Moderated Discussion Areas
  ContinuousWave: Whaler Performance
  13 dauntless-porpoising

Post New Topic  Post Reply
search | FAQ | profile | register | author help

Author Topic:   13 dauntless-porpoising
rkp posted 08-11-2003 01:55 PM ET (US)   Profile for rkp   Send Email to rkp  
I have a 95 13 dauntless with a 40hp johnson. The boat runs well overall but if I trim it up even slightly it porpoises. I have installed a Doel fin and get on plane quickly but cannot introduce any trim. Would trim tabs help and would they be a good idea on this size boat?


JohnJ80 posted 08-11-2003 02:37 PM ET (US)     Profile for JohnJ80  Send Email to JohnJ80     
Ah, we get this problem again.

Here is what you need to do:

1. Evaluate the vertical position of your motor. Odds are that if a dealer installed it, it is too low and probably on the last hole. You need to adjust this up and see if it works. Whaler recommends that the AV plate be 0-3/4" above the boat bottom. Experience on this forum seems to say that you need to be 1-1.5" up. Small changes (like one hole) make a big difference so you need to experiment.

2. Look at your prop. If it is Al and not cupped much you should consider going to a higher performance prop with more rake and cupping. This will help your motor stay 'hooked up' and push the boat over the lump of water that you keep falling off of.

3. You have already added a fin, but this interracts with item #1. basically, when the boat is on a plane you need to have the fin just at the surface of the water, and not below it. This is normally #2 but you alrady have it.

Trim tabs come next (last). Basically these are to position the attitude of the boat into the waves and then being able to somewhat decouple the motor trim from the boat trim. However, you should try all the other steps above first. You may (and probably will) get the result you need and want.

I really got into this and now have become obsessed with boat trim. I'm going to look hard at trim tabs for by Dauntless 15 because I am curious and now I want the handling trim to be perfect and totally controllable. Part way there doesn't do it for me anymore, part of it is the problem solving. But, as my wife tells me, I'm half crazy anyhow so consider the source.

Read this thread - its on my boat that I repowered - where I went through this whole journey. You can solve this problem and it will work very well would be my guess.


rkp posted 08-17-2003 04:10 PM ET (US)     Profile for rkp  Send Email to rkp     
I took your advice and moved it up one hole. It made a big difference and I am wondering if I should move it up another hole. How do you know if it is too high. I also put a wedge on. The only problem I am having with that is now the steering rod hits the transom in a hard right turn. Can't turn as tight but it is worth it with the performance improvement.
Sal DiMercurio posted 08-17-2003 06:15 PM ET (US)     Profile for Sal DiMercurio  Send Email to Sal DiMercurio     
You will know if the engine is to high because the prop will ventilate or blow out if you trim it or make a sharp turn.
Keep an eye on your rpms because raising the engine puts less drag on the engine & the rpms are going to climb more & more every time you raise it.
If your on the second set of holes, i'd go up one more & see how she handles.
If she vents real easy or blows out in turns or while trimming out the engine needs to come back down a set of holes.

Post New Topic  Post Reply
Hop to:

Contact Us | RETURN to ContinuousWave Top Page

Powered by: Ultimate Bulletin Board, Freeware Version 2000
Purchase our Licensed Version- which adds many more features!
© Infopop Corporation (formerly Madrona Park, Inc.), 1998 - 2000.