Anonymous
01-22-2003, 10:36 PM
Mike
1. 20' Open Trolling Speed
My 20' Open has a 302, and the slowest I can troll is about 5 knots at 700 rpm. I think I'm trolling too fast for my live bait and want to slow her down a bit.
Would adjusting the idle do the trick, or is there a better idea.
Please let me know, I bought the boat a month ago and am constantly impressed.
Mike
Date: 03:44 p.m. on 04-11-2001
Prior Engagement
premium member in standard member. 2. Re:20' Open Trolling Speed
Mike - Check out this post (Trolling Speeds futher down the board). I do not think idling much below 700 rpms is going to be feasible unless you got that baby super tuned.
http://www.fishtheclassic.net/cgi-bin/UltraBoard/UltraBoard.cgi?action=Read&BID=3&TID=539&SID=3264
Good luck.
--------------------------------------------------------------------------------
Fair seas and tight lines,
Mike N.
Date: 05:28 p.m. on 04-11-2001
Capt Big Daddy
normal member in standard member. 3. Re:Re:20' Open Trolling Speed
I checked for the paper work on my trolling valve but they gave me none. my boat trolling speed is about the same as yours around 5 mph but with the trolling valve you can slow it wright down to a stop slow trolling for stripers and flounder is no problem.
Good Fishing Capt Big Daddy (Frank/VA)
Date: 08:24 a.m. on 04-12-2001
Leprechaun
premium member in standard member. 4. Re:20' Open Trolling Speed
Capt. B. D. - tell us more about the trolling valve. Is this an add-on module that's external to the box or an internal mod? Because as you are probably aware, the Shamrock 20 has a relatively shallow bilge and that's the reason that Shamrock never put a reduction gear trans in there, only the direct-drive 1:1 box will physically fit. I know many of the big New England-built downeasters up here on Long Island use a trolling valve because between the latent torque of a 400 hp diesel and the huge wheel they swing, there's no other way to slow those boats down, even at idle. An interesting subject.
That having been said, I think any Shamrock 20 can be slowed down, with proper carb adjustment/tuning and perhaps the addition of a supplimentary ignition box, like the MSD6 - the 20 should be able to creep along at less than 3 knots. Gotta get that idle WAY down around 475 rpm. Its perfectly possible, I do it with my 26 and I'm working with a much bigger prop, albeit with a 1:1.52 reduction gear.
Also consider that this extra-slow trolling situation can only occur under certain conditions, for example a perfectly flat ocean with no waves or tide, or running down-tide where the boat would be going a couple of knots even out of gear. Don't forget, in that circumstance, when you turn for a return pass, you will have to throttle up a bit to compensate for that tide or wave action that's now on the bow. I've taken her up as high as 1100 rpm to compensate for detrimental conditons and even at that throttle setting I'm only going around 3 kts. What I'm saying is that trolling speed is dependant on many factors, only one of which is the boat's actual ability to throttle way down.
Razor sharp tuning is a major key.
Rgds, Leprechaun
Date: 09:13 a.m. on 04-12-2001
Mike
5. Re:Re:20' Open Trolling Speed
Thanks for the feedback everyone, I do have a MSD on the engine and will see how far I can idle her down tomorrow.
We'll be trolling most of the day so I'll have some time.
Thannks again!
Mike
Date: 08:23 a.m. on 04-13-2001
Pottsie
6. Re:20' Open Trolling Speed
I've always had the same problem down here in S.Fla. Flat days sometime result in no current. You want to cover some ground, but don't want to drown your live baits. The answer is: Go spend 30 bucks on a sea anchor and spin the engine at a normal idle. Sure, your engine has to work a little harder, but you will find that you have much better control than trying to maintain a heading at 400 rpm.
Date: 12:07 p.m. on 04-25-2001
Bill
7. Re:20' Open Trolling Speed
I drag a 5 gallon spackle bucket with a rope behind my 20" WA. Slows her down to 3 knots but I wonder if that giant teaser scares the fish!
