Newb question: Starting the engine on dry land

[KooK]

1978 Correct Craft Ski Nautique

I need to fiddle around with the engine a little bit, it needs a good tuneup and I want to check a few things out. I was wondering if I were to hook my garden hose up directly to the fresh water pump if that would be sufficient to keep the engine cool?

Thanks.
-Aaron

[Captbob626]

You don't want to hook up directly. Get a hose and attach to the pump and let it suck out of a bucket. Put your garden hose in the bucket. Pressure could back water into the engine.

[TRBenj]

I would love to know the proposed path that would allow "pressure to back water into the engine". It is not a credible scenario.

The RWP will outpace the supply of just about any garden hose by a significant margin. The bucket trick is fine, but a bit cumbersome. Hooking the hose directly to the engine will supply all the water needed to cool the engine and keep the impeller lubricated since the engine is not under load, but you do run the potential to collapse the hose (and then run dry). A simple tee in the cooling path that allows you suck air as necessary to prevent a collapsed hose, while still providing cooling water is the way to go unless youre attempting to troubleshoot the cooling system.

[Rick]

If you hook the hose directly to the intake hose and turn the hose on full without the engine running there is 90PSI water pressurizing your cooling system. Water can be pushed through the exhaust manifold/riser connection if it is not 100% sealed. I agree with the T suggestion, I would put a hose on the T and put it a bucket that would relieve the pressure and reduce the air sucked into the system. You should be able to build the adapter for about $10 at Home Depot

[AirTool]

If you hook the hose directly to the intake hose and turn the hose on full without the engine running there is 90PSI water pressurizing your cooling system. ...

I've presented this argument several times and still people dis me about it. I don't care,...it's their engine.

To the op: no matter what you think about safety regarding your prop, do not put your transmission in gear. Your strut and packing are dry. Don't do it.

I didn't re-read Mr. Benj'n post,....if he wasn't clear...don't rev your engine....because your hose can't supply enough water at higher rpm. If you have to for your tune up, maybe replace your impeller after you are all done.

DanielC ? might quickly post a link to his invention/set up.

[jchamlin]

Just use the bucket method. Go to an automotive store and get a rubber tube. If you pull the water intake hose off the bottom of the hull (mine is very accessible), you can put the rubber tube into that and the other end into the bucket. Then put your garden hose into the bucket and fill it up. You'll be able to monitor the water usage and rev the engine a bit if needed. It's not a perfect scenario because the rubber tube (being a smaller diameter) may not be able to supply the cooling system with as much water as normal, but it works for me.

I prefer to use hull port because it goes all the way through the system and you can check for leaks.

[DanielC]

http://www.planetnautique.com/vb3/sh...ushing+adapter
Quick enough?

[TRBenj]

I've presented this argument several times and still people dis me about it. I don't care,...it's their engine.

To the op: no matter what you think about safety regarding your prop, do not put your transmission in gear. Your strut and packing are dry. Don't do it.

I didn't re-read Mr. Benj'n post,....if he wasn't clear...don't rev your engine....because your hose can't supply enough water at higher rpm. If you have to for your tune up, maybe replace your impeller after you are all done.

1. Please do not put words in my mouth. The engine can be revved up a bit without shredding an impeller. The water coming from the hose is enough to keep the impeller lubricated. Without a load on the engine, it will also fail to overheat even with the massive air leak.

2. 90psi from the hose being "forced" into the cooling system will not cause an issue. To suggest that it would indicates a complete lack of understanding of the boat's cooling system.

The RWP is capable of moving a lot more water than a hose can provide. Try running from a bucket if you do not believe me- you will suck it dry faster than you think. There are no hard blockages in the engine's cooling system that will allow pressure to build and go where it shouldnt, even with the engine running. If you are able to force water in and past the impeller, it will fill up the engine from bottom to top, then the exhaust manifolds, and then exit out the exhaust. This is the path of least resistance. Suggesting it will blow out a gasket somewhere is illogical. Saying that the water would force its way past the riser gasket and into the inner part of the manifolds (and into the cylinders) when the passages allowing the water to go up and out the risers and out the back of the boat makes no sense at all.

[ski4evr]

Has no one used one of these?
http://www.overtons.com/modperl/prod...0&merchID=4006
Granted, I don't rev the engine, but for warming up for an oil change, and pre trip inspecton, it has proved invaluable. At idle, there is still more water pressure available "spraying out of the plunger" than the engine needs. I have let it idle for more than 15 minutes in the driveway and never exceeded operating temp. Not recommending using one, but really like mine.

[DanielC]

The "toilet plunger" type of water supply works.
Be careful, sometimes if you get in the boat, it can fall, and quit suppluying water to the boat, and if you are in the boat, your first clue that happened is the engine getting hot, and your raw water impeller is long gone bad by then.

[bhectus]

If you hook the hose directly to the intake hose and turn the hose on full without the engine running there is 90PSI water pressurizing your cooling system.

Wat?!?!? Where do you live that you're getting 90psi in a residential neighborhood? Put a hose pressure gauge on your bibb and I bet it is more like 45-60.

[Mikeski]

Every boat I own gets a T between the fresh water pickup and raw water pump (before strainer). The T gets a valve and hose fitting. Excess water/pressure goes out the bottom of the boat until until it is started and the raw water pump pulls in what it needs. Totally simple, self modulating, and cheap. Not sure why anybody does anything different... ever. Why bother with buckets and excess hose, more stuff to go wrong.

By the way, I just redid my sprinklers and just measured 85PSI of water pressure with the regulator wide open. I regulate it down to 75PSI so it is constant and does not modulate lower if a couple neighbors turn water on.

[countiemountie]

I like the "red neck" method that someone posted a while back using a garbage pail. I installed the Perko flusher on mine, however the issue that I run into is that my cottage's shallow water pump can barely keep up with the engine's draw.

[2001SAN]

Every boat I own gets a T between the fresh water pickup and raw water pump (before strainer). The T gets a valve and hose fitting. Excess water/pressure goes out the bottom of the boat until until it is started and the raw water pump pulls in what it needs. Totally simple, self modulating, and cheap. Not sure why anybody does anything different... ever. Why bother with buckets and excess hose, more stuff to go wrong.

By the way, I just redid my sprinklers and just measured 85PSI of water pressure with the regulator wide open. I regulate it down to 75PSI so it is constant and does not modulate lower if a couple neighbors turn water on.

I have used the bucket method also. As said already, the RWP out pumps the garden hose big time. I keep a few spare 5 gallon jars full while I warm the engine up which is really awkward. I like this idea. Got a pic?

D.

[Mikeski]

I think you can see it on my wakeboard boat. I simply replaced the 90 degree fitting going into the strainer with a T and put a hose fitting on the new port. When I want to flush it I pull the plug hook up a hose and turn on the water. The water pours out the bottom of the boat through the intake grate until I start the boat. Once it is running it pulls in what water it needs or all of it. It may not supply enough water to feed the raw water pump at 3000 rpms but it supplies enough water to keep it cool and lubricated with zero chance of running a bucket dry or a fake-a-lake slipping off the bottom of the boat (I have had that happen twice).

The fittings on my direct drive slalom boat are easier to see but I don't have any pictures yet.

ps. save any comments you may be inclined to post about my Simer pumps in the motor compartment. I know all about it and don't recommend it. I even have the ignition proof Johnsons on the shelf to replace them but I have not had the time yet (and may never take the time to actually swap them out).