Seacock for I/O?

[sasto]

Another thread got me wondering...as I am somewhat new to I/O boats. Appears not all have any means of closing off the raw water intake to the motor, as in a seacock. I am used to having a seacock and have depended on them in several occasions. I ran my 1st I/O yesterday, a Volvo Penta V8 in a Chaparral. Boat goes on lift, hose her off, no big deal then....how do I flush the engine and outdrive.

 

[user64]

Re: Seacock for I/O?

I had a VP 5.0 attached to an sx drive. No seacock either. Water was drawn thru the sterndrive and up to the engine mounted impeller. Flush it with muffs if you store it dry or an a trailer. You can buy flush kits that install on the engine and are T 'ed into the raw water supply if you keep it in the water. Think Tempo makes some but do a search.

 

[tkrfxr]

Re: Seacock for I/O?

You need to know the cooling system. If you tell us the engine model number, closed or raw water cooled, you may get a good response on how to flush it...

Volvos frequently come with engine flushing kits that permit running the engine with a garden hose...like this kit sold for engines that do not have one installed at the factory:

http://www.marinepartsexpress.com/engine_flush.html

 

[sasto]

Re: Seacock for I/O?

Thanks for the info guys. The question is more general than specific to this one motor, but I am looking into installing a flush system in this case.

 

[jerryjerry05]

Re: Seacock for I/O?

If you have a Volvo the T in the line will help flush but you need a way to shut the water to the drive off.A BIG ballcock will work.You want nothing to restrict the flow to the motor.
Otherwise the water from the hose will just go out the back. I have seen the Volvo raw water pumps suck a garden hose FLAT.They really pump a lot of water so watch the speed on the motor,Anymore than an idle can do that. J

 

[captk]

Re: Seacock for I/O?

Most sterndrives have a seawater pickup, or waterpump, in the gearcase, so they do not have a seacock. Some sterndives do have a thru hull seawater pickup and those have a seacock, or should have one.

 

[tkrfxr]

Re: Seacock for I/O?

Thanks for the info guys. The question is more general than specific to this one motor, but I am looking into installing a flush system in this case.

Well, the kit I referenced above costs $18.34 plus S&H.

I hope it comes with instructions on use...

My engines manual warns not to flush at above idle speed (I don't know why you would want to). If you are troubleshooting your engines, and need to raise RPMs, you should probably do it in the water, not through a garden hose.

Other warnings that are not in the manual:

1. The hose cap must be closed (when not used for flushing) to prevent air from entering the cooling system on the raw water side. This can cause impeller damage and can lead to overheating by pushing air through the heat exchanger, manifolds and risers....

2. If using the flush system on a raw water cooling system, beware of where the connection is....Volvo has some engines configured with the hose AFTER the seawater pump, so the system gets flushed with the engine off. The inlet hoses are not flushed in this setup. If you leave the cap off, you will get a bilge full of water AND overheat you engine...


It still matters what model engine you have....

 

[sasto]

Re: Seacock for I/O?

I am used to a seacock and an inboard strainer. Serves two purposes for me. The seacock is turned off when maintaining the strainer or other in water repairs or maintenance needed to be done to the raw water coolong system. I also have another valve between the seacock and strainer, or engine, which has an attachment that runs into the bilge. In case of catastrophic hull failure the seacock is closed, the "crash valve" opened, the engine draws its water from the bilge and out the exhaust. Can also be used to flush engine. I would like a seacock, with a strainer, and an easily maintained raw water pump on my engine. Am I asking for to much?

 

[tkrfxr]

Re: Seacock for I/O?

I am used to a seacock and an inboard strainer. Serves two purposes for me. The seacock is turned off when maintaining the strainer or other in water repairs or maintenance needed to be done to the raw water coolong system. I also have another valve between the seacock and strainer, or engine, which has an attachment that runs into the bilge. In case of catastrophic hull failure the seacock is closed, the "crash valve" opened, the engine draws its water from the bilge and out the exhaust. Can also be used to flush engine. I would like a seacock, with a strainer, and an easily maintained raw water pump on my engine. Am I asking for to much?

It CAN be done, and I'm sure it has been done...

Separating the water intake from the outdrive is only a matter of hose and seacock....Take a hose coming from a strainer and connect it to the inlet port of the engine's raw water pump....

It may or may not matter that the outdrive does not sent the cooling water to the engine....I would defer this to experts and may depend on which drive you have, or if the drive itself gets cooling from this raw water circulation....

I have seen threads on this site asking this question, but rarely seen the poster come back to tell us how it worked out....I recall someone doing this and adding a drive shower to a merc outdrive to assure drive cooling...

-Good luck.

 

[sasto]

Re: Seacock for I/O?

She is a 2007 5.0 Volvo Penta to an SX outdrive. After further review this boat does have a flushing system similar to the one shown. The hose connection is on the transom. The raw water hose comes from outdrive, thru a steering cooler, to the flush T, then to pump. I assume the outdrive will backwash with the engine not running and hose connected? This boat is on a lift with an integrated swim platform.

I assume this outdrive dosen't have an impeller? I better go to school... I know very little about I/O's

We built a 28' CC with a 300hp 6cyl. Yanmar diesel coupled to a Bravo 3 and we did run raw water over the top of the outdrive for a cooling problem they were having at the time. I don't recall any raw water coming from the outdrive, but I do know we used a thru hull raw water intake system.

Thanks for the advice, interesting to me.

 

[jerryjerry05]

Re: Seacock for I/O?

No pump in that drive.It's for water pickup.J

 

[tkrfxr]

Re: Seacock for I/O?

She is a 2007 5.0 Volvo Penta to an SX outdrive. After further review this boat does have a flushing system similar to the one shown. The hose connection is on the transom. The raw water hose comes from outdrive, thru a steering cooler, to the flush T, then to pump. I assume the outdrive will backwash with the engine not running and hose connected? This boat is on a lift with an integrated swim platform.

I assume this outdrive dosen't have an impeller? I better go to school... I know very little about I/O's

We built a 28' CC with a 300hp 6cyl. Yanmar diesel coupled to a Bravo 3 and we did run raw water over the top of the outdrive for a cooling problem they were having at the time. I don't recall any raw water coming from the outdrive, but I do know we used a thru hull raw water intake system.

Thanks for the advice, interesting to me.

-Good! you have a flushing adapter... When you open the water hose, the water flows backward through to the pickup holes in the outdrive. When you turn on the engine, the water pumps forward through the system...

-The outdrive does not have an impeller...Volvos never do. Your impeller is inside the engine-mounted raw water pump.