Mercury 4.5 2-stroke -85 no cooling, impeller changed (pics and video)

modopopcorn

Seaman Apprentice
Joined
Jan 18, 2013
Messages
46
Hi!

I've bought a Mercury 4.5 this weekend and after getting it up and running I noticed that there isn't any water coming out of the peehole.

The first thing I did was to change the water pump and as expected it wasn't pretty... some pieces of the water pump came out when I removed the lower unit and the pump house.

With the new water pump installed and everything put back together and still no water comes out of the peehole.

I took apart the water pump again and found that there was a bit of rubber from the old pump blocking the intake, I took my blowgun and blew in the hose to the peehole, it came air from the feedingtube and I though that it would work now that I've cleaned out the intake.

Nope, still no water from the peehole, from what I can tell there's not blockage in the feedingtube and I can't figure out what to do.

I also hooked up the lower unit to a power drill and the the water pump seems to be working, it's not that much of pressure but I don't know how much RPM I get from the power drill either.

I tried connecting a hand pump to the hose to the peehole and pump water backwards through the system and it seems to be working as it should. I haven't tried from the feedingtube as I don't want to push possible blockage further into the engine.

Video 1

I'm all out of ideas and really need help to solve this problem.

Thanks in advance for any advice that could help me.
 

modopopcorn

Seaman Apprentice
Joined
Jan 18, 2013
Messages
46
Isn't there anybody who can give any kind of advice? I thought Iboat was the best forum on the internet for this kind of problem but maybe not..

Anyway, I've removed the powerhead and the exhaust manifold. From what I can tell there's nothing blocking the water, perhaps the blockage came loose when I removed the powerhead, I can't see that there should be any problem with the cooling now, guess I'll see later today when I have the time to put everything back together.
 

Chrsamss

Seaman
Joined
Jul 7, 2009
Messages
54
Your feeder tube might have a crack in it and the water is not reaching the powerhead, I had this problem with my '92 115hp merc. Put compressed air into the P hole and cover your feeder tube with your hand, see if you have a leak Good luck
 
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