no water threw telltale with new impeller bt did on first start up!!!!! help

[khalidow]

hi i just installed a new impeller to my 200hp mercury blackmax
water was peeing great with muffs only when revved up after installation !!!

took out to local lake for test only peed strong when revved hard

week later went out for the day only steam and little spitting of water in lake while ridding

came home removed poppet valve and cover, started motor for a few second and water comes out threw block


refitted poppet valve with cover and removed pipe going to starboard thermostat, water was was coming out but not flowing was throwing water out. like spitting action but strong amounts

removed pipe going to port side thermostat before thermostat and water also coming out there also spitting

removed pipe from tell tale no water comes out pipe only steam

blowed in pipe which connect to tell tale, blows clean air comes out by exhaust holes

removed pipe from tell tale that attached to block more less where throttle cable is no water coming out there too!!

on top of motor between the two cylinders there is like a outlet used for water pressure gauge open that up water comes at strong while idling...

and also while revving motor up water comes out threw the two top exhaust
holes just on top of leg / under cowl is that normal????

thanks in advance i really wanna take her out later

[Turbodiesel]

Pretty normal on those engines. The tell tale is controlled by the thermostat. So it will pulse and also be very hot!

[khalidow]

but at the moment no water is coming out the tell tale while running or idling

[khalidow]

and i tested it without the thermostats still no peeing

[khalidow]

can nobody help me??

[Turbodiesel]

Did you say you had water coming up through each head while the Thermostat covers were off?

[khalidow]

Originally Posted by Turbodiesel

Did you say you had water coming up through each head while the Thermostat covers were off?

yes water coming out

[khalidow]

thermostate do open when i test them in hot water aswell

[Turbodiesel]

Lots of water? have you checked all the pipe work to make sure its not blocked up?

[khalidow]

checked all the pipes nothing blocked used compressor to blow out, lots of water does come out the more i rev the faster it shots out

[Turbodiesel]

DO you get an overheat alarm? It sounds like its ok to me. The telltales do pulse on those engines and they do run hot!

[uncle al]

Robby the grommet could be split and partialy blocking the water tube on the top of the water pump, we have both seen that in the past

[khalidow]

i should have a alarm in the control box right, doesn't sound off....

[khalidow]

Originally Posted by uncle al

Robby the grommet could be split and partialy blocking the water tube on the top of the water pump, we have both seen that in the past

u talking about the impeller housing ????

[Turbodiesel]

Good point Uncle Al.

[uncle al]

Kalidow Yes inthe water pump housing what happens is when they are not put up straight with a bit of marine grease on the grommet to help it slid in it cuts a piece out of the grommet restrickting the water flow, when you put the g/housing up there should be some mastic across the back of the water pump between the exhaust to stop exhaust gases getting into the flow of water.Also the water pump should be pushed home by hand and NOT jacked in with the fixings nuts or bolts

[m chappelow]

Any chance the impeller could be slipping on the shaft
Key way or even the impeller hub Itself that's seperated from the rubber part as can happen on some cheaper replacements

[uncle al]

m chappelow the only way it would slip on the drive shaft if the keyway has not been fitted or slipped out puting it together,as for the rubber impellor slipping on its hub not a known problem but one worth checking,

[m chappelow]

Originally Posted by uncle al

m chappelow the only way it would slip on the drive shaft if the keyway has not been fitted or slipped out puting it together,as for the rubber impellor slipping on its hub not a known problem but one worth checking,

Or if a rusty or slightly corroded key has perhaps been put back in place
,with regards to the hub/rubber separation I have in the past come across a few faulty new ones especially the ones with bronze hubs .

[dgpw]

If you disconnect the three cooling pipes the 2 at the top of the block (one on each cylinder bank) and the one at the bottom I think you will find that the bottom one will be pouring water and the top 2 wont. When it is hot the stats will open and the top 2 will work. It could take up to 20min to get hot enough to open the top stats at idle. The other thing is that depending on the hose flow at your house you might not get enough coolant in to get it to work correctly try a barrel.