GT 40 not running at full power
Printed From: CorrectCraftFan.com
Category: Repairs and Maintenance
Forum Name: Boat Maintenance
Forum Discription: Discuss maintenance of your Correct Craft
URL: http://www.CorrectCraftFan.com/forum/forum_posts.asp?TID=36897
Printed Date: November-17-2024 at 1:37am
Topic: GT 40 not running at full power
Posted By: finnz
Subject: GT 40 not running at full power
Date Posted: July-30-2015 at 1:30pm
| I have a 1998 nautique with the GT40 it has been running great all summer long. I replaced the battery a couple of weeks ago and it has not run at full power since i.e., it does not seem to plane off as fast as it should and i am only running at about 38 mph at full throttle with just me in the boat (i verified via gps to eliminate a potential speedo issue). Normally at full throttle it is running 45-47mph and takes very little time to get there. I just figured that it was the fuel filter so i replaced it as-well, but still the same issues. Also, only running at a max of 3800 rpms or so. Any thoughts or ideas? |
Replies:
Posted By: JoeinNY
Date Posted: July-30-2015 at 1:51pm
|
Use a timing light or test light to check that you are getting spark on all 8 cylinders (alternately and more dangerously unhook one wire at a time to see if it makes a difference. If you are getting spark to all 8 then do a compression test. If all 8 have even compression then get a fuel pressure gauge. Do these things in that order ... ------------- http://www.correctcraftfan.com/diaries/details.asp?ID=1477 - 1983 Ski Nautique 2001 1967 Mustang 302 "Decoy" http://www.youtube.com/watch?v=cO5MkcBXBBs - Holeshot Video |
Posted By: finnz
Date Posted: July-30-2015 at 1:57pm
| thanks joe |
Posted By: Bri892001
Date Posted: August-03-2015 at 8:57am
| Do you have Perfect Pass on this boat? |
Posted By: finnz
Date Posted: August-03-2015 at 1:28pm
|
yep |
Posted By: Toertel
Date Posted: August-03-2015 at 1:42pm
|
I changed cap, rotor, plugs and coil last Friday and tooke the FAE off. Before she would run 43,5 mph After that, I ran out of lake at 46.6 mph with the ACME 668 All together a 200$ invest and did the trick! (Thanks to Nautique Parts, who sent the coil last minute via overnight and safed the weekend) ------------- 1994 Sport Nautique |
Posted By: Bri892001
Date Posted: August-03-2015 at 7:44pm
Make sure the servo motor is taking up all of the slack in the throttle linkage. It is supposed to do this as part of the initialization when the key is turned to on. Your recent battery replacement makes me suspect something is amiss electrically. Your PP needs a full 12 volts to initialize properly. Any slack left in the throttle linkage will give symptoms similar to what you describe. Essentially the throttle will not be opening all the way. |
finnz wrote: