Venture 34 DF300AP repower tread

[ChrigelKarrer]

My recently aquired 2009 Venture 34 with full tower and buggy top had twin Yamaha F250 with 2000 hours.
As this is a charterboat for offshore fishing andd scuba diving i decided to sell the F250 and get DF300AP to stay relaxed for the next years regarding upcoming engine problems with the 2000 hours F250.

As i have already one 2013 DF300AP i know this engine and i am happy with it and the considerable lower price for the Suzuki was a no brainer go with Suzuki.

Friday 22nd of April from 9 am to 3 pm we took off the F250 including all harnesses, controls, gauges, etc and the buyer came to pick them up.
The 2 cages with the DF300AP where delivered at 3.30 pm so we where able to mount the engines on the stern and isntall some of the gauges and NMEA bus devices.

Saturday 23rd of April 8 am to 4 pm we could sucessfully install all the cabeling, controls and gauges for lower and upper station and fire up the engines using the flush port, a half an hour the forklift droped her in the sea and we could do a quick spin to check everything.
Results where that all is working fine, just the original propellers where ventilating.

From then on i did several trips to break in the engines and have actually 12 hours done.

Here some important data:
Mounting height: 2 hole up (same as Yamaha)
Propellers: LH and RH Mercury Mirage Pro 18''
Counterrotation: is as "standard" on port side

First i wan't to send big KUDO's to Outboard Specialities, they did a perfect job programming the engines, setting up all connections and deliver them to Miami where my freight forwarder shipped them to Costa Rica.
I got the engines perfectly Plug and Play, all programmed and in working order so that we just had to hang the engines, install the gauges and controls and pull the cables.

The engines are working fine and as expected and installation was flawless and we could do it in about a day, 4 people working on that.

There are three problems to solve:

1° Engine height
this is a heavily discussed argument, i installed the engines same height and using the same propellers as the F250 setup to see if that works.
Unfortunately the propellers ventilate always, depending on the load more or less.
2 people, short period swell ventilation is bad
2 people, almost flat conditions ventilation is almost absent
7 people, 3 ft chop, 6 in bow, ventilation is bad
7 people, 3-5 ft chop, 3 in bow and 3 on the stern, ventilation is very bad

There is one Venture 34 with DF300AP mounted on the highest position and it seems it goes well on the ICW and 1 person aboard, but i am waiting to get his results in the open sea.

Now don't know what to do, to lift the engines up to see if they work better as the AV plate is burried and not visible in the water or drop the engines all down what probably helps but will be too low.

Unfortunately to change the engine height will cost me about 500$ for lift, space rent in the local marina, so i would like to be sure what to do.

2° Propellers
I think that the before used Mirage pro 18'' is too small as the Suzuki has different LU gear ratio and 50HP per engine more, so i believe that the DF300AP could swing at 19'' or 20'' propeller.
I have a friend ho borrows me a Powertech OWL 17 four blade propellers,
so i will test them as soon i get the hub assembly or Suzuki.


3° Software problems
I choosed to have SMIS gauhges as it seems that the new Suzuki gauges have issues with fogging and as the boat is in Costa Rica this would be most likely a issue here.
From the beginning the gauges show error codes, "check engine" pop-up's and unmotivated "Forward" pop-ups with very annoying beeps.
Dealer say that this is a issue with 2016 DF300AP engines and the SMIS gauges and that Suzuki is working on that.
Well then, i will switch off the alarm beeps to avoid to scare me and the clients and i'm crossing fingers that Suzuki solve this issue soon.

Thoughts:

I work part time in a shipyard where we sell Suzuki engines and the problem with engine height was always a issue.
I personally assisted the install of 4 DF300AP on 3 boats,
1 28 ft RIB for watertaxi use with single engine
1 28 ft RIB for dive operation (mine) with single engine
1 34 ft Venture 34 with twin engines

All 3 of this boats had the same problem with ventilation and all 3 of those boats have a euro transom with a step about 3 ft before the transom.
Watching the attached picture of my Venture 34 i notice a very foamy waterflow around the lower units and this let me believe that the problem is there.
I start to think that hulls with a step before the transom create a different waterflow than a straight transom, and this may be the culprit of the Suzuki LU ventilation problem.
I think that a sternheavy boat create a steeper upwards angle so that the upstreaming water can touch the diagonal upward going transom and create a vortex introducing air in the waterflow.
This would also explain why the ventilation become much less or disapear when i have a lot of weight on the bow and it worsens when i have more weight on the stern (when the propellers run deeper)

We could solve the ventilation problem (against all odds) on the 28ft watertaxi mounting the engines higher than before, hard to belive, but so it was ...

Chris

[Moonlighter]

Hi Chris and welcome to the forum!

