!972 Mercury 75 won't pee

[alfshead]

I have a '72 mercury 7.5 HP outboard. It stopped peeing the other day and I have disassembled the lower housing and checked the impeller (from advise on this site). It is working fine, I checked as many hosing parts as possible and haven't found any blockages. So where to next?
Also does this motor pee when out of gear? The impeller only seemed to turn when the prop was turning?
Cheers.

 

[mrallen007]

Re: !972 Mercury 75 won't pee

I'd start with a simple hose check. If it's been working and all of the sudden stopped, checking for a blockage is your best first step. I hear a good long piece of weed eater line is good for this. Run it up the discharge hose and see if you can work out any blockage.

As far as the neutral question, my prop always runs. It does not have a true neutral. So, I can't really say whether it should or not.

 

[hotrod53]

Re: !972 Mercury 75 won't pee

The impeller turns all the time, it is driven off of the drive shaft which is directly off of the motor and before the fwd-N-rev gearing. Since the impeller is $10, and the impeller cup is $6, I'd replace it all. Your impeller key isn't goofed up or missing is it?

I would also look for a blockage or a broken hose, The pee hole is a plastic line that comes off of the block. If it's broken, the water can run inside the case and not out the hole. I am told that some outboards have thermostats too, they don't pee until they warm up, not sure if that is yours though.

Also, an outboard tech recently told me to never use oil or grease as the manuals say when installing a new impeller, use dishwashing liquid.

 

[hamrhal]

Re: !972 Mercury 75 won't pee

If the impeller is good and the housing is OK try running the motor with water to it and while its running shoot a blast of compressed air into the pee hole. May dislodge any debris in there.

hal

 

[alfshead]

Re: !972 Mercury 75 won't pee

Hi, I have tried cleaning all the tubes with the weed eater line and I now get good flow some of the time!!
It has a good flow of cold water then seems to reduce until it is very hot and then I get a good flow again, this repeats - I suspect a thermostat problem - Does anyone know if this model had a thermostat and how to remove it?

Cheers