View Full Version : Engine Rev after Run/Throttle

07-21-2008, 11:49 AM
The boat is a 88 prostar w/ the 351 and a 1:1 Trans.

After a run (wakeboard or skiing), the boat would go off plane, but would idle very, very high. Often times we would run the boat at about 3000 RPM, then putting the throttle back down, it would only drop down to 2000 RPMs.

The throttle cable was not sticking.

Does anybody have any ideas. I was thinking maybe the secondaries were sticking.

Any other ideas to check - some other ideas that friends through out where checking the transmission cable (but not quite sure what to check there) and the springs on the throttle cable - I wasn't sure if this was applicable since the throttle cable is manually moving the throttle body butterfly closed - but the spring is there.



T Scott
07-21-2008, 11:59 AM
You could have a vacuum leak around the base of the carb.

07-23-2008, 05:14 PM
How old is your PCV valve? If it sticks open, it'll really suck air and if you remove it completely, it will idle close to that speed.

07-30-2008, 07:36 AM
That's a good idea - I don't think I have ever changed it. I'm not quite sure how I overlooked that one.

I'll go ahead and change it and give it a try this weekend.

off the wall idea - could it have to do w/ the use of 10% ethanal gas in any way - and the engine heating up? Probably not since it would need to air w/ the mixture anyways...