Has Problem Using Flushing Earmuffs

[jaykchan]

I have a problem using any flushing earmuff kit to flush the lower unit of a Mercury Marine 115hp outboard motor in a 1995 Laguna. When I ran the motor with a flushing earmuff kit, the motor overheated even at 1000 rpm (I shut it off at 170 degree), and I didn't see the telltale water stream coming out either. When I ran the motor in a small water tank, the motor ran fine and didn't overheat, and I saw the telltale sign. Strangely, I have tried three different versions of flushing earmuffs kits (one is the one from QuickSilver that is specifically designed for the Mercury motor), and I have exactly the same problem. This tells me that the flushing earmuff kit didn't work well, or it was not mounted correctly, or the water pressure was not enough.<br /><br />Obviously, I can simply live with using a small water tank. But using a flushing easrmuffs kit should be faster and easier than using a water tank. The reason is that I need to pre-fill the water tank and dump the water afterward, and I need to keep re-filling the water tank while I am running the motor. Therefore, I really want to find a way to use the flushing earmuffs correctly.<br /><br />Instead of doing things that may risk overheating the motor or damaging the impeller in the lower unit, I would like to ask around here before I do anything that will hurt the motor:<br /><br />- Should I expect to be able to use a flushing kit wth a Mercury outboard motor?<br /><br />- How do I test the impeller (to see the telltale sign) without actually running the motor?<br /><br />- Any tip in mounting a flushing kit correctly in a Mercury outboard?<br /><br />Thanks.<br /><br />Jay Chan

 

[Laddies]

Re: Has Problem Using Flushing Earmuffs

It sound like low water pressure on the hose you are using to flush with

 

[rodbolt]

Re: Has Problem Using Flushing Earmuffs

use the standard city water pressure, some well water systems are not enough, and turn the hose valve wide open. using a 3/4" hose helps as well. 1/2 and 5/8ths sometimes just wont flow enough water.

 

[DHPMARINE]

Re: Has Problem Using Flushing Earmuffs

I can't answer you,but will give the following :<br /><br />Boss has a 40 Yamaha on a Tracker.When he goes to the ocean,we flush it when he comes home.<br /><br />Even after a new water pump,motor would not pump on the flushette.Still does in a bucket.Go figure.<br /><br />DHP

 

[Silvertip]

Re: Has Problem Using Flushing Earmuffs

You cannot tell the condition of the water pump impeller by looking at it (unless it is in pieces) -- especially since you can't see it unless its removed -- in which case it would be silly to go to that trouble and not install a new one.

 

[tashasdaddy]

Re: Has Problem Using Flushing Earmuffs

when you put your ear muffs on do you have water leaking around them. if you don't you don't have enough water pressure

 

[JoeW]

Re: Has Problem Using Flushing Earmuffs

Jay,<br />I have the same problem on my 1988 Mercury 100hp, even after a brand new impeller and after trying three different kind of muffs. I have over 50 lbs of water presure and water comes out of all sides of the muffs. I never get the tell-tail outlet stream either.<br />I've simply resolved to never start the motor out of the water. I'd be very interested if you find a solution to this problem.<br />-Joe

 

[Silvertip]

Re: Has Problem Using Flushing Earmuffs

With 50 pounds of pressure and water squirting out all around the muffs, you may be creating a void behind the muffs where the pump doesn't get any water. You do not need full force water pressure for any engine on muffs. If its blowing out around the muffs, turn it down some.

 

[Clams Canino]

Re: Has Problem Using Flushing Earmuffs

If it's blowing out around the muffs, it won't be once it's running. - in general.<br /><br />-W

 

[jaykchan]

Re: Has Problem Using Flushing Earmuffs

Thanks for all the replies that I have received.<br /><br />I am sure the water faucet has enough water pressure. I used it to run two water sprinklers --in serie. I reduced the water flow to avoid damaging the impeller in the lower unit. Now, I am not sure if I might have overdone this by reducing the water flow for too much.<br /><br />Glad to hear that the impeller may still be OK even if I cannot see the telltale sign when I use the flushing earmuffs adapter. I was afraid that the impeller may be bad. Now I think about this, the impeller should still be good; I saw the telltale sign when I run the motor in a small water tank. Good. One fewer thing to fix.<br /><br />When I use the flushing earmuffs adapter, I see water coming out from mainly the "forward" side of the adapter. That area has a depressed area on the surface of the lower unit where the water intake holes are; the depressed area probably is designed for getting more water to go into the water intake holes when the boat is cutting through the water. This means the earmuffs cannot have a good seal on that depressed area. This explains the reason why water is coming out from that area. And this may also mean that there is not enough water getting into the water intake holes in the lower unit. I would like to know if other members in this forum have the similar depressed area in the lower unit, and if they have any problem using the flushing earmuffs adapter. If this depressed area is going to prevent me from using the flushing earmuffs, I will have to stick with using a small water tank.<br /><br />Jay Chan

 

[wunderman]

Re: Has Problem Using Flushing Earmuffs

I use a100 gallon rubbermaid tank i had laying around on my merc 150 I leave it in neutral. my boat has a water pressure gauge it will tell when that impeller goes , mine said zero, then my over heatbuzzer went off. that 150 lower unit is heavy on mine.

 

[MercFan]

Re: Has Problem Using Flushing Earmuffs

I turn my tap wide open. It sprays water all over the place while the engine is off. As soon as I start up the ear muffs are sucked to the intake and the spray past the muffs reduces to a trickle.