Anyone running a TLDI? Need help?

[Coontakinta]

Im interested in hearing from anyone who is running a 90hp TLDI and on what hull they have it on. the reason being that I have one on the back of my 5m Seaquest Eclipse and am VERY disapointed with its performance. :(

The hull is a plate alloy of some 435kg add approx 125 litres of fuel and the weight of three adults plus the 143kg for the donk and all I can get out of the rig spinning the standard 15" blade is 56km/h @ 5000 WOT.

At the insistance of the dealer I tried a S/S 14" yamaha prop and managed to spin this fiqure out to 5600 rpm @WOT with a top speed of only 53km/h.

Speaking with Solas, they suggest raising the motor and fitting a S/S 15" cupped blade. Thing is I 8nt sure I have any adjustment left in the height.

How do these figures compare with other TLDI users?

[Coontakinta]

Here is another pic of the set up.

I ve heard from solas that they have had similar complaints about poor performance from TLDI's. can anyone confirm this? :-/

[joey_1987]

Hey, here's a review of the engine in question: http://boatpoint.ninemsn.com.au/portal/alias__boatpointau/tabID__200859/ArticleID__117643/DesktopDefault.aspx
It says 58.9km/h at 5600rpm and its on a haines signature 520c pushing a total of 920kg so not a small boat either. Hope this helps. Joey.

[nevd]

I have replied to your post on another site on a related prop performance issue. I hope this helped.

To check the height more accurately, please trim the motor so the AV plate is parallel to the keel and then place a straight edge along the keel and under the AV plate. Then measure the dimension from the bottom of the AV plate to the top edge of the straight edge. With a good stainless prop, you should be able to run AV plate 30 to 40 above hull keel and increased cupping will allow motor to run even higher. Another check is the AV plate should be just above the water at high speed and the motor should be trimmed so the AV plate is parallel to the water. If you can trim up more than the AV plate parallel to the water and not have the prop blow out, then you can lift the motor higher. If the AV plate is more than 30 above the water at high speeds, then you need to check cooling water pressure.

Your photos indicate (but it is not very clear) that you are already over 20 above keel so you may not be able to lift more than 1 hole and I doubt lifting 1 hole will increase revs more than 300.

It is risky for the motor to be propped so it only does 5000 at WOT - ideal is 5700 to 5900. Before you spend more money on alternative props, I recommend you discuss your motor performance problems with Neptune Marine in Brisbane.

Please let us know how you go.

[88fishframe]

The tohatsu's are not necesarily a big block for a 90 and I think torque is not overly great for your boat which will be pushing 850kg's fully loaded.

My 5m plate boat runs a 130hp which will give it 76kph - the previous 90hp I had ran out of puff at 50kph.

The rpm figures you quote seem fine to me and I don't think you will be able to get much more out of it.

David.

[saurian]

Coony, know seaquests better than tldis.
Seaquest only have moderate deadrise compared to haines in comparison test. Note haines 5.2 is probably in overall length only .
Sea quest is probably 5.6m+ overall ???? So boat test is comparing different apples. I have had larger w.a. platey with 90 hp 4 st, it maxed out at 53 km/hr at 5600 rpm. I tryed few props until i settled for solas
which did 48 km/hr but used 20 % less fuel.
If you are really after speed i do not think the brand/ more the hp size is the answer. Although i have been wrong before. See if other people with
seaquest boats get better figures with other brand 2 strokers.
Best of luck , nice boat....

[Coontakinta]

@ nevd.....Thanx for the advice and the PM will get back to u on that question soon. ;) Have checked the cav plate height when under load only yesterday and it would seem that I could get the motor up a coupla holes as it was about an inch under @ WOT. Also noted that the 14" blade was spinning & 5800 / 5850rpm . Amazing the difference the glassy sea made in this :-[ 5850 is max rpm for this motor so I'm reluctant to spin it out any further. Is Neptune Marine a Tohatsu and Seaquest dealer?

@ David.......Geez m8 which 5m plate did u have that allowed a 130 on the back? As 4 the tohie not being a big block.............. yeh ur right! In my mind I screwed up in not doing my homework properly and the torque in the tldi does not seem as high as that from say the e-tec. :'(

90 e-tec 89.8hp @5500rpm
90 optimax 89.8hp @5375rpm
90 tldi 88.7hp @5500rpm :'(

Thanx for the help guys will keep u posted on progress ;)

[88fishframe]

Hi Coontakinta.

The plate alloy I was using at the time was a Cairns Custom Craft - no worries with up to 150hp, but it was a pretty solid boat !

;D

[nevd]

Neptune are very long term Tohatsu dealers with probably the most TLDI experience in Australia.

Glad to hear you were able to get the revs up.

Where did you get all the power figures, was it the US EPA Certification site?

[Coontakinta]

Nah, nevd, all the rpm fiqures came from a boatpoint.com review on various 4 stroke v 2 stroke DI's.

With Neptune being so atune to the TLDI, will send them an e-mail and see what i can get from them. Should I be quoting any names nevd?