Flushing 5.0L Gi engines in wet slip with block drain hoses, is there a better way?

Monterey296Twin5.0Gi

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We are new to this boat and the previous owner used this flush system to run freshwater through both 5.0L engines after returning to the slip each time. We wanted to keep up the routine, but the block drain is a very small opening and we weren't sure if we could plumb those lines to another water port on the engine that could flush better, maybe on the thermostat housing? Or...

The old owner rigged up hoses and a Tee so he can flush both engines at the same time, but the parts are hokey and I'd at least like to do a better job or newer hose parts. Any ideas are appreciated.
 

alldodge

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Probably need to see what you have, and need to post some more before iboats will let you upload pics. Using a 3rd party place to like pics would help for now

Not much flushing is done with the block drains, my first thought is the original owner might have used them to drain the slat out before flushing with fresh, don't know right now
 

Monterey296Twin5.0Gi

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I think it is a factory arrangement from reading other forums, on the port engine it is also where the water heater connects one of its hoses to the block drain. There is a Tee there to allow the flush hose to connect too. Then the previous owner added a garden hose Tee between both flush hoses to each engine so he can fluch both at the same time through a hose run to an access hole above the swim step.

Here are some pics, the port block drain has the brass Tee to connect the water heater and the starboard block drain just connects to the drain hose:
https://photos.app.goo.gl/xUK6ZxdagFj3DaCU6

You can see what a small, like 1/4" NPT", hole it is, so I am not sure how much flushing water gets through or how long I should be flushing for. Some say that it won't get past the thermostat, but I assume some does before it cools to close.
 
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alldodge

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The water heater on my Formula was connected the same way, just the flush doesn't look like it would work very well, but just my opinion

Many use a Tee connection on the intake hose to the pump and switch then start the motor.

For others to see a few pics easier

20191223_151821.jpg20191223_151958.jpg20191223_151233.jpg
 

Scott Danforth

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I would invest in two neutrasalt injection systems from volvo, then add their flush kit.
 

Monterey296Twin5.0Gi

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Thank you both for the help,

I just discovered the Neutra Salt system that they sell.

Would I need one kit for each motor? Or can I "Tee" the hoses and just inject twice as long?

Do you know where it plumbs into on the engine?
 

Thalasso

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The flush needs to be before the raw water pump. This way you can run the engine .
Engine is only to be run at idle rpms while on the hose
Now on the nutrasalt system. If you don't boat in saltwater it's a waste of your money.
 
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Monterey296Twin5.0Gi

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I should specify the boat sits in a saltwater slip, so we need to be able to flush in water.

Thank you, I think I might get the parts to at least move the flush hose IN from the block drain on the side up to Tee off of the intake hose on the raw water pump. I see they descipe doing that here:

MOD EDIT

Can you explain if there is also a pump/impeller in the sterndrive? I am a little confused as I thought there was one in the sterndrive, also the raw water pump running off belts at front of engine, and also the Chevy-style water pump front/center of the engine. Do I have that right, 3 pumps?
 

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muc

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https://www.iboats.com/shop/perko-1-flush-pro-inboard-flush-valve-kit.html

I'm in Minnesota so I don't know much about flushing. (Mercury tells me that our lake water is better than the tap water in some parts of the U.S.) but the kit I posted a link to is the one that customers who "winter" in FL. (and have their boat transported south) have me install on their new boats. Don't know if that one is the right size for your engine --- check with whoever you buy from to make sure.

No Impeller in Volvo drives.
Most garden hoses have barely enough water flow to do one engine much less two.
The flush hoses that you have now was Volvo's 1st attempt. The photo with the blue cap is their 2nd attempt. Note that the blue cap MUST be tightened with a wrench.
I'm told that Nuetra-salt is better than nothing, but not as good as a proper flush. A proper flush takes at least 15 minutes.


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BRICH1260

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My last boat had a similar system. It basically had two water lines from a T connector entering the engine block on both sides at the flush port. Water from the tap entered both sides of the block and pushed the block and riser water out the drive of the boat. It was not designed to allow the engine to run during this time as it totally bypassed the water pump and intake.
 

QBhoy

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You could of course just take the intake hose off the inlet side of the raw water engine driven pump...stick a hose down it and run it for a minute or so.
 
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