On Tue, 05 Aug 2003 20:47:30 -0500, "
wrote:

I have a 30 hp johnson that will not flush with ear muffs. I destroyed
three water pumps so far. I have replaced the thermostat also. I use
tape on the two top vent holes in the foot when attempting to flush with
ear muffs like the manual says. I have twenty five hours on it and it
has a strong tell tale flow when running.
If you use ear muffs it overheats quickly and melts down the water pump
impeller. I now use a 30 gallon drum to immerse and flush it with and
and works fine. I have twenty five hours on the motor now and it runs
well. The overheating alarm never comes on unless I try to flush with
earmuffs. The water flow and pressure is good through the hose. I have
checked and rechecked and am at a loss for what the problem is.
Any ideas?
Thanks in advance.
Warren


I use flushing muffs on both of my Johnson outboards, V4 80hp and V4
130 hp, and my Mercruiser Alpha 1 130 hp outdrive with no problems.

The only time I have had a problem is if you run the engine at more
than a fast tickover which can cause the impeller to try to suck more
air than water.

Before starting the engine there should be a good flow of water from
both the tell tale and exhaust ports using moderate hose pressure.

It could be that you dont have the muffs lined up properly, or that
hose pressure is failing.

Hope this helps

John

Thanks for your reply, I do check very caref ully the alignment each
time. I have had 6 boats so I am not a novice(just telling you this for
info) so I am sure they are on correctly. I have purchased new earmuffs,
tried a different hose and even taken the boat to my office and
attempted to flush it on that faucets water supply with the same
results. I have not inverted the seals on the shaft with excessive
pressure nor am I running the engine above an idle when this happens.
Idle speed is about 800rpm. This has every mechanic I know stumped. I
now have 35 hours on the engine and it performs flawlessly otherwise. I
did find a small piece of a previous water pump lodged at the tell tale
water exite pipe. I was able to unscrew the fitting and remove it. I
flushed all the water channels with the water pump off and the
thermostat removed. I found no other debris. I still use the 30 gallon
drum to flush with (chicken after 3 water pumps) Again I check and
recheck the hose not to be kinked and water flow to be strong enough.
I dunno, I think I will just have to live with it the way it is until I
decide to replace the water pump. Then I will try muffs again one last
time. Thanks for your reply.
Warren


Racker wrote:

On Tue, 05 Aug 2003 20:47:30 -0500, "
wrote:


I have a 30 hp johnson that will not flush with ear muffs. I destroyed
three water pumps so far. I have replaced the thermostat also. I use
tape on the two top vent holes in the foot when attempting to flush with
ear muffs like the manual says. I have twenty five hours on it and it
has a strong tell tale flow when running.
If you use ear muffs it overheats quickly and melts down the water pump
impeller. I now use a 30 gallon drum to immerse and flush it with and
and works fine. I have twenty five hours on the motor now and it runs
well. The overheating alarm never comes on unless I try to flush with
earmuffs. The water flow and pressure is good through the hose. I have
checked and rechecked and am at a loss for what the problem is.
Any ideas?
Thanks in advance.
Warren



I use flushing muffs on both of my Johnson outboards, V4 80hp and V4
130 hp, and my Mercruiser Alpha 1 130 hp outdrive with no problems.

The only time I have had a problem is if you run the engine at more
than a fast tickover which can cause the impeller to try to suck more
air than water.

Before starting the engine there should be a good flow of water from
both the tell tale and exhaust ports using moderate hose pressure.

It could be that you dont have the muffs lined up properly, or that
hose pressure is failing.

Hope this helps

John