In-line flushing system

[granpafish]

Another question. Never had an I/O before and am mortified that engine is raw water cooled. I know that it is an established system, it is just that I've never had to deal with one that stays in the water. Can't teach an old dog new tricks. I see that there are several in-line flush systems that hook up directly to a hose and flush the engine. (not the lower unit) Does anyone have info or opinion on this? It seems to me that it would extend the life of the manifolds, risers, etc. quite a bit if they work as advertised. The one I was looking at is made by Perko. Thanks Granpa

 

[crazy charlie]

Re: In-line flushing system

Flushing your motor after each use is the best possible thing youy can do for your motor.And guaranteed your motor will show its appreciation along with his right and left arms the manifolds and risers.I have had several i/os raw water cooled and have flushed them all.I feel guilty if I dont.You must be very careful though.there are different ways of flushing and they dont all work for any motor.I have set up 3 different flush methods because each of my boats i have had require a different setup.What do you have?????Charlie

 

[granpafish]

Re: In-line flushing system

Charlie, thanks for the interest. It is a merc cruiser 5.0L EFI. There is a swim platform on the transom that pretty much eliminates the possibility of getting any muffs on the lower unit, and like you, I really feel a lot better if I can flush at least the system above the drive. The Perko unit is basically a T that fits into the intake line and has a hose attachment with a anti backflow valve. I saw it in a BoatsUS catalogue, but know nothing about it. Thanks Granpa

 

[crazy charlie]

Re: In-line flushing system

I saw the same unit but it cant be used on alphs drives for some reason.I thought the same thing about the swimplatform being in the way but that is the way i flush my twin 230 mercruisers.There is no room in the engine comp to add anything else.So i have no choice but to lay on my stomach and attach the muffs.What kind of acess room do you have by the motor???Charlie

 

[rodbolt]

Re: In-line flushing system

hello<br /> the alpha drives have a water pump in the gear case. you would have to rig a diverter to spray the water pump water overboard and use the fresh water to cool the engine. more trouble than its worth. next time by one with a full closed cooling not just 1/2 closed cooling and all this goes away.<br /> good luck and keep posting

 

[crazy charlie]

Re: In-line flushing system

Not so fast Redbolt,thats not the only way to flush.If Gramps has the room,I have the setup.Charlie

 

[granpafish]

Re: In-line flushing system

Charlie, It's a bravo 3 so I think the in-line would work. I have plenty of room under the box. Can you think of any other reason I should not try it? I'm a little afraid of it because it seems so easy and effective but haven't heard of anyone who uses one or even has a comment on it. Is it a new item? I guess it is the old "seems too good to be true" syndrome. I saw another flush system that has a manifold and 4 smaller hoses that reach out to risers, etc. and the main water hose attachment has to be mounted on the hull somewhere. Way too much happening there. It may get to more places but much more opportunity for things to go wrong. That and the fact that it is 4 times more expensive. If this Perko works, it would certainly sooth my old mind that is used to having a fresh water flush of my outboard and a closed system on the inboard I used to have. If you are flushing twin I/Os from the platform, I know that you are of the same mind and even more so. Does that make me Crazy Granpa? Thanks

 

[crazy charlie]

Re: In-line flushing system

Im sure we have both been called worse Gramps.It was my understanding that the perko was dewsigned for inboards with some io application.When i saw it was not for alphas,i stopped looking at it so I cant really say if it is good or not.I will reply again with the setup i made on my last single io so I have enough room to write it all.Charlie

 

[crazy charlie]

Re: In-line flushing system

I started out by removing the petcocks on the block.Just the twist part,leave the base.Clamp heater hose onto each one.Run the 2 hoses back to the stern and up to a T fitting.Run 1 hose off the T and install a water inlet some where outside the engine compartment.I had to drill one hole for the inlet.My inlet was in the rear of the cockpit.When I was done using the boat i would quick connect the garden hose to the water inlet and turn the water on very low pressure and just leave for a while.Simple!!!!! And no need to run the motor or open the engine compartment.the most important step is to use very low pressure to flush.A powerful flush would cause hydrolock--A big problem!So nice and easy with the water pressure and it was a great system.I dont have the room to do this now with twin V8s so its laying on the swim platform for me.Charlie

 

[granpafish]

Re: In-line flushing system

Wow, going from a gentle flush with a cockpit connection to doing twins lying on a platform is quite a difference. Look at it this way. You're doin some bad time now to assure yourself a ticket through the pearly gates. Can you give me some info on hydrolock? That's new to me. It sounds serious and something I would have discovered the hard way if you hadn't enlightened me to the term. I do appreciate you taking the time to educate me on these matters. Granpa

 

[crazy charlie]

Re: In-line flushing system

Hydrolock is when water enters the combustion chamber either through a bad manifold or riser or if forced through the valves (this only happens on motors with valve overlap)by flushing with too much pressure or leaving a flusher on full force without the motor running.The water fills the cylinder and gives the piston nowhere to go.The symptoms mimic that of a weak battery.The plugs have to be removed to allow the water an exit.There is sometimes damage due to the repeated attempt to start the motor and there is usually water in the oil.Bad news,so be careful.Charlie

 

[crazy charlie]

Re: In-line flushing system

I also had an electric oil changing pump mounted in the engine compartment connected to the drain at the bottom of the oil pan.the oil change would take me all of 3 minutes.I would only have to hold down a button as the oil was automatically drained into a container.I had that boat set up nicely.Now with twin motors my life has really changed.Charlie

 

[granpafish]

Re: In-line flushing system

Charlie, thanks for all your helpful info. I've learned a lot. Granpa

 

[rodbolt]

Re: In-line flushing system

hello<br /> with a bravo drive you have a belt driven or possibly a crank mounted seawater pump. no brovo had a pump in the gear case. to use the inboard type flusher you either have to buy the perko with a built in check valve or make and install a seacock between the seawater intake and the flusher. I dont reccomend any I/O or inboard to be flushed with the engine off. its asking for trouble and not doing anything to move sand or mud from the block. the t-stat wont open and you just cannot get enough water swirling through and the risk of forcing water in the manifold is just to severe. if you flush it and leave it and dont know that water is in the exhaust manifold we will call you a repower customer. we have enough problems with the guys that like to let the engine idle for 20 min then shut it off. those are always the guys with the rusted rings and stuck valves. by the very nature of camshafts and valves to make power requires a certain amont of valve overlap. meaning at low speeds some water mist is trying to head back to the cylinder. at low speeds the manifolds and risers are cool enough not to vaporize the moisture.so the guy that starts his motor and lets it idle for 20 min every week is actually killing his engine.merc tried to use sone restrictor balls that restricted the water to the riser at low speeds to force the riser to run hotter to try to keep the mist vaporized. Volvo and merc both reccomend letting the engine run about 1500 rpm for 5 minutes after extended idle then return to idle and shut it down. good luck and keep posting

 

[crazy charlie]

Re: In-line flushing system

Good info Redbolt!!! Charlie

 

[granpafish]

Re: In-line flushing system

Thanks Rodbolt.