Water tube replacement?

I replaced the water pump on my 1998 johnson 115. J115tsxecm. Pump was 2 years old and in decent shape. I run in salt water so figured it would be good measure to replace it. Motor never overheated before I installed new pump. Motor now overheats with muffs on it in driveway. So I figured I installed impeller or something in water pump wrong. I used all new parts in water pump rebuild. So 4-5 attempts to reinstall water pump engine still overheats. I followed manual for my model of engine to make sure all gaskets are in right place and impeller fins are facing right direction and used gasket maker. Tell tail is flowing fine. Removed thermostat and all though it is corroded it opens up at right temp. I'm in the process of installing new thermostats, gaskets and springs to rule that out. Water from tell tail is getting extremely hot and so is both cylinder heads.

Unless water pump is installed wrong which I really hope not as I followed schematic for specific engine model only other thing I can think of is something may have got lodged in water tube slowing down flow of water.

Do do I have to lift motor to install new water tube. Or can I just pull old one out put new water tube back in?

is there anything I'm missing here? And other possible reasons why after I installed new water pump engine overheats?

i feel like a fool cause everything was fine before I installed new water pump. I try to do everything myself following Manuel so I learn as I go. Hope I can fix this one.

was sealer used on replacement pump? You might have to remove l/u again and inspect water tube placement. Place a garden hose directly on water tube with a clamp and inspect top of water tube for leakage inside of middle housing using a flashlight

I allways test the pump before installing into the leg. use a chunk of hose two hose clamps and a drill with a socket the same size of the driveshaft. Allways spin the driveshaft clockwise and just submerge the drive in a barrel of water past the top of the pump and spin the shaft with the drill. water should gush out with plenty of pressure. Next remove the thermostat and adapt the hose to the water tube and see if water flows free out the thermostat hole. You need to pull the powerhead to install the water tube properly.

Before you go to extreme measures, put the boat in the water and see if you really do have a problem. You cannot test a water pump by running on muffs. When you are doing that, the water pump only allows water to pass through as it rotates. It is not actually pumping water. Nor does it have the normal exhaust back pressures on it.

What kind of drill do you use to spin a V4 impeller as my 1/2 drill wont do it as its 300rpm and it just oozes out the top???...got the t-shirt

A hole hog probably wont work well for high volume put your finger on the hole I bet it builds up good pressure. Only 300rpm its time for a new drill.

I have never had to test a repaired pump.-------They are so simple that there is no need to do the extra testing work !

Could I submerge motor in a plastic container instead of taking boat to lake? Its just a lot of work going to the closest lake which is 40 min away.

motor ran fine before with muffs on it in driveway with old water pump

Also there is a little hole between the motor and the lower unit. Not sure the purpose of it but i didn't fill it in with gasket maker as i figured it was there for a reason. Water does flow out of that hole when the muffs are on in drive way. The hole is in the front of the motor facing the boat between lower unit and motor. I would assume the hole is not to be filled in with gasket maker and is there for a reason?

Am I right on leaving the hole open?

kimcrwb1 still want to know what kind of drill turns the drive shaft on a v4-v6 outboard

Update

i installed new thermostats to eliminate those as a possible problem. The old ones all though corroded when I tested them they opened and closed same as new thermostats when tested in a pot of water and thermometer. springs seemed fine and gaskets looked good. Still did complete rebuild of thermostats Anyways.

Ran water though water tube as I suspected the water tube could have been clogged or damaged causing engine to over heat. When I ran water through the water tube it exited from where it would enter the thermostats, as at the time I had thermostats pulled off for replacement. Is middle housing between motor cover and part of the motor the crank shaft runs through?

I I have not been able to just test the new water pump I installed. Looking for a way to just test that. Lower unit it still removed from motor.

I was was going to reinstall lower unit and run motor in tank to see if motor still overheats. When I tested motor before I ran the muffs on it. I'm opting for a tank test as a posted stated is better and to now to be sure water pump is actually pulling water up through water tube. Before I reinstall lower unit is there anything else I can test for?

Not sure if this is related but my motor does run rough at idle. I figured it was a fuel problem cleaned out the carbs twice and second time I replaced the idle and low speed carb jets. Motor still runs rough. The longer I run the engine the worse it gets. Not sure if these problems are related. Just figured I would throw it out there

tha is for the help guys. I reall appreciate it

Read thread #2 entirely,you can run motor without lower unit installed to testpump

Wow that's awesome. Yes I missed that when I read ur post to begin with.

Well guys I don't know what I did right and what I did wrong but after new thermostat, old one worked when I tested it in water same as new one, I have a running motor that doesn't overheat. One thing I did different was run the motor in a tank as instead of on the muffs like a poster suggested. Thermostat was a absolute bitch to get in with minimal clearance for the thermostat itself and removing the screws as well because of the lower engine cover which is removable only if u pull motor, which I wasn't going to pull motor to make thermostat a cake walk.

i am so happy to have a motor that doesn't overheat now after I feel like I screwed it up in the first place, replacing the water pump for good measure when the old one was in good condition.

i appreciate all the input u guys gave me and read every post and attempted every suggestion u guys gave me.

thanks again. Mission accomplished!!!!!

happy boating and good luck