starts watch temp as she warms up don t let her get hot, warm is app 120 deg.

if you make it this far with no problems your probably ok and may just need a tune up

This is just the beginning.

Good Luck!!!

 

[Dakota47]

Re: First I/O, what to do?

keep us posted..

 

[pulleyman123]

Re: First I/O, what to do?

will definately keep you posted.

I'm starting with the basics today.

Now, theres no such thing as a stupid question, only stupid answers, right?

well, if I get this thing going on land (with muffs), will I have to winterize it again if the temp here has been dropping to around 20 degrees at night (long island) and still a bit more winter to get through?
thanks for all your help.

 

[Uraijit]

Re: First I/O, what to do?

Yes, you will need to "winterize" it every time you put water in it during the freezing season. Probably best to just wait 'till it warms up before you go putting water back in it. If you go through with putting water in it now, you won't need to do a complete winterizing, just get ALL of the water out of the engine and drive.

 

[Lou C]

Re: First I/O, what to do?

I agree on waiting some, you still have all of March to go through and we can still have freezing weather then and trust me it is no fun to be fiddling with drain plugs on a 21 year old motor when it's 30* out, you will freeze off your fingers if one gives you grief. And BTW, those one piece exhaust manifolds, are just about impossible to find, so you don't want to crack em.

When the time comes...unless you take it to a good OMC mechanic (safest course if you are a beginner) before starting, make sure that:
1 the muffs fit tightly
2 you have a good hose that won't kink, I use 3/4 in heater hose
3 check the engine oil level, it may be off a bit depending on the level that the boat is tilted at during storage
4 check the drive oil level, there is a cover on the top of the upper unit, it's held on by 4 bolts, in the middle is a large screw, that is a dipstick that's where you check the oil. Remember, any time the engine is running, the upper gears spin, even in neutral, so if you start it and the drive is low on oil, you can ruin the upper gears.
5 Make sure there are NO GAS FUMES in the bilge before starting, run the bilge blower
6 When you run it make sure no one in the house does the wash, or takes a shower, that can drop the water pressure enough to overheat the motor (don't laugh happened to me!)
7 Once it starts, make sure water is exiting from under the transom mount, that is where it normally exits on a Cobra at idle, if not, shut it off right away. You will need to trouble shoot the water flow issue first.
8 When running it keep an eye on the temp gauge (should stablize at 160*) and oil pressure gauge (mine will idle -cold engine- at about 40 psi, then lower some at hot idle).
9 Unless you remove the prop, keep people and animals away from the prop, if you knock it into gear by mistake a tragedy can occur
10 While it's running check for water leaks all around the engine and exhaust system
do a search for the Stuart Hastings Cobra site, that will tell you all you need to know about Cobras.