How to correct for torque steer?

[henryb]

Ok, I need to understand how this all works! My boat has some serious torque steer issues. I have installed an extended ride plate based on Aquamans design (thank-you it works fantastic for eliminating porpoising). However I can not seem to get it to correct for torque steer?

On a nice calm day, my boat pulls to the left by a significant amount. So I adjusted the left side of the ride plate lower as suggested somewhere in these pages. However it doesn't seem to correct the problem at all? I even tried lowering right side, thinking the it would make it turn like a slalom ski? But really no difference! My adjustments were fairly significant, 6-7 full rotations more then the other side.

Can somebody chime in who has had success with this or can explain what might be happening?

 

[Coastiejoe]

I don't recall the exact details, but I am pretty sure I read where you can add what is basically a skeg. Also, you may have a bad cable that is allowing the nozzle to flex due to thrust. If so, and it is common, you can't fix without replacing the cable assembly.

 

[henryb]

Thanks Joe, I think you might have something there... a Skeg mounted in the center-line of the hull approximately mid-ship... much like an Inboard has. Do you know of anyone who has done this successfully? This would have to be a bolt-on type of mounting, I would think?

I was afraid that a stretched cable might be the issue when adjustments on either side did not seem to do the trick on the extended ride plate! That is also probably hard to prove/test? If it turns out that a new steering cable is required... where can you get one? I'm guessing Seadoo would charge an arm and a leg?

 

[henryb]

So I've seen brand new replacement steering cables for about $140(US). I was just wondering what kind of a job it is to replace one of these... Is it a do-it-yourself job? I know that it runs almost the full length of the hull with very little access to most of it's length.

 

[RiverPro]

Ok, I need to understand how this all works! My boat has some serious torque steer issues. I have installed an extended ride plate based on Aquamans design (thank-you it works fantastic for eliminating porpoising). However I can not seem to get it to correct for torque steer?

On a nice calm day, my boat pulls to the left by a significant amount. So I adjusted the left side of the ride plate lower as suggested somewhere in these pages. However it doesn't seem to correct the problem at all? I even tried lowering right side, thinking the it would make it turn like a slalom ski? But really no difference! My adjustments were fairly significant, 6-7 full rotations more then the other side.

Can somebody chime in who has had success with this or can explain what might be happening?

Was the craft pulling B4 you installed the extended ride plate? / What year is it?

 

[henryb]

Yes, it had this problem before I installed the extended ride plate. My boat is a 2000 Seadoo Challenger 1800, with an M2 210HP.

 

[RiverPro]

Okie Dokie-
Just after 2000, Merc updated the nozzle (not the steering vector) to compensate for the drift. I'll post a picture later.

 

[henryb]

Ok, so is this something that can be retrofitted, or is a new cable going to do the trick?

 

[RiverPro]

First, we must verify what nozzle you have. If the steering moves freely lock to lock, I doubt it would be cable. (But I have been wrong B4)

I going to take pics of both nozzles. Are you where you can post a pic of yours?

 

[RiverPro]

Double Post

 

[RiverPro]

Nozzle Offset

Look closely at the two nozzles. The offset compensates for the drift.

 

[henryb]

Very interesting, it's hard to see the difference on my phone. I will take a loser look tonight when I get home on a big monitor. I will be up at the cottage tomorrow and take pictures.

 

[RiverPro]

For the life of me, I cannot figure out why my posts are taking so long to load. I hit reply and the screen goes blank, thus I have no idea if my post has been successful.

 

[henryb]

Yes your posts are coming through. Is there a part number for the offset nossle, in case I have the centered version?

 

[henryb]

Ok, I can see that your "arrows" are slightly offset from one nozzle to the other. But it is not clear in the photo what they are pointing at? Can you clarify on what to look for on the nozzle when I get there tomorrow?

 

[henryb]

Ok, so are you saying that the "hole" in the nozzle is not actually drilled out in the "center" of the nozzle, but drilled slightly "offset"? Thus the side-wall of the nozzle will be thicker on one side from the other?

 

[Coastiejoe]

That is the first offset nozzle I have seen. Rather simple fix.

 

[henryb]

So, I would need to get one of these? Part number?

 

[RiverPro]

That is the first offset nozzle I have seen. Rather simple fix.

Merc introduced the 4 degree nozzle offset (Sept of 2000) because there was a fairly consistent steering pull on hulls with the larger engines and 4 blade impeller. This didn't seem to be a problem on the 175 Hp.

I will post part numbers in a bit, gotta run...

 

[RiverPro]

Offset part# 878080 / HOWEVER, that is not the same as the casting number on the part itself.

 

[henryb]

Ok, I will run it by the marina I had it serviced at and see how much they have it at. Thx a ton for this "insider" info... How in the world did you know about this?

 

[RiverPro]

Ok, I will run it by the marina I had it serviced at and see how much they have it at. Thx a ton for this "insider" info... How in the world did you know about this?

I checked on Mernet and the part is active, however un-available at the moment.

How did I know this? For the last 15 or so yrs, I have worked with only SJ`s, it is my job to know these things...

 

[henryb]

Well that would certainly put you in the expert category! Thank you for this morsel of great information!

I called the marina, they are available in the warehouse for $477. Ouch, that might have to wait til next year... already dropped quite a bundle on the boat this year so far. Maybe I will keep an eye peeled for a good used one online... or if you know someone that might have one? Let me know.

Thanks again, great info!

 

[henryb]

I have the replacement "offset nozzle" (thank you RiverPro), I will be attempting to install it today. Any words of wisdom on doing this swap?

 

[henryb]

Well, it appears that those bolts can be on there really tight! As I found out yesterday! No amount of pulling with the longest wrench I had and even banging the end of the wrench with a hammer (to get that impact driver effect) would loosen those bolts. Dang! Might be a job for a longer helper-pipe to extend the length of the wrench or an actual high torque air impact driver... None of which I have at the cottage!