Running w/ Ear Muffs

[LSUTIGERS74]

I attached the ear muffs to the lower drive unit with the water hose turned on and placed them over the little gils that pick up the water, when I cranked up the engine, no water would circulate back out through the exhaust. Could this mean that my impeller is shot? I know this is my new boat and I have been around boats alot but I am not turning something on that allows the water to flow through the engine?? I just got the boat today and brought it home to check out the engines once more, it is a 1990 Donzi Black Widow w/ twin 460/ King Cobra's. Can someone shed some light onto this situation?

[onesubdrvr]

Sounds like the impellers to me, or, check your earmuffs and make sure they are sealing good, I just recently replaced an impeller, and had to do it again because I was loosing too much water around the edges. I was using the rectangle muffs, changed to round, seem to work MUCH better than the rectangles ever did. And oh yeah, it takes less than 2 minutes without moving water to fry the impeller, more like 45 seconds!!

Wayne

[Dr. Dan]

:smash: Well, I am just guessing here, I have a single King Cobra 1993 22 Classic, ah...not enough water pressure from a normal house Garden Hose?

On a single engine, it can take 30 to 45 Seconds to maybe get some flow through a bone dry cooling system... but running two Big Blocks that is a horse of a different color... if you didn't have impellor problems, you might now?

Just my $.02

Doc :smash:

[gcarter]

A small thing that most don't think about is, how much water can you get through a 5/8" hose? Not very much. Probably only about 5 GPM.
One thing that can help is a 3/4" hose. They're expensive, I paid about $60.00 for mine at Tractor Supply. Anyway they can flow maybe 12 GPM. It still probably not enough, but it's a step in the right direction.
I think most seawater pumps will flow about 35-50 GPM at cruise speed, so it's easy to understand why hoses are only good for running at idle.

[RedDog]

Hold the muffs with your hands over the intakes until the system "primes." That gives a better seal. You'll get a little wet at first but at least you are sure the water is entering the drive and not all just spraying around the edge. I suspect the KC impellor is more durable "dry" than the Merc impellors. Plus the KC impellor is real close to the water intake.

[LSUTIGERS74]

Bringing up the issue on the seal. My ear muffs didn't appear to seal up at all b/c water was going everywhere. Should the seal be good enough so that no water should leak out at all?

[LSUTIGERS74]

Well decided to take a 55 gal. trash can and submerge the lower unit under water and see if it would run that way, of course now I can't get the engine to crank, I will switch out batteries tomorrow and see if it cranks, it seems like it is trying to turn over and fire off but just can't get enough juice.

[onesubdrvr]

Bringing up the issue on the seal. My ear muffs didn't appear to seal up at all b/c water was going everywhere. Should the seal be good enough so that no water should leak out at all?

Some is unavoidable, but, running, there should be nearly NO leakage!! if there is, you don't have a good seal.

I'll be running my boat tomorrow, if I think about it, I'll video the leak rate of the good sealing muffs. And, for what they cost, it's probably not a bad investment to replace every year, I know I will be now.

I don't have a KingCobra drive, but I do have a Cobra,...

Wayne

[onesubdrvr]

Well decided to take a 55 gal. trash can and submerge the lower unit under water and see if it would run that way, of course now I can't get the engine to crank, I will switch out batteries tomorrow and see if it cranks, it seems like it is trying to turn over and fire off but just can't get enough juice.
Make sure your fuel tank valve is fully open, check all your plug and coil wires. Also, if engines have been sitting, may need carb rebuild / cleaning. Remember, always start simple, then work to the more complicated things. May need to check your timing too. Engines even out 180* in timing will attempt to start,....

Just some ideas, good luck, and keep us posted

Wayne

[LSUTIGERS74]

The boat has been sitting up a while, but it fired right up this afternoon when I was originally trying to get the water to run through. I think the batteries may have just gotten drained down over the course of the day.

[22zxla]

tiger, sorry to hear about the problems so quick. Takes some joy out of the excitement of new boat.Wish i had some answears but cant help you. Sounds like water pump,but could also be a hose kinked in water intake. My friend had that problem. Curious how fast the tempature gage is rising, guess youll know when it gets running.Look at the bright side TIGERS WIN!

