Top speed of a Outerbanks?

I have been out 2 times on the 30 ft. Outerbanks (KIK-N-BAK). I am very pleased on the way it handles. I do not think I would ever go with a single drive again. I was a Tuna Fisherman in my youth and operated a big skiff with a 671 Jimmy, single rudder. Was very good at steering the wide beast. My boat has twin TAMD 41 diesels and spins on a dime. Each are 210 hp. I ran all day at about 1200 rpms and burned about 10 to 12 gallons. Average from 5 to 6 knots according to the gps. The waters were sort of choppy but I am used to it. Once I got my sea legs going I decided to push it and see how it handled the high swell and confused seas. It did better at 2000 rpms and about 10 knots. It plowed through the water. When I was going slower, I took a few over the bow but felt very comfortable. The engines run about 160 deg at 1200 rpms. Pick up the speed to 2000 rpms and the temp goes to about 180 deg, which is probably where the stats are wide open. I do not want to push the engines until I feel more comfortable with the engines. Looking at what the boat does at 1200 and 2000, I figure I might be able to get about 13 knots max. I wieghed the boat and trailer, 3 axle, scales showed 21000 lbs. for all 3. The truck is about 6900, not sure about the 3 axle trailer, maybe 1500 lbs. I am guessing the boat is about 12,500 to 13,000, me and friend 500 lb and misc gear, about 14000 total. Maybe more. I read the specs on the engines and they are made for easy repair, maintenance, and fuel economy. I agree on all 3 points. Does anybody have any ideas on what speed I should get from all this info. If the props were tweeked , could I get a few more knots.
The boat was built for commercial fishing and can hold about 4000 lbs of fish, so the props may have been spec'd to get power rather then speed. Even if I do not get more then 12 knots, I am very happy with the boat. It lays over and comes back to center, pitches and yauls and all that and returns back to center. I did not feel it go much past center after each roll. When going into the swell it pops back up, you can feel it drop into the swell and the feel the bow pick up fast. Going down swell it comes back on course by itself. I left the boat alone going down swell to see if it came back to course and it settled down ok. It responds slow to the turn , whcih could cause someone to over steer the boat. I am sure it might act differnet according to a different swell size. I am learning how the boats acts and so far I can not be more pleased. Again, the best is when manuevering in tight corners at the ramp. I will send some picks as soon as I can get my daughters camera to only show boat picks and not all the other pictures she took of other things.
Al

Hi Al,

Sounds like you are getting a good feel for how your new ride handles. Wish I could help you with the info you are requesting but, I have no experience with vessels with that configuration. Seems that you should be able to squeeze a few more knots out of her but, maybe it was just the conditions. Try to get a feel for her in flat seas as well and average it out. Tenacious
(26' Billfisher w/ 200HP) does 20 Knots cruise in flat seas but, when it's rough I can only get maybe 16 knots depending on conditions. Even if you can only cruise at 12 knots it's no big deal. It just means more time on the water which is what we all want, right? This season seems to be shaping up to be one where the fishing will be a little closer. Let's hope we can score fish at the 302 and 371 all summer this year.

Later,

Scott (Tenacious)

Al,

The redline on your engines should be from a low of 3600 to a high of 4000 RPMs; Don used to always tell me Volvo reccommended a cruising RPM of 400-500 RPM less than your maximum RPMs. Now your engines have a few hours on them but I think you should feel comfortable @ a 3000 RPM cruising speed,
just as long as you can get 3500-3600 out of her fully loaded but watch your temp guage as they tend to run hotter at full throttle when you check your max RPMs. What ever RPM you can maintain the 180-190 temp range for an extended period would indicate a max cruising RPM range, if you can't do that at 3200-3400 I would check the raw water impellers and heat exchangers. Remember you have a big, heavy boat and things can go sour in a hurry as far as temps go.

I think you should be able to cruise @ 15 nts at least, let us know how it goes. You're doing it the right way, checking it out slowly and getting used to the boat. Just gain more confidence every trip!

I found a web page that gives spec data on various older volvo engines. Mine is a TAMD 41D, (heavy duty) and rates the engine at the crankshaft to be 145 hp at 2500 rpm. It looks as if the WOT might only be about 3000 rpm. Any body know how to read the specs and understand them to relate to Blackman boat engines? I am starting to believe that they were made getting the heavy boat out of the hole. Next time I take it out, I will put it at full throttle until the temps come up and see if they stop at 190 max. Then I can ck when the engines are off and see if the linkage is full open. Any thoughts are appreciated. Al

http://www.volvo.com/volvopenta/na/e...ngine/inboard/

The TAMD 41D is the same motor as the ADAQ41D, except the TAMD is shaft drive and the ADAQ is I/O; I believe the max RPMs should be the same (3800-4000) for a properly loaded and propped boat. The TAMD has 200 shaft HP and the ADAQ has 185HP measured at the I/O prop shaft, you lose a little going through the I/O gearcase.


I just checked the website, I'm probably wrong! If indeed this is the HD motor, then your 2500max RPM is correct. These numbers just seem like a de-tuned AD41. Maybe it was the TAMBs I was thinking about. I'll do some research and get back.

