New to Forum

[Danny in CO]

Hi, I'm new to the forum. I just bought a used 19' boat last weekend. It has an OMC 5.0L Cobra engine/outdrive in it. I took it out last Saturday. It ran a little rough and wouldn't take full throttle without bogging down. Also, the temp never came up. I have ordered the shop manual for this setup but it won't be here until later this week or early next week. So being impatient. I have a few questions.

Yesterday, I changed the plugs which helped it run much smoother and will rev without bogging down. Of course this was in neutral and with the water muff on it. I will time it today if it doesn't rain. Hopefully this will solve the bogging problem.

On the starboard side on the block there is a petcock drain. On the port side is what looks like a temp sender without any "guts" in it and no wires. Is this supposed to be the temp sender or is the sender somewhere else?

On the back there is a 3" or 4" rubber hose coming from the engine to the outdrive that water leaks out of when running with the muff. I assume there should not be leaks here. I assume it should exhaust the water out through the prop. Is this a problem since the water still exhausts or does it need to go through the prop to cool something?

Thanks in advance for your help!
Danny

 

[Boatin Bob]

Re: New to Forum

Should have the petcock drain on both sides of the block.
Temp sender should be mounted in the intake manifold near the the t-stat housing.
Your probably seeing water come out the exhaust bellows, a lot of the newer ones actually have slots in the bottom so don't worry about that.



ps...welcome to the forum!!! (where are my manners?)

 

[Gary H NC]

Re: New to Forum

Welcome Danny,
You may also want to look for a fuel water separator filter...looks like an oil filter.Change that if it has one.
Look over the cap,wires and set the points and timing..
Good luck with your new boat!
Use only the AC MR43T spark plugs..

 

[Danny in CO]

Re: New to Forum

Welcome Danny,
You may also want to look for a fuel water separator filter...looks like an oil filter.Change that if it has one.
Look over the cap,wires and set the points and timing..
Good luck with your new boat!
Use only the AC MR43T spark plugs..

Thanks for the replies, guys!

Gary, there is a filter on the starboard front of the engine and what I think is the oil filter on the port rear. Is the one on the front the fuel water separator? Does this just filter out the condensation from the fuel? I used NGK RU4 plugs. Are the AC MR43T better (hotter or colder)?

Thanks, Danny

 

[Gary H NC]

Re: New to Forum

The filter in the front should be the fuel filter.Take it off and pour the fuel in a glass jar.That way you will see if water was in it.Replace the filter anyway.
Napa auto parts sells them from their marine book.Or West marine or Bass Pro shops ect..
The AC plugs are what the factory calls for.Some OMC motors just did not like running other brands of plugs.
I buy my plugs from Rockauto.com...about half the price as most other places.
Once you get the service manual i would then change the water pump impeller in the outdrive.Very easy on a Cobra..
I hope you found an Original OMC manual. The after market Seloc and Clymers are not that specific.

 

[Danny in CO]

Re: New to Forum

The filter in the front should be the fuel filter.Take it off and pour the fuel in a glass jar.That way you will see if water was in it.Replace the filter anyway.
Napa auto parts sells them from their marine book.Or West marine or Bass Pro shops ect..
The AC plugs are what the factory calls for.Some OMC motors just did not like running other brands of plugs.
I buy my plugs from Rockauto.com...about half the price as most other places.
Once you get the service manual i would then change the water pump impeller in the outdrive.Very easy on a Cobra..
I hope you found an Original OMC manual. The after market Seloc and Clymers are not that specific.

DARN! The one I bought is the "Clymer OMC Cobra Stern Drive Shop Manual 1986-1993". I guess I'll look for the original OMC manual. Which manual do I need? The Operator/Owner's Manual, The Service Manual, or the Shop Manual?

Thanks!

 

[Boatin Bob]

Re: New to Forum

The NKG UR4's will be fine, you want the service manual something like this one, what year is your engine/drive?

http://cgi.ebay.ca/1989-REAL-COBRA-...26453QQcmdZViewItemQQ_trksidZp1742.m153.l1262

 

[Gary H NC]

Re: New to Forum

Bob is correct about the manual.That seller on Ebay is a friend of mine.If you have problems finding the correct book let me know and i will give him a call.
You want the OMC service manual for your year of engine and drive.They have 100 times more info and great pictures for any repairs,colored wiring diagrams and very specific shift adjustments that are critical on a Cobra drive.

 

[Danny in CO]

Re: New to Forum

Mine is a 1986 model. I sent the e-bay seller an e-mail to see if he has the service manual for mine.

Thanks, guys!

 

[Gary H NC]

Re: New to Forum

He may have one thats not listed in his Ebay Store.
Tell him Gary in NC sent you..
Here is a 1987 that was actually printed in 1986,it would be just fine.
http://cgi.ebay.ca/1987-OMC-COBRA-S...26453QQcmdZViewItemQQ_trksidZp1713.m153.l1262

 

[Danny in CO]

Re: New to Forum

He may have one thats not listed in his Ebay Store.
Tell him Gary in NC sent you..
Here is a 1987 that was actually printed in 1986,it would be just fine.
http://cgi.ebay.ca/1987-OMC-COBRA-S...26453QQcmdZViewItemQQ_trksidZp1713.m153.l1262

I e-mailed Don and he is out of the 1986 but said he has a 1989. He said it is very similar. What are your opinions? Should I get the 1989 or keep looking for an 86?

Thanks

 

[Gary H NC]

Re: New to Forum

This link here is the 87...its a little more expensive but i would choose it over the 89..There really is not much difference,Those drives changed very little if any between 86 and 89.
http://cgi.ebay.ca/1987-OMC-COBRA-S...26453QQcmdZViewItemQQ_trksidZp1713.m153.l1262