Date: 07:11 p.m. on 04-25-2001
1. 20' Open Trolling Speed
My 20' Open has a 302, and the slowest I can troll is about 5 knots at 700 rpm. I think I'm trolling too fast for my live bait and want to slow her down a bit.
Would adjusting the idle do the trick, or is there a better idea.
Please let me know, I bought the boat a month ago and am constantly impressed.
Mike
Date: 03:44 p.m. on 04-11-2001
Prior Engagement
premium member in standard member. 2. Re:20' Open Trolling Speed
Mike - Check out this post (Trolling Speeds futher down the board). I do not think idling much below 700 rpms is going to be feasible unless you got that baby super tuned.
http://www.fishtheclassic.net/cgi-bin/UltraBoard/UltraBoard.cgi?action=Read&BID=3&TID=539&SID=3264
Good luck.
--------------------------------------------------------------------------------
Fair seas and tight lines,
Mike N.
Date: 05:28 p.m. on 04-11-2001
Capt Big Daddy
normal member in standard member. 3. Re:Re:20' Open Trolling Speed
I checked for the paper work on my trolling valve but they gave me none. my boat trolling speed is about the same as yours around 5 mph but with the trolling valve you can slow it wright down to a stop slow trolling for stripers and flounder is no problem.
Good Fishing Capt Big Daddy (Frank/VA)
Date: 08:24 a.m. on 04-12-2001
Leprechaun
premium member in standard member. 4. Re:20' Open Trolling Speed
Capt. B. D. - tell us more about the trolling valve. Is this an add-on module that's external to the box or an internal mod? Because as you are probably aware, the Shamrock 20 has a relatively shallow bilge and that's the reason that Shamrock never put a reduction gear trans in there, only the direct-drive 1:1 box will physically fit. I know many of the big New England-built downeasters up here on Long Island use a trolling valve because between the latent torque of a 400 hp diesel and the huge wheel they swing, there's no other way to slow those boats down, even at idle. An interesting subject.
That having been said, I think any Shamrock 20 can be slowed down, with proper carb adjustment/tuning and perhaps the addition of a supplimentary ignition box, like the MSD6 - the 20 should be able to creep along at less than 3 knots. Gotta get that idle WAY down around 475 rpm. Its perfectly possible, I do it with my 26 and I'm working with a much bigger prop, albeit with a 1:1.52 reduction gear.
Also consider that this extra-slow trolling situation can only occur under certain conditions, for example a perfectly flat ocean with no waves or tide, or running down-tide where the boat would be going a couple of knots even out of gear. Don't forget, in that circumstance, when you turn for a return pass, you will have to throttle up a bit to compensate for that tide or wave action that's now on the bow. I've taken her up as high as 1100 rpm to compensate for detrimental conditons and even at that throttle setting I'm only going around 3 kts. What I'm saying is that trolling speed is dependant on many factors, only one of which is the boat's actual ability to throttle way down.
Razor sharp tuning is a major key.
Rgds, Leprechaun
Date: 09:13 a.m. on 04-12-2001
Mike
5. Re:Re:20' Open Trolling Speed
Thanks for the feedback everyone, I do have a MSD on the engine and will see how far I can idle her down tomorrow.
We'll be trolling most of the day so I'll have some time.
Thannks again!
Mike
Date: 08:23 a.m. on 04-13-2001
Pottsie
6. Re:20' Open Trolling Speed
I've always had the same problem down here in S.Fla. Flat days sometime result in no current. You want to cover some ground, but don't want to drown your live baits. The answer is: Go spend 30 bucks on a sea anchor and spin the engine at a normal idle. Sure, your engine has to work a little harder, but you will find that you have much better control than trying to maintain a heading at 400 rpm.
Date: 12:07 p.m. on 04-25-2001
Bill
7. Re:20' Open Trolling Speed
I drag a 5 gallon spackle bucket with a rope behind my 20" WA. Slows her down to 3 knots but I wonder if that giant teaser scares the fish!
Date: 07:11 p.m. on 04-25-2001