Flush kit for Mercruiser

[lenny2113]

I have twin 350 Merc setup on my boat. Would like to get some feedback on how to go about flushing the engines after each trip. In the past,I have seen some people hook up a garden hose to some kind of setup in the bilge and run on fresh water hose for a few minutes. I am not talking about muffs to the lower unit water intake. I can't reach outdrive water intake holes, otherwise would use muffs for flushing. <br />I cannot find a kit for this purpose. <br />Does anyone have a solution?<br />Any marine place that sell kits like this, or maybe someone have a "do it yourself" idea?<br /><br />Thanks,<br />Lenny

 

[Fishermark]

Re: Flush kit for Mercruiser

It depends on what drive you have. My 5.7 Mercruiser has a raw water pump on the engine with a thru hull pick up. They sell kits to flush the engine(s) with this set up. (I also have a Graco basket strainer, and to flush my engine I just take the top off of the basket strainer and put a garden hose in it - after closing the valve on the hull fitting).<br /><br />If you have a Bravo drive, I understand that the Leg simply serves at the "straw" to pick the water up instead of the going thru the hull.<br /><br />Are you talking about flushing it on a trailer, or while still in the water?

 

[lenny2113]

Re: Flush kit for Mercruiser

I have Alpha 1 drive, which also picks up raw water and brings it to the engine. <br />Thanks Fishermark, you have made it clear to me what I have seen other people do. <br />How do I do flushing with my setup (Alpha 1) I still have no idea. <br />The boat is in the water.<br /><br />Thanks

 

[Fishermark]

Re: Flush kit for Mercruiser

I don't know how you would do that in the water - someone will chime in shortly I'm sure. I would suppose you could splice a "Y" valve of some sort into the inlet hose coming from the transom assembly and add a fitting for a garden hose. You would then need to divert the water coming from the lower unit overboard. But I'm just thinking out loud now. (Usually not a good thing to do! )

 

[RatFish]

Re: Flush kit for Mercruiser

There is at least one after market device that will allows you to flush your engine while still in the water. It's made by MST Guardian . I installed one this past spring because I occasionally use my I/O boat in salt water. Read through the MST web site. They have a lot of info about the flush device along with a lot of marketing BS. I paid about $260 at one of their dealers, so you can see they are not cheap. I'm sure you could buy just one and rig it up to flush one engine at a time.<br /><br />EDIT: You can flush while in the water because you do not start the engine. This link shows how the device hooks up to an engine.

 

[zzzzz]

Re: Flush kit for Mercruiser

Howdy ! what you need is a Perko (brand) "Flushpro"..it comes in various hose sizes and is installed on the incoming line from the drive...complete installations instructions in package...about $75...maybe even find on iboats

 

[RatFish]

Re: Flush kit for Mercruiser

Make sure you search the Boating Forums for comments on the Perko Flushpro. I seem to recall complaints about it breaking.

 

[crazy charlie]

Re: Flush kit for Mercruiser

Lenny,I installed a set up that worked great on a 5.7 alpha.You need to have room to get to the block petcocks.I replaced them with barbed brass fittings and ran heater hose off of them and connected them with a y fitting going into a single length of heater hose and ran that up to the rear of the cockpit to a water outlet fitting with a cap on it.I would remove the cap and put a quick connect on it each time i used the boat and let hose water run in at low pressure for the time it took me to clean and close up the boat.Worked great.Unfortunately my current boat has twin v8s and I dont have the room to put that kind of setup in so I bring my drives all the way up and lay on the swim platform ,roll up my sleeves and reach down and slip on the muffs.I insert an ice pick through one side of the muffs and into the intake so they dont slip off.Its a pain ,but it is surely worth it.Charlie

 

[lenny2113]

Re: Flush kit for Mercruiser

charlie,<br />I also have a twin with no room at all. It is so limited on space that I have to use a mirror for things like changing spark plugs. I would have to pull the engine to reach the bilge pump, unless someone lowers me in on the winch vertically, head down I will look into Perko Flushpro.<br />I also have no swim platform as I have thru-hull exhaust in place where it could be. Can't reach drives and do not flush now. Still need solution to get it setup for easy flush...<br />Thanks to all.

 

[crazy charlie]

Re: Flush kit for Mercruiser

I was thinking of hiring a midget or a capable 6 year old to get in there.I believe the perko specifies that it is not for alpha or mercruiser applications.Check it out ,I may be wrong but I dont think so.It drives my crazy if I dont flush the motors.I have never let them go a day without a fresh water flush.Charlie

 

[Cool It]

Re: Flush kit for Mercruiser

I have a question if you guys dont mind me chiming in. I have been flushing my engine with Muffs--5.0 mercruiser alpha one-- now you got me wondering even though I put the muffs over the water intake holes is the water pick up hose still taking in raw water or are the muffs covering that also????<br /><br />Thanks<br />COOL IT

 

[RatFish]

Re: Flush kit for Mercruiser

Cool It,<br /><br />If the muffs fit correctly, then you will be fine.

 

[crazy charlie]

Re: Flush kit for Mercruiser

CoolIt,if your drive has a pump in it that directs the water to the motor then what you are doing is fine.If you have a sea water pick-up pump that brings the water in then you are doing nothing by putting muffs on the outdrive.Charlie

 

[tommays]

Re: Flush kit for Mercruiser

charlie<br /><br />Take it from me,I learn things the hard way. Charlie<br /><br />i think i understand how you had a problem getting water in your motor useing a hose now from the other post <br /><br />tommays

 

[lenny2113]

Re: Flush kit for Mercruiser

I looked at both products suggested ("Perko FlushPro" and "MST Guardian"). On the twin setup I don't think it would be possible to use one flush kit for both engines. "Guardian" is good but would cost $500 for 2 units. Perko FlushPro is unexpensive and is simpler to install. <br /><br />Here is my concern about Perko: <br />Perko setup is simple. Basicaly you cut the hose that brings water from the outdrive to the engine and install the FlishPro unit inline. The unit <br />has a valve on top which will close raw water from entering into engine while the garden hose is attached to the flush kit. <br />Question: Raw water pump Impeller is pushing water into the engine, but the water pushed in does not exit anywhere. This creates back pressure. Any known problems with this?<br /><br />Thanks to everyone for replying and sharing your opinions. <br /><br />Lenny

 

[AaronG]

Re: Flush kit for Mercruiser

I just bought a flushpro for my 5.7 Merc w/ Alpha 1 drive. I had the same question as Lenny2113. I figured you ran the hose with the engine off. <br /><br />Anyone know for sure?

 

[lenny2113]

Re: Flush kit for Mercruiser

AaronG,<br />Eather way is OK. Engin OFF or ON.

 

[garycinn]

Re: Flush kit for Mercruiser

Lenny,<br /><br />Did you buy the flushpro and install? How did it go?

 

[AaronG]

Re: Flush kit for Mercruiser

What happens to the water the lower unit's water pump is pushing up? That ws my concern. I'll probably just run it with the engine off

 

[Chris1956]

Re: Flush kit for Mercruiser

Aaron and others, It seems to me that the rubber impellers in the Alpha I outdrive (and outboards) would not be damaged by the backpressure. On outboards and I/Os the cooling water is recirculated until it becomes warm enough to open the thermostats for discharge. This means that the impellers are designed to supply a variable amount of water to the motor. <br /><br />Alternatively, you could let the impeller pump the saltwater into the bilge of the boat while you are flushing the motor. The bilge pump can pump it out, and then after the motor is finished flushing, put fresh water in the bilge to clean out the salt water.