Phantom 18ft 175hp V6 Mariner

[fullbore]

Can only get 5k rev`s trim in,with lazer2 21p.
Need more, any idea`s?

[The Docta]

smaller pitch prop will give you more revs - but if its a v6 175 spinning a 21 laser id have thought you'd be getting more than 5k anyway. Sure the gauge is reading right?

What speed u getting??

[fullbore]

Originally Posted by The Docta

smaller pitch prop will give you more revs - but if its a v6 175 spinning a 21 laser id have thought you'd be getting more than 5k anyway. Sure the gauge is reading right?

What speed u getting??

No reason to think Gauge is wrong,but not sure.
52mph from speedo of gearbox,what about lifting engine up a bolt?

[The Docta]

Low 50's does sound a little slow for your set up. Id have thought you'd see mid to high 50's at least.

Could try jacking it up a bolt. How far under the bottom of the hull does the centre of the gearbox case sit at the moment?

Risk with jacking up the motor is that you run it too high and end up with low water pressure. Do you have standard pickups or low water pickups? If they are standard, you can block the top two sets off which may allow you to run a little higher.

I forget how far under the bottom of the hull the bullet should be but am sure someone else can advise

Best of luck

[fullbore]

Originally Posted by The Docta

Low 50's does sound a little slow for your set up. Id have thought you'd see mid to high 50's at least.

Could try jacking it up a bolt. How far under the bottom of the hull does the centre of the gearbox case sit at the moment?

Risk with jacking up the motor is that you run it too high and end up with low water pressure. Do you have standard pickups or low water pickups? If they are standard, you can block the top two sets off which may allow you to run a little higher.

I forget how far under the bottom of the hull the bullet should be but am sure someone else can advise

Best of luck

Cheers for advise will let you no outcome

[Burty]

I'd have thought 5000rpm was about right as trimming out should pick up 1000revs and at 5 to 8mph

[dave_123]

when fitting an outboard the cavertashion plate should be flush with the bottom of the boat take a straght peace of wood and hold it on the bottom of the cav plate and jack engine up untill the wood is on the bottom of the boat if u see what i mean sorry about the spelling like the post before mine 5000 is about as much as u want to rev if its a mercury/mariner they only rev to 5500 and some to 6000
depending if its the optimax or the 4stroke range..if u go down an inch on the prop u might find that u are on the edge of the rev limmiter and the smallest amount of trim out and u will have beeps goin off every 2 minutes

[sinkunit0]

don,t know about a 175 but a bog standard 200 with a low water pick runs about 70 best was 73. a good starting point was propstaft about 1" below bottom of boat. i would get a laser 23. the engine should also be making more rpm. if in doubt trim out

[fullbore]

Originally Posted by fullbore

No reason to think Gauge is wrong,but not sure.
52mph from speedo of gearbox,what about lifting engine up a bolt?

I`ve just changed to a foot throttle after 10 yrs since had boat,i know i`ve missed out on proper control of boat all these yrs ,anyway i`ve taken throttle cable off from control box when i realised the cable was not located properly in box so when full throttle applied all of the cable was moving forward so im 99% sure this is why only 5k rev`s.Yet to try as still on refit of interior.watch this space.

[Wayne Kerr]

Originally Posted by dave_123

when fitting an outboard the cavertashion plate should be flush with the bottom of the boat

Really ,,, now we know what the problem is.
We've all got it wrong from day one, maybe that's why our fishing gear goes over the back when we put our foot down!


Thanks Grave_ 321.

[Cookee]

Originally Posted by dave_123

when fitting an outboard the cavitaion plate should be flush with the bottom of the boat take a straight peace of wood and hold it on the bottom of the cavitation plate and jack engine up until the wood is on the bottom of the boat if you see what i mean sorry about the spelling like the post before mine 5000 is about as much as u want to rev if its a mercury/mariner they only rev to 5500 and some to 6000
depending if its the Optimax or the 4stroke range..if u go down an inch on the prop u might find that you are on the edge of the rev limiter and the smallest amount of trim out and you will have beeps going off every 2 minutes

Just out of interest how long have you been a marine technician?

[Matt]

I know what you're thinking.

[Tony Davis]

[Burty]

I went in a boat once with the engine fitted as described above i only got about 200yards before turning round and giving it back to the owner as i didn't like the fact that my head was in the water because the boat rolled over so much

[fullbore]

Got to be in it to win it!

[fullbore]

Originally Posted by The Docta

Low 50's does sound a little slow for your set up. Id have thought you'd see mid to high 50's at least.

Could try jacking it up a bolt. How far under the bottom of the hull does the centre of the gearbox case sit at the moment?

Risk with jacking up the motor is that you run it too high and end up with low water pressure. Do you have standard pickups or low water pickups? If they are standard, you can block the top two sets off which may allow you to run a little higher.

I forget how far under the bottom of the hull the bullet should be but am sure someone else can advise

Best of luck

Sorted.Control box throttle cable not attached properly,so not getting full chat.now pullin full rev`s.Nice