370 Venture planing issues

RHKIII

New Member
Jan 22, 2023
18
Great South Bay, Long Island South Shore
Boat Info
2014 37 Venture w/ twin 300 Mercury Verado outboards
Engines
300 Mercury Verado
Greeting all. New forum member. Saw some prior posts about alternate prop geometry. We had a custom prop house sell us 16D x 15P Enigma knockoffs this past season. RMP lowered to 5600 at wide open vs. 6300 with original props. Still takes about 20 seconds to plane off with moderate load. but cruses at 25mph at about 4700 rpm. Have not tried it fully loaded yet. Has anyone tried adding hydra-foils to the lower units to increase lift while planing? Would appreciate any feedback from the forum on how to deal with getting out of the hole with a full load. Thanks!
 
What whould you recommend then? Trying to find a balance between getting on plane and not over reving at WOT.

Do you know the recommended max RPM for these Verados? With my original props I was topping out at 6400, which to me is way too high. Had way to many mechanical repair issues.
 
Welcome aboard CSR. Love the 370 Venture. There have been tons of post/threads on here over the years about their performance woe's, be it prop's or engine HP. I would be very surprised if the people over at https://www.sharrowmarine.com/ wouldn't be extremely interested in assisting you and other 370V owners rectifying your concerns.
 
What whould you recommend then? Trying to find a balance between getting on plane and not over reving at WOT.

Do you know the recommended max RPM for these Verados? With my original props I was topping out at 6400, which to me is way too high. Had way too many mechanical repair issues.
5800-6400 max rpm. You want to be closer to the top.
 
If you want more stern lift you are running the wrong props. Large blade high rake 3 blade props are bow lifting. You would want a Merc Rev4 or maybe a Powertech Ofs4 for more stern lift.
 
Let those Verados run. It's not what "you feel" is right or wrong. As noted above, you WANT to be able to reach the upper range of the RPM band. That is a GOOD thing. If you're really pushing the boat on a calm day with a light load and you're starting to over-rev, well, you can control that.

Foils? Sure, they've been around for a long time. It's hit or miss as to whether or not they help a particular setup... sometimes they make things worse. I wouldn't do it.

You didn't mention if you're trimming properly for your hole shot. Trim the engines ALL they way down EVERYTIME and also use your tabs - you can depoly them ALL the way, as well.

As it stands right now, those custom props you had done are wrong for your setup. You're actually hurting the engine by using them... and making the hole shot worse.
 
Thanks for all the feedback people. Regarding trim at hole shot, motors are trimmed al later way down, tabs all the way down, every time.

The props that were on the boat when we purchased it were 15.3 x 14 Enertia. The boat did plane under full load but I did not like cruising at 5,500 rpm to keep the boat running true. I am considering having them cupped this winter to lower the WOT rpm and add some additional efficiency. Thoughts on this approach?

Also, does anyone have experience running the 4 bladed PowerTech OFS wheels mentioned above? Curious on what pitch would be the best choice.
 
If you want more stern lift you are running the wrong props. Large blade high rake 3 blade props are bow lifting. You would want a Merc Rev4 or maybe a Powertech Ofs4 for more stern lift.

Thanks for the input. I'm guessing on the OFS4 the pitch would be 13 at most? Do you know anyone running these props? When I re-propped last season my custom guy told me that I couldn't get 4 blade props with a low enough pitch. Guess he was wrong. There are so many options it's hard to know how to solve the problem.
 
Let those Verados run. It's not what "you feel" is right or wrong. As noted above, you WANT to be able to reach the upper range of the RPM band. That is a GOOD thing. If you're really pushing the boat on a calm day with a light load and you're starting to over-rev, well, you can control that.

Foils? Sure, they've been around for a long time. It's hit or miss as to whether or not they help a particular setup... sometimes they make things worse. I wouldn't do it.

You didn't mention if you're trimming properly for your hole shot. Trim the engines ALL they way down EVERYTIME and also use your tabs - you can depoly them ALL the way, as well.

As it stands right now, those custom props you had done are wrong for your setup. You're actually hurting the engine by using them... and making the hole shot worse.


Thanks for the thoughts. I wanted to go to a 4 blade prop for the extra lift and mid range performance last season. My guy told me I couldn't get low enough pitch but I see the PowerTech wheels go down to 12". I ended up with a PowerTech16 x 15. I'm really struggling with what is the right way to solve this performance issue.
 
If by "running true" you mean a leisurely cruising speed, I suppose that 5,500 does sound high. It would help to add what the actual speed is. According to Sea Ray, those Enertia's are the standard props and should give you a top end speed of somewhere in the low 40-mph range.

With the Enertia's, what is your max speed and max RPM at that speed? If you can't get the spec'd speed at near the upper range of the RPM spec, then there might be other issues - whether mechanical or possibly a dirty hull.

Also... did you see Post #10?
 
If by "running true" you mean a leisurely cruising speed, I suppose that 5,500 does sound high. It would help to add what the actual speed is. According to Sea Ray, those Enertia's are the standard props and should give you a top end speed of somewhere in the low 40-mph range.

