115 merc "tell-tale" not consitent

[mrclean12]

Hi all,
I have what i believe is a 1965 115hp inline six mercury. I noticed water being very intermittent coming out of the tell tale exit in the cowl. I thought maybe it was a bad impeller. I took the lower unit off & inspected the impeller...looks like new! So then i thought maybe there was some foreign material plugging it. I found nothing. When I blow compessed air into the tell tale outlet it then works for maybe 15 seconds as well as if I raise the rpm'sit also works for a short time. The power head stays cool enough to hold your hand on the cylinders so I know its getting some sort of cooling. Any ideas how to make this work again? Thanks in advance guys!

 

[Moody Blue]

Re: 115 merc "tell-tale" not consitent

An inspection of the impeller is sometimes not enough if you don't know what to look for.

Even though it may look "good" it may be no good. The fit between the impeller and the S/S cup is very important. The impeller material can take on a "set" preventing the vanes from operating properly. Small wear groves in the S/S cup can significantly affect the efficiency of the pump.

For the cost of a replacement impeller, it is generally recommended they be replaced every two years.

 

[Wingedwheel]

Re: 115 merc "tell-tale" not consitent

If the last time the impellor was replaced and nothing else was, it could be a worn face-plate. I would think while you have it apart, get a kit and replace all the components.

 

[oldgradywhite]

Re: 115 merc "tell-tale" not consitent

I would r&r the water pump and I would also check the tube where the water comes out of. Mud wasps have blocked my tell tail on my stack 6 before.

 

[mrclean12]

Re: 115 merc "tell-tale" not consitent

Okay guys. I'm going to order a pump kit. I went to the lake over the weekend & it worked though. It wouldnt work @ home with the muffs on it though???