Al,

From A reliable source I'm told those are the standard 200HP Volvo 41s, not HDs; you should get 3700-3900 rpms @ WOTwith the fish hold empty. The performance on the standards @ 2500 rpms is probably the same as if they were HDs and the previous owners just didn't run them that fast because they were usually loaded full. I would try and see what max you can get from those engines to determine their shape. Running @ 2500 will not tell you anything as far as the current operating condition of the motors.

This is the site where I found the info on the various Volvo engines. I hope this can help others to find out specs on their engines. Al

http://www.volvo.com/volvopenta/na/e...ngine/inboard/

Al,

I just checked with my buddy and he's pretty sure those are standard 200HP 41s, not HDs. You should get 3700-3900 rpms @ WOT with the fish hold empty. Although the performance @ 2500 Rpms is similar to the HDs, the previous owners didn't run that fast as they were full most of the time. You need to wind the motors up to determine their max RPMs and then review the oil pressure and water temp guage positions to come to a conclusion concerning the motors' operating condition and then make repairs and/or modifications to make those RPMs, once they are met you can count on a reliable propulsion system once you decide on a safe, maintainable cruising speed. An exhaust gas pyrometer would be a wise investment and helpful to make sure the engines don't get overloaded.

I want to thank everyone that helped me with looking up info on these engines. It looks like they should be able to run at least from 3000 to 3600 rpms, and not go much over 190 deg. I may take them up to either 200 deg or 3900, which ever comes first and then back down to either 190 deg and or 3600 rpm. I hope they do not fly apart, but if I keep a eye on the gauges , it should give me some warning. I will be close to the engines and have someone else driving so I can feel the exhaust elbow, watch for water leaks, listen for strange sounds and just keep a watch out on everything. I may add the temp for the exhaust gas later, not sure if it should be alarmed or just a digital read out. I will be going out on Saturday and running it about 50 miles out, looking for Blue fin, yellow tails, or maybe a few albies. Thanks again. Al

Al.
Just in case you ever need parts for those 41's, give me a shout. I am the unofficial custodian of the BOCA 41a Boneyard. Everything from heat exchangers, intercoolers, injector pumps, turbos, blah, blah. (No starters or alternators)........rt

Took the boat out yesterday and got up to operating temp of 160 at around 2000 rpm and about 10 to 12 knots.
Pushed up to 3000 rpm- 180 deg & 18 knots and held that rpm.
Continued at 3000 rpm- went to 190 and 20 knots. Stayed there.
Went to 3500 rpm 200 deg and 22 knots.
I did not want to run too long at 200 degrees but everything seemed to be stable at that rpm.
Went for it and pushed up to WOT.
4000 rpms and the temp. needle started moving clockwise real fast. Went to 210 deg and rising to 220 deg and started to smell some paint getting hot, so I backed it down to 2500 and temps went back down in about 3 seconds. That got a little harry. At the higher rpms I noticed a little rummble, or shacking, as if the props might be out of balance. Do brass props or shaft drive get out of balance or is this normal. I ran it about 3000, 190 deg and 20 to 22 knots, and everything seemed to be stable, except for the vibration. I do not want to operate at that unless I want to get somewhere fast. I would only run that spee for not more then 1 hour at a time. Maybe the engines need to run at this rpm to blow out any carbon or junk in the cooling department. I also wonder what the salt water temp is doing. That could give me a good idea of heat transfer. Next time I will have someone else operate the boat and I will be by the engines to see If I can feel the in and out of each heat exchanger. I also can use a infra red heat gun to ck temps. Anybody have comments. It seemed both engines tracked each other exactly, so I do not think they both would have the exact same problem. I could be missing something. Are these temps and speeds about normal for this heavy boat, 15000 lbs? Thanks for the comments. Al

Al

Most of my experience is with the older AQAD40 engines, but I would say you could benefit for a cooler cleaning.

You can hit the designed wide open throttle RPM, so I would think your props are the correct size for the load you are pushing. If you're propped right, you shouldn't have a temperature problem running at full throttle for short periods of time. On my engine I would consider anything over 200 a real problem. (some of you 41 guys chime in here if that engine likes to run hotter)

Back to the cooler cleaning. I came up with a way on the 40 to circulate a mild acid/water solution through the raw water system using a spare pump and a few hoses. The first time I did the flush, I saw a significant drop in running temp, and now consider this to be a 2 year maintenance item.

I you'd like to get together and talk engines some time, give me a call.
I'm just over the hill in Spring Valley.

Mike 465-1617

Mike I'm with you I think it's foolish to run above 190- 200 for any extended length of time because a catastrophy is waiting just around the corner.

Al,

Mike's right, it wouldn't hurt to clean or even send your heat exchangers in for service, but if you stayed @ 3000 or less you could probably hold out until next season if you don't mind keeping a careful eye on the guages. She seems to be propped right and I'll bet your best fuel economy might be at the 16-18 knot range, it's nice to know your boat can attain and maintain that speed easily. Yes the props or shafts might be tweaked slightly to produce the vibration you're experiencing which is common. I think you found a sweet ride!:)

Al,

If you don't already have a couple spare impeller sets onboard you might get some. Once you start runnung above 200 degrees those things start to detereorate fast.

Scott