With the Enertia's, what is your max speed and max RPM at that speed? If you can't get the spec'd speed at near the upper range of the RPM spec, then there might be other issues - whether mechanical or possibly a dirty hull.

Also... did you see Post #10?

Yes, so running true would mean a comfortable cruising speed (25-27mph) at a comfortable RPM. With the original 15.3 x 14 wheels, I had to turn 5,200-5,300 to keep the boat on plane at 25MPH, burning close to 35 GPH. Below that speed, the boat starts to squat and fall off plane using auto mode on trim tabs. Is that common to the Venture?? At WOT we were turning 6,300-6,400 RPM and toping out in the low 40's.

With the current wheels 16 x 15 I'm doing 25 at about 4,800 RPM and getting to mid-40's at about 5,800 RPM. Problem is, it could take 20-30 seconds to plane off with about 3/4 full and 2-4 adults on board.

I did look at post#10 and am not seeing that kind of performance with my boat. Would love to cruise at 25 mph at 4,400 rpm! I did not see anything about prop geometry in the feed, unless I missed it.

I suppose it's possible the hull was dirty, but no barnacles, if that's what you were thinking. It seems I'm constantly replacing the cylinder coils but I will not run the boat when a coil dies until it gets replaced.

My thought is to add a cup to the props that were on the boat when we purchased it(15.3 x 14), or press my prop guy for a set of 4 blazers, not sure what the pitch should be.

Thanks!!
 
When did you obtain the boat? Did you purchase it new and if so what was it's performance then or what did the survey note on the performance?
Secondly, on the engine's vs propellers - the engine's must be able to turn their rated RPM's so the propellers must be sized to that specification. With that said there is a host of configurations that will allow the engines to perform to spec yet make the boat behave differently such as aft lift during acceleration and cruise.
Lastly, over 40 MPH in a 37 foot cruiser is respectable with 600 HP in outboards - that boat is a bit aft heavy after all. I would also be concerned with the cruise performance and being on the hairy edge on planning at 25 MPH with tabs all the way down and engines trimmed in. With these numbers so far off the mark, I don't think any lifting device will correct the situation. Have you weighed the boat?
 
Yes, so running true would mean a comfortable cruising speed (25-27mph) at a comfortable RPM. With the original 15.3 x 14 wheels, I had to turn 5,200-5,300 to keep the boat on plane at 25MPH, burning close to 35 GPH. Below that speed, the boat starts to squat and fall off plane using auto mode on trim tabs. Is that common to the Venture?? At WOT we were turning 6,300-6,400 RPM and toping out in the low 40's.

With the current wheels 16 x 15 I'm doing 25 at about 4,800 RPM and getting to mid-40's at about 5,800 RPM. Problem is, it could take 20-30 seconds to plane off with about 3/4 full and 2-4 adults on board.

I did look at post#10 and am not seeing that kind of performance with my boat. Would love to cruise at 25 mph at 4,400 rpm! I did not see anything about prop geometry in the feed, unless I missed it.

I suppose it's possible the hull was dirty, but no barnacles, if that's what you were thinking. It seems I'm constantly replacing the cylinder coils but I will not run the boat when a coil dies until it gets replaced.

My thought is to add a cup to the props that were on the boat when we purchased it(15.3 x 14), or press my prop guy for a set of 4 blazers, not sure what the pitch should be.

Thanks!!
As evidenced by the numbers, you are overpropped as we suggested earlier. Read the dedicated Venture thread, the prop issue was discussed there. And don’t think of those outboards like stern drives or inboards, they are going to turn higher rpm to cruise. Typically 4000 rpm is cruise rpm on a Verado, even higher, and that is perfectly fine.
 
I suppose it's possible the hull was dirty, but no barnacles, if that's what you were thinking. It seems I'm constantly replacing the cylinder coils but I will not run the boat when a coil dies until it gets replaced.
Yes, that was what I was thinking - slime, not barnacles. Especially if the boat sat for a while before you purchased it. I think it would be good to make sure the bottom is perfectly clean before doing anything else. Just a LIGHT slime layer will have a big effect on performance and could easily explain your issues. There could still be another reason... but a dirty bottom is definitely in the realm of possibilities here and if that's not taken care of first, then everything else is a waste of time.
 
OP - this issue was discussed and resolved, I posted a link to the thread. Dont over think it...get the props that we all got and you will be happy. Several owners have and each one has been thrilled. You will lose a few MPH at top end but you will jump on plane and remain there at a perfect cruising speed.
 
With a full load of fuel, water, and people I dont need any trim tabs and I jump up on plane easily. We cruise around 30mph at about 5200 rpms and burn about 32-35 gph. This is faster and less fuel efficient than what we could do, I jsut like that speed. You could easily be at 4700-5000 rpms, 25mph, and sub 30 gph. WOT is 6400 rpms and about 38mph. Believe me...just do it.
 

Forum statistics

Threads
112,950
Messages
1,422,861
Members
60,932
Latest member
juliediane
Back
Top