Mercruiser 4.3 LX alpha one

[Waitkei]

Raw water feed. I can not get any raw water in. I Have changed impeller flush out a the system, changed thermostat. I have checked impeller is correct way 5 times but still no raw cooling water getting delivered. Things I have tried... Putting hose pipe on copper tube in leg but no water will go up. I have tried flushing backwards through the raw water pipe that attaches to the power steering cooling manifold. Any help greatly appreciated.

 

[Waitkei]

I have taken every water pipe off, drained and flushed through the two brass bottom drain plugs until the cows have come home. The only thing I can now think off is that there is blockage in stern drive after where the copper pipe from the impeller housing goes through the stern. Everywhere from there appears clear .

 

[Waitkei]

So my thoughts are... If the raw water pump is good with new impeller which is correctly installed. There is a blockage after copper pipe in that plastic housing going through the stern. If this is the case how do you take the plastic housing apart and what is it called? I do see four bolts looking up the alpha one leg. Thanks Waitkei

 

[alldodge]

Was it working ok prior to replacing impeller?
Was the key reinstalled to (item 29)

https://www.mercruiserparts.com/bam/subassembly/30858/1017/80

When doing a reverse flush is any water coming out anywhere on the drive?

 

[Waitkei]

hello alldodge. reverse flush was carried out from hose that leaves the stern, the raw water feed. i disconnected the water hose at the feed side to the power steering manifold with lower out-drive leg off, I put hose pipe in the hose and it just blew back. Then i tried forward flush by attaching hose on copper pipe in alpha one leg and same again it just blew back. so my guess is blockage in that plastic coupling what ever it is called that connect the copper pipe to the feed hose for the raw water after the stern drive.

 

[Waitkei]

yes the key was installed correctly to the lock the impeller, no it was not pumping water properly prior to installing the impeller, gain i think it might be bad hose... the first flexible hose as the water leaves the stern drive or that plastic housing. I have checked and cleaned and reversed flushed everything else and it all appears ok. Thanks waikei

 

[alldodge]

I would remove and split the drive, then flush to determine what is blocking it

 

[Rick Stephens]

Takes 10 minutes to pull the upper drive off and make for simpler testing.

 

[Waitkei]

so it should just flush straight through from the copper pipe to the end of the first flexible hose. there are no non return valves? also do you know the name of that plastic manifold going through the transome? thanks waitkei

 

[Waitkei]

i notice that the first raw water hose port side at stern is at a funny angle as it attaches to the stern transom connection as one side edge appears flush to the connector but the side is some 1 inch away from the edge of the connection. there are two bolts holding this connection to the stern,is there a diagram of this connection out there? also is there a part number for this preformed hose, its the first raw water hose inside the boat that attaches the transom to the power steering cooler manifold before the raw water then going to the thermostat manifold. Thanks waitkei.

 

[alldodge]

You happen to have a thru hull fitting?
Post a pic of what you have

 

[Waitkei]

41642A3 its that hose there transom to oil cooler. its blocked and a funny shape right on the transom and will not pull of from the connection there. I loosened the the hose clip but it will not pull loose :-( is there a diagram of the connector out here?

 

[Waitkei]

on the diagram of the new hose 41642A3 there are two circular or round rubber blocks, any idea what are they for?
Thanks Waitkei

 

[alldodge]

I have not seen a serial number or year of your motor and don't know which drawing your looking at

 

[Waitkei]

[h=1]Mercruiser Hose Transom to oil cooler 32-41642A3. It's alpha one 4.3 LX 1992. Should the raw water flow freely under hose pressure with no interference when the hose is disconnected at the oil cooler and the copper pipe disconnected at the raw water leg pump? Or are there mechanism in the plastic connection after the copper pipe in the leg going to the transom or the plastic conection at the stern in the boat transom where the oil cooler pipe attaches, I have tried to flush both ways and water died not go through. Thanks Waitkei[/h]

 

[alldodge]

The power steering cooler is a straight thru tube with no restriction. I have seen one which some how was closed up by the inner tube being expanded somehow.

Remove the cooler and you should see just a tube

 

[Waitkei]

Mercruiser Alpha One, Transom Gimbal housing 5/8" Pick Up Water Hose Alpha 1. Do you need to take leg off the change or inspect this hose?

 

[alldodge]

Appears were not talking about the same thing.
I'm talking about inspecting the PS cooler (item 23) and your in the drive

https://www.mercruiserparts.com/bam/subassembly/31517/1619/120

 

[Rick Stephens]

Mercruiser Alpha One, Transom Gimbal housing 5/8" Pick Up Water Hose Alpha 1. Do you need to take leg off the change or inspect this hose?

This is ridiculous. PULL THE DRIVE OFF!

This is one of the easiest tasks, an annual one at that. Separate your problems. Pull the drive off. Pull the hose off the oil cooler. Blow air through hose from cooler. You are making this impossible to help you.

 

[Waitkei]

Do you need to remove the alpha one outdrive to fit a new gimbal water pick up hose?