5.7l Cobra impeller question

[Stankbait202]

Does the drive have to be fully submerged all the way past the impeller for it to pump? Seaswirl Spyder 202 - 5.7L Cobra. Just rebuilt motor (and new impeller/housing, plate etc) and lake tested with all the back seat and rear platform out of the boat..nothing but engine in the back. Also about 1/4 tank of gas. Its getting too hot at idle but did fine while under way. all passages clear no leaks detected anywhere. At home I ran it in a bucket (big Rubbermaid tote) water was just above the entry holes and I felt some suction but not enough to get it to the motor. Doublechecked the impeller housing all good-spinning the right way, seals are good, vent hose hooked up. Now I'm thinking the lighter load brought the drive out of the water just enough to keep it from pumping. Am I correct to assume this? I didn't know to check this while at the lake but after some research Im thinking that may be the problem. Just looking for some reassurance. Its about to drive me nuts. haha

 

[bruceb58]

It needs to be submerged for it to work. Obviously, it won't be submerged when you are on plane but the force of the water into the intakes forces it up to the impeller.

The fact that it is too warm at idle is not good. Have you pulled off the hose to the thermostat housing to check flow when you are in the water at idle?

 

[Stankbait202]

Not yet - taking it back out today to check it out...

 

[wcasey5]

I would suspect the water inlet tube seals. They are prone to drying out causing an air leak. You have to separate the top and bottom of the drive to replace the seals.

 

[Stankbait202]

Well it worked great....once I put all the weight back in and took it out never got over 175. I did take the hose off the thermostat housing and look for flowage. It shot out with about a 4" head, shut it down, hooked it up and ran the hell out of it. Good to go. Thanks for the technical and moral support everybody.