Pretty easy to ascertain what cylinders are being discussed here, and since one brand uses a Stainless tiller arm, the other an aluminum plate, I'd say the statements are pretty fair in general.
Pretty easy to ascertain what cylinders are being discussed here, and since one brand uses a Stainless tiller arm, the other an aluminum plate, I'd say the statements are pretty fair in general.
Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
Still consider myself a "Marine Apprentice" after 47 years (learn something new every day).
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It has taken a while, but the dealer invited me to go on the maiden voyage with the new motor Saturday. We didn't do much with it, but it is very quiet compared to the old 175 efi. It still needs a couple of minor things and I will get it on Tuesday and begin the break in process. We are starting with a 23p Fury. The 19 year old boat looks like a new one with that motor. This is my first shot at posting a picture so I hope it works.
Very nice, quite an upgrade/update!! Enjoy
Probably a dumb question, but did you have to replace controls?
I did not have to replace the gear shift control, but I replaced the key switch because I wanted a mercmonitor and I think the new key switch was part of the smartcraft cabling or something like that.Originally Posted by MikeKz
I have over 3 hours on the motor now and I have installed a Mercmonitor that I purchased from European Marine along with the water pressure sensor. According to the Mercmonitor my peak speed was 61.3 at 5350 RPMs. It is at 2 1/2 inches PTP and as previously stated it has a 23p fury. I had a half tank of gas (it holds 35 gallons), empty livewells, and most of my tackle. Bumblebees are known for requiring driver input and i am good with that, but It is chine walking earlier than it used to with the old motor and it feels like it is lifting out of the water earlier. I dont think it used to start walking until 62 or 63mph. The old 175 efi 2 stroke would run mid 60s at 5800 with a 25 tempest. Dry hull weight is 1050 lbs. Do I need a different prop or raise the motor? The new hydraulic steering is taking some getting used to as well.
Last edited by hydroplane; 08-26-2019 at 07:11 PM. Reason: Edited to change PTP to 2 1/2 from 3 1/2.
Yes probably too much prop and motor is too low. I found with these new motors/lower units they are much more efficient and a lot less prop slip. What is your water pressure at WOT?
It would be nice if the Mercmonitor showed what the PSI was at peak speed. I know I remember seeing 19 and 20, but to be honest I m not sure what it was at peak. I had a handful at peak speed and didn't look down. I will pay better attention next time. I just calculated the prop slip on mercury's web site and it said 3. Is that possible or is something wrong with the numbers on the monitor?
I am running a 200 4s and a 23 tempest plus at 5800 rpm and 69.5 mph. Mercury’s slip calculator says 4% for that so I don’t think 3% is unrealistic. I would expect that number to go up a bit as RPMs increase. I would raise your motor in 1/2” increments and see how it performs and watch H20 pressure.
Thanks for your replies. I have never had to worry about the setup, I bought the boat from Jacos and back in the day they were the Bumblebee kings and had it setup perfect. I will have to learn how to adjust a jackplate now. What water pressure should I be aiming for?
18-20psi minimum at 100% wide open. Yeah a lot of us relearning going from 2s to 4s, usually having to drop a pitch or two from the 2s setup.
I re-measured tonight and got the same measurements, but I did some bad math last night. 13 - 10.5 is 2.5 not 3.5 so I'm at 2 1/2 PTP not 3.5. Does this change anything?
I would go up 1/2” and see what happens with water pressure and see if chine is easier to handle. Also see how the prop spins on hole shot, you may need to change PVS plugs. Also with only 3 hours on motor maybe some more seat time before making changes.
Update: I was having issues getting my prop to pad measurements correct. I couldnt measure the same thing twice. I have figured out what I was doing wrong plus my garage floor is not as level as it looks. Now I can re-create the measurements and they match up with how much I have raised the motor. I actually started at 4 1/8".
4 1/8" - 61.3@5350 RPM 21 PSI
3 1/2" - 61.4@5350 RPM 21 PSI (Chine walk got way easier to handle and everything felt good again)
3 1/4" - 60.3@5230 RPM 21 PSI (Added 8 Gallons of Gas(might explain 1mph drop?), no noticable change in handling)
3" ???
Is it strange that I have raised the motor almost an inch and there has been no noticable change in anything? Would this be an indication that I am not getting 100% throttle? I have contacted the dealer today and asked if they even checked it and I didnt get a good answer just that I could bring it down and they would check it. I have it set to 3" now, but havent driven it yet. I think I need to verify that I am getting 100% throttle before I continue. Any thoughts?
Think you are on the right path but still maybe too much prop.
I think Dave is on the right track in this thoughts.
The 175 ProXS has a WOT range of 5400-6000 rpm. Maybe try dropping in pitch and get the rpm's up closer to 6000
Thanks guys. I may go ahead and run it tonight at 3" just to see if there is a change yet. I have an appointment at the dealer Friday. If I'm getting 100% on throttle I will try the 22. I was running a tempest before, but I have read how much Bees like the Fury and the dealer thought that would be best as well. I notice you like the tempest for this boat. Is it just because they like to ride higher? I have zero knowledge on props and I don't have a lot of confidence in the dealer right now.
The fury is probably better for lighter hulls like your Bee but they don’t make it in a small enough pitch for you to be in the optimum RPM range. You may talk to Mark Croxton about having it worked or one of his Razor props.
Keep us updated!
Went to the dealer and my throttle was at 88%. It's at 100% now. Before I drove it I put it back to 3.5 PTP so I could compare apples to apples. it drove awesome like my old motor. I got 66.0 MPH @ 5650 RPM and had 24psi water pressure. I gained almost 5mph. Knowing i still need 200 more RPM, I pulled it out and raised it 1/4" and drove it again. I got 65.1@ 5360rpm and had 23psi. I lost speed and RPM. Should that happen? Should I raise it again by 1/4' and see what happens since I have plenty of water pressure? I didn't have time to change it and run it again today. Also the air temp was 95. When it gets colder will I gain the other 150-200 RPM? If I had 5800 RPM @ 3.5" I would be totally happy, it drove that well and my goal was 65 loaded and I got 66.
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