OUTLAW EAGLE MANUFACTURING

Chrisco · Joined: 12 Apr 2013 Posts: 32 Location: Stony plain

I installed a new SS 5.7 impeller into my AT 312 and now I seem to have a growling noise at idle. the noise was not there before with the AL 5.7 imp. as soon as you bump up the throttle the noise is gone, the boat still performs well with no other problems. poss shimmed to tight ???? mabe someone can shed some light.

shallowman · Joined: 03 Apr 2006 Posts: 199

Nope not to tight , it is the weight of the stainless impeller vs/Alum.
that is a normal noise , , what most times cause that growl is that the impeller is heavy and the flex plate is light so the noise is coming out of the universal joint ,until u get more load on the impeller , true, thats why i run a flywheel vs flexplate , more mass ,
hope this helps you and it won't hurt anything

Chrisco · Joined: 12 Apr 2013 Posts: 32 Location: Stony plain

Hay thanks..... I just talked AT and that's what they said to. Fuck thought my boat was coming apart. thanks for the help !!!

ALEX · Joined: 02 Aug 2005 Posts: 176 Location: red deer

The noise at idle is usually spline rattle ...it can be reduced by select fitting a yoke with longer splines on your driveshaft and using blue permatex sealant on the splines.
To eliminate it you can go to a driveshaft with fine splines in the middle section and bolt the yoke solid to the pump shaft ..as is done on some race boats.The disadvantage is you have to move your motor ahead and go to 4 point mounts

Chrisco · Joined: 12 Apr 2013 Posts: 32 Location: Stony plain

Willl it hurt anything if left like it is ??