Changing water separator


I suppose this topic should be under another heading. Yes, if the chokes are working, they should come off by themselves. Mine were old, mechanical chokes and I got tired of adjusting the choke stats. Removing them proved much easier and the engines burned leaner and cleaner when cold. I never saw fuel floating around after start up, which was the other main reason I removed them.
I solved two problems by doing so and I never looked back.
When I sold the boats, I advised the buyers, and asked if they wanted the chokes reassembled. Both buyers said no as they did the same thing. I guess to each, his own. EFI killed this long lived debate of the good 'ol days.
 
Any tips on removing the filter? I’ve tried the filter socket, but the wrench’s square tooth sticks in too far so it makes the socket only half way grab (and slip off). I’ve tried a filter wrench with metal teeth but it slips (filter is on too tight).

Also, I replaced my mechanical fuel pump, while it was off and I looked down the hole it goes in, I noticed it wasn’t clean where the lobe is (block side of the mount) and it was really gritty looking. I’m guessing this is why the spring failed on the pump. Is there a way that area is supposed to be cleaned?
 
Buruskeee said:
Any tips on removing the filter? I’ve tried the filter socket, but the wrench’s square tooth sticks in too far so it makes the socket only half way grab (and slip off). I’ve tried a filter wrench with metal teeth but it slips (filter is on too tight).

Also, I replaced my mechanical fuel pump, while it was off and I looked down the hole it goes in, I noticed it wasn’t clean where the lobe is (block side of the mount) and it was really gritty looking. I’m guessing this is why the spring failed on the pump. Is there a way that area is supposed to be cleaned?
Click to expand...


Firstly, and don't take this the wrong way but ensure you're turning it the correct direction. It's mounted upside, most likely.
Next, I have had luck with wrapping the filter with a non skid material like a rubber strap. Many years ago, while changing a buddy's oil filter, I stole my wife's rubber jar-opening cloth. A rubber glove will work as well.
Also, try a little nudge in the tightening direction first. Sometimes you just need to break that grip.
Don't forget to check the housing face once it's off. Make sure you got all of the old gasket off. Good luck.
 
The mechanical pumps are diaphragm pumps so they will not “burn out” if they run dry for a bit. Most external electrical pumps are too but the motors will begin to heat up when there isn’t fuel flowing through them to create resistance and act as a heat sink as well.

It is not necessary to pre fill the separator/filter as the pump will move a sufficient quantity of fuel to refill it almost instantly. The same goes for the oil filter. You are just increasing the chances of spilling and making a mess by doing this.

What you do want to do is just like your oil filter is use a little bit of the motor oil on the tip of your finger to lubricate the gasket before tightening it on so that you will be able to take it off more easier later. @Buruskeee I suspect this is your issue. The gasket has sort of bonded to the metal thanks to engine heat and you just need to get it to break the extra strong seal the dry rubber has formed with the metal surface is all.
 
Buruskeee said:
Any tips on removing the filter? I’ve tried the filter socket, but the wrench’s square tooth sticks in too far so it makes the socket only half way grab (and slip off). I’ve tried a filter wrench with metal teeth but it slips (filter is on too tight).

Also, I replaced my mechanical fuel pump, while it was off and I looked down the hole it goes in, I noticed it wasn’t clean where the lobe is (block side of the mount) and it was really gritty looking. I’m guessing this is why the spring failed on the pump. Is there a way that area is supposed to be cleaned?
Click to expand...

On the filter removal, a strap wrench with a wide rubber strap can work wonders, it you have room. Filters that tight usually indicate last installer didn't oil new rubber ring with clean oil, or tightened way too tight. Spin on new filter till o-ring touches then another 3/4 turn. That's all that's needed.

That cavity in the housing under the fuel pump should be serviced every year. There are 2 screw type plugs in the side. If pump is off, just pull bottom plug and drain out. If there is water in the oil, the housing bearings and seals need to be refreshed. Put the plug back in and fill housing to the bottom of the top plug with Mercruiser High Performance outdrive oil. That's it. Also, it it smells like fuel, that could indicate the fuel pump is leaking fuel into the housing and is about to completely go bad.

If it is super nasty in there, maybe time to remove and rebuild. They don't get nasty for no reason. Not difficult to completely rebuild one. Bearings and seals readily available.

If just doing the oil change, pull top plug. Pull bottom plug and drain. Used drive oil pump to fill through bottom hole till oil seeps out of top hole. Put top plug in. Remove the fill pump fitting (will dribble oil out). Install bottom plug.
(I use an oil pump can into top hole till it dribbles out top hole and put in plug)
 
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These little guys are invaluable at times.

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