Possible Blocked Water Channel on 70HP Johnson Need Advice

[SouthCarolina1]

Buddy at work has a 1999 Johnson 70HP that 99% of the time is in salt water. He told me that he went to start his motor up for the first time this season and it was not peeing water. I told him it probably just needs a new water pump, I'll order the parts and you bring your boat by with some cold ones. I also ordered all the parts to replace his thermostat. Order of events:

1) When I went to install new thermostat I found that there was no thermostat, springs, little plastic housing, etc. Glad I order everything.
2) Installed new water pump kit. Started the motor and it was still not peeing. Pulled the pisser tube off the nipple of the exhaust housing and no water came out of the fitting.
3) Dropped the foot and found that the o-ring that goes between the housing and flat metal plate had blown out. At the time I thought I had installed it wrong even though I put some sealant to hold it place. Reinstalled the water pump. With the foot still off I put the muffs on it and watched the water flow out. No leaks around housing. Reinstalled foot.
4) Started the motor again, no peeing. Pulled the thermostat cover off and started the motor. Water poured out of the thermostat housing... I am thinking the blockage caused the o-ring to blow out of the water pump housing.

Am I right thinking the motor has a blocked water channel? If so, is there any kind of acid solution that I can pour into the thermostat housing or the nipple coming off the exhaust housing? The blocked water channel has to be in the exhaust housing, should I pull the exhaust cover plate off?

 

[flyingscott]

Saltaway and garbage can. Keep track of the temps while it is running in the garbage can. If that doesnt work you will to start taking it apart to find the blockage.

 

[SouthCarolina1]

Ok so I dropped the foot and plugged the water inlet tube at the bottom of the mid-section. I took the plastic nipple off the exhaust housing and thermostat cover. I poured vinegar down both openings until the system was full. I let it set for a few hours and removed the plug. I then took an old garden hose I have, cut it, and clamped it over the water inlet tubing. I got water gushing out the thermostat cover. Reinstalled the thermostat cover and then I got water coming out of the exhaust housing opening for the plastic nipple!!! I then installed a Sierra 18-3389 water pump kit, new plastic fitting, and new hose. Motor is peeing but its not a consistent stream. I have attached a picture. I noticed three locations where water was coming out of. The bracket at the bottom of the steering arm and midsection has water coming out of it and my main concern is water is spraying out the small hole between the midsection and foot. I mean it is jetting out. The water pump kit came with three O-rings. One o-ring was obviously for the water pump housing. But there was a small thin o-ring and a small thick o-ring that I have no idea where they go. The parts diagram for the motor does not show these O-rings. What did I mess? Where do these O-rings go?

 

[SouthCarolina1]

[No message]

 

[oldboat1]

+1 on post 2. Let it idle in a garbage can. Sink it deep and keep the hose running. Monitor temps.

Can't test the system on muffs (water spurting out is a result of hose pressure).

 

[jbuote]

Not a pro, but another +1 on post 2...

Also, I know it's a different engine, but on my 50ESL71 when I run on muffs, I get water out some of the same places..
Marked up your pic to show what is "Normal" for my engine.. At least I'm to understand It's all good on mine..



Not sure if "My Engine" (1971 50hp) normal applies to the engine you're working on (1999 70hp), but thought I'd share anyway just in case...

Hope it may help.. :noidea:

 

[SouthCarolina1]

Ok well that is good to hear. I have never seen the motor run on a boot so I do not know what to compare it to. I appreciate the input.