[Sam]

When using muffs I always duct tape them to the drive just to make sure I get a good seal. Since I started doing this I have had no problems.

Sam

[joel3078]

I have King Cobra drive - use the round muffs and turn the garden hose up all the way. Wiggle the muff ears around with the engine off till ya get the least amount of water blowing past the round rubber muff ears. Also make sure you don't have a bunch of water leaking past the barb fitting on the plastic garden hose connector that goes into the muff ear. All this stuff has to be tight and in good condition or the KC drive won't get enough water. If in doubt, get a new muff - hell Walmart even has em.

When my boat is running there is very little water leaking in the muff area and it takes 15 seconds or so before water comes out the exhuast. Again this is at idle speed or a little above. Oh ya, make sure the drive is in neutral, a spinning prop will tear the hell out of that brand new muff ya just bought and you'll have a pretty ding in your prop. :bawling:

[FISHIN SUCKS]

My King C takes a while(sometimes over 1 1/2 min) to draw water using muffs and always has. It has never hurt my impeller and water is getting to the impeller. All of my seals have been replaced, just takes a while. Once the water starts coming out the pipes, she's just like old faithful. I figure my Big Blocks' just got a Big Bladder!:D

[LSUTIGERS74]

I finally got the engine to crank this afternoon by giving a bump to the throttle, guess it just needed a little more juice to ignite. The good news is that the water actually flowed out through the exhaust so the impeller is working, althought the water was a little rusty colored. Just needed to be run some to get the gunk out, but is running fine now. Thinking maybe MSD ignition kit might help the engine crank up easier from throttle idle position. Also if i would have sealed up the ear muffs better I believe it would have worked also.

[LSUTIGERS74]

I finally got the engine to crank this afternoon by giving a bump to the throttle, guess it just needed a little more juice to ignite. The good news is that the water actually flowed out through the exhaust so the impeller is working, althought the water was a little rusty colored. Just needed to be run some to get the gunk out, but is running fine now. Thinking maybe MSD ignition kit might help the engine crank up easier from throttle idle position. Also if i would have sealed up the ear muffs better I believe it would have worked also.

Next project is later today, I still have the problem with the starboard engine. Which if you will see my post on "Oil and water in pan" you will get the jist of the problem that lays ahead, b/c the engine is still frozen up. I will be pulling the plugs this afternoon and bore scoping the engine in the morning. Hoping it is just a blown head gasket or a bad riser, will just have to see.

[22zxla]

Tiger good to see your hard to work getting that boat back together. Just wanted tosay that offshoreonly.com is also a good site for performance boaters. Pretty big site with plenty of topics an has a donzi section. Hope that helps you in any way.

[DickB]

I bought my Donzi in the winter, well past the last opportunity to take a test ride. The seller agreed to my holding final payment until after a checkout ride in the spring. We did so in April, only a few days after ice out. "Running w/ Ear Muffs" is exactly what we did during that checkout ride.

[Barry Eller]

A small thing that most don't think about is, how much water can you get through a 5/8" hose? Not very much. Probably only about 5 GPM.
One thing that can help is a 3/4" hose. They're expensive, I paid about $60.00 for mine at Tractor Supply. Anyway they can flow maybe 12 GPM. It still probably not enough, but it's a step in the right direction.
I think most seawater pumps will flow about 35-50 GPM at cruise speed, so it's easy to understand why hoses are only good for running at idle.
High RPM's will fry a King Cobra waterpump impeller. As gcarter states, not enough water flow to the pump if it is spinning at high RPM's. Idle speed only when on the hose. Run the engine at high RPM,s and you will see smoke coming from the water pump cover. I know from experience. This is what 3000 RPM's will do to one. I was adjusting my choke, and clearing out a too rich condition, you know "blowing it out"!!! Water stopped coming from exhaust and smoke coming from pump cover on outdrive.

[LSUTIGERS74]

The engine works fine now, I changed out the spacer and the gasket for the Holley Carb this morning and saw that I had flooded the engine with gas. Also once the gas evaporated out of the engine and installed new plugs this morning, the beast fired up and sounded brand new. Although the color of the water coming from the exhaust was less than ideal, it was jet black, but eventually ran clear, yalls input was greatly appreciated on this subject matter.