Outboard Specialties are a well regarded Suzuki dealership from what i have seen on forums such as THT. They do know their Suzuki's very well.

Regarding the issue with alarms, every new engine year can bring up issues. However, the first thing to check is that the engine interface software and the SMIS software are compatible versions.

This is what Suzuki says SHOULD work with your engines:

1. Interface sw version 3.5.0 (make sure both engine interface cables are running this version). Unfortunately you cant check this on the SMIS gauges, you need a Lowrance or Simrad MDF on the network to be able to check.

2. SMIS sw version 2.7, you can check this on each SMIS gauge to see what they show.

Again, if you have a Lowrance or Simrad MFD on your network it is quite simple to update the sw on the interfaces and SMIS displays. Let me know if you have, and I can send you links to the SW files that you can copy to a sd card.

It is of course possible that the latest 2016 engines might have changed again, but the above should be checked and tested first to make sure that everything is as per recommended.

Regarding the propellors, it is very unlikely that the exact same props from the Yamahas will work with the Suzukis, as you have discovered, due to the vastly different gear ratios.

The 300's would normally run a 16" diameter prop and probably something like a 23" pitch. Outboard Specialties should be able to advise you about suitable props they have used on these engines on similar boats. And also they should be able to help with height.

Good luck, it looks like a great boat setup you have there! Some persistence will get these teething problems sorted out.

[ChrigelKarrer]

Hi Moonlighter,
thanks for your reply!

Yes Outboard Specialities did a great job preparing the engines for me, ship them, supporting me with this problem and yes, they advised me regarding the propeller and the engine height.
They just finished a repower of a identical Venture 34 with identical engines and they could run flawless on the ICW with the engines mounted 3 holes higher (all up ).
As i am fishing and cruisimg the pacific i need that the engines have excellent grip in 10-15 ft long period swells and sometimes nasty 3-5ft short period chop.

I am waiting the owners of the recently repowered (and identical) Venture 34 run well with the engines all up or if the owner has issues when the sea get rough.
After my experiences with repowering with Suzuki DF200 and DF300AP i belived that Suzukis need to run deeper than the rest of the pack,
meanwhile i start to believe that this issue depend on the type of transom.
This would explain why certain people have the problem that Suzukis ventilate at the same depth as the well running engine before and others don't have this problem.
I had this problems on 2 boats with a stepped transom and on my Panga who has a curved (semi tunnel like) delta pad and on both other boats the Suzukis needed to be lowered 2 holes to work ok (and far from beeing perfect).
It would be interesting to repower my twin F150 BW 23 Outrage with twin DF150 to see what will happen as the Outrage 23 has a straight transom and the trim angle is very broad, much broader than my other boats with the Suzuki's where i need to run them almost tucked in to not ventilate.
On the Panga it is not a propeller problem as i run the Suzuki 16'' 3 blade propeller and still the engine trim need to be tucked in or max vertical, if higher i can hear the blades splashing while ideling and going faster it ventilate and loose grip.

As i live far from a Suzuki dealership i bought the shop manual and SDS software/cables and i hope that i can either:
a) check the software version of the lowrance Suzuki Engine Interface
b) upload a new software as soon the software becomes available

I was aware that the original propellers won't work well, it was just a try to see how they behave and get some data for choosing the final propeller size.

As i want to go once more with 4 blade propellers for manouverability, lower planning speed and better mid range fuel consumption i probably will go with 18-20 ich powertech or mercury propellers. Fortunately i have a friend selling his 17'' 4 blade powertech props, so as soon i have the Suzuki hub for them i will try them to see how they behave.
I wish i would live in the Miami area to be able to rent them from propGods till i found the right one.
I verified also the propeller slip with the Mirage Pro 18 and the result is a shocking 35-50% slip, before with the F250, now with the Suzukis and the performance data i could find in Internet.
Very surprising is that the ventilating Suzukis have about 10-15% less slip than the non ventilating F250 Yamahas with the same propellers.

The Venture 34 is a very heavy boat and need a lot of power to bring her to plane at 29 mph at 4000rpm with the F250 and actually 22 mph at 4400 rpm with the DF300AP.

Thanks so much for your help!

Chris

[Moonlighter]

Hi again Chris

Since you have the SDS software and cables to connect, you can try to check the engine interface software versions. Also you could check with Outboard Specialties to ask them what versions they loaded before they were shipped to you.

Yes, a good idea to find out how the identical boat and new motors performs, and what propellors he is using - he can do testing and you can copy his results!

Also, Suzuki stailess propellors have a reputation for under-stating their actual pitch - so that a Suzuki 23" prop, when accurately measured, is more like 24" or even more. So thus explains the impossibly low slip figures that you get feom the calculations. It makes selecting different manufacturer proellors more difficult because you cannot compare them with Suzuki with any certainty.

Good luck, and let us know how you go.