Did I do this right?

[bsh21wash]

I was winterizing my boat (OMC 4.3 V6) yesterday and in the manual it says to pull the two hoses off the manifolds, I did this but not water came out. The hose are level with the manifolds so I dont see how water would drain out. Shouldnt there be some kind of pet **** on the manifold? I drained the two on the block. It just doesnt seem right, but thats all it says to do in the service manual.

 

[HT32BSX115]

Re: Did I do this right?

My 87 OMC service manual mentions something about using anti-freeze to winterize by pouring it into the engine.

The following is excerpted from my manual 1987 Cobra service manual #507605


"Optional Winterization Procedure:

1. Close all petcocks and replace rubber caps and clamps if equipped.

2. Remove upper end of large water pump hose at thermostat assy.


3. Pour 50/50 water antifreeze mizture into the hose until antifreeze appears at the thermostat opening


4. Reinstall hose on thermostat assy.

5. 2.3L models: Remove transom bracket water hose at thermostat housing. slowly pour AF into hose until manifold and hose is filled . Reconnect hoses.

6. Remove long hose from the gimble housing to the thermostat housing at the thermostat housing. pour AF into hose. depending on waterpump impeller position the AF may not fill the hose. Pour only enough AF to fill the hose or until 1 qt has been used."



Filling the engine and associated heat exchangers (oil, power steering etc) is not a bad idea.




In any case, ensure that when you initially drained the engine remove the valves from the block and poke a wire or small screwdriver into the hole to clear out the rust and sand that usually plugs the holes or you will not get all the water out. It doesn't take much to crack a block. Soft plugs will not help you. they're not there for freeze protection.




Cheers,

 

[Haut Medoc]

Re: Did I do this right?

I'm not an OMC guy, but I would think it should have some drains.....
It's getting pretty chilly in the 'burbs at night now......
Hopefully someone more informed on your set up will chime in....​

 

[skeat]

Re: Did I do this right?

I pull off the water pump hose at the water pump rather than at the thermostat housing and water will drain out of that. The other house that runs to the back of the engine I disconnect in the front but then hold it down low to drain it. There are 2 drains on the block but also on each of the exhaust manifolds. The drive has 3 screws to remove to drain that. Even when I was in Maine I've never put antifreeze in and that was with days on end never getting above 20 degrees F, never had a problem. antifreeze certainly wouldn't hurt though.

 

[Boatin Bob]

Re: Did I do this right?

To drain those manifolds you need to remove the rubber caps on the back end of each manifold.

 

[bsh21wash]

Re: Did I do this right?

There is two brass fittings on the back of the manifolds but there still level to the manifold, so I dont see how this would drain everything.

Yesterday I pulled the hose connected to the thermostat housing and the hose connected to the water pump, lots of water came out. Also the two petcocks on the block which also had lots of water that came out.

Now when I pulled the hose's off the manifolds that have brass fittings that face up and I can see water in them. I dont understand why there isnt petcock on the bottom of the manifolds to drain water??

Thanks

 

[Arima90]

Re: Did I do this right?

On my 1988 OMC Cobra 5.0L, there was a rubber cup and hose clamp underneath both manifolds. If you reach underneath the manifold and run your hand toward the rear (stern) there should be one.

 

[a70eliminator]

Re: Did I do this right?

this is straight from the OMC Cobra service manual for 1990

4.3L & 4.3L HO
1- disconnect and drain long hose at T-stat housing
2- disconnect and drainlarge hose at water pump housing
Starboard
1- open one exhaust manifold petcock
2- open one cylinder block petcock
Port
1- open one exhaust manifold petcock
2- open one cylinder block petcock


There are some photos of the manifold petcock and it's dead on the bottom of the manifold.

 

[whywhyzed]

Re: Did I do this right?

If there's a few tablespoons of water in the manifold it ain't gonna matter - Ice breaks castings when it expands and pushes the sides out. A little puddle of ice sitting in there isn't going to wreck the boat.

That said- this pic clearly shows a drain plug or fitting for petcock on the bottom - not sure why yours wouldn't have it

 

[Dakota47]

Re: Did I do this right?

Thats how mine are. 1987 OMC 4.3 . 1 drain under each manifold and 1 drain on each side of the block. total of 4 drains. very easy to do.

 

[Bayliner1992]

Re: Did I do this right?

Why is he doing all that if he is going to winterize it? you are going to empty water to put anti freeze, logically the anti freeze would push out the water correct! i know your not going to leave it empty so it can rust right, so what's the fuss? lol

 

[Boatin Bob]

Re: Did I do this right?

The pic below is for a 1991 4.3 and it shows item 10 as being the rubber cap to come off the end to drain the manifold. If your manifolds look like the pic that kjdkjd posted then maybe you've really got a 1990 engine? What's the model #?