boat will not plane out!!!

[jaybirdhi]

ok im lost. I have a 1987 baretta 27' with a rebuilt 460. performance distributer, carb, ect... was told it should do about 53mph. here is the problem. when im am crusing at about 5mph everything sounds great. when i give it wot the boat doesnt go any faster. There is no slipping involved. the engive is tuned up great and it is revving good. my tach is broke but it def is getting up there in rpm's. it feels like im pulling a ton of weight and it will not plane out at all. the prop is a 141/2x19 so i think thats good. whatever the problem is seems to get worse and worse every time i use it. i do not have any bottom paint and after just a few weeks in the water i have a ton of barnacles on the bottom. could this be slowing the boat down this much? could it be the trim tabs not working correctly? i have a top speed of 15mph with only 4 people on the boat and the engine is working hard to get there. also a little pinging at wot. should i be using a higher octane? I adjusted the timing so its not to far advanced.

 

[calwldlif]

Re: boat will not plane out!!!

Are you kidding here?<br />If this is real, prop spun.<br />No tach? You keep using it?

 

[Purduebarry]

Re: boat will not plane out!!!

Yes on higher octane , what are you using? I'd recommend at least 91. From what I've read pre-detonation is BAD and you indicated pings. Have you checked the hub of the prop? You may have a spun hub, it would be like a clutch slipping, motor revs high but you don't go anywhere. The barnacles and crud will seriously affect speed and efficiency. Not to 15 mph with a 460 but will hamper top speed etc. I'll let others offer more technical suggestions, timing etc. Post some details...rebuilt when, what kind of outdrive, RPM's at WOT, or what you were told it should be and get the Tach fixed, like driving at night without headlights, risky!

 

[tommays]

Re: boat will not plane out!!!

I allways say

 

[jaybirdhi]

Re: boat will not plane out!!!

thanks for the help, it tach's at about 3200 rps. from there that tach is a little jumpy but its not revving any higher than that. maybe i just need some octance boost. the motor has about40 hours and was rebuild 3 years ago but sat for two years. i have put a new mallory distributer on it as well as a new starter, plugs, and rebuilt the carb. and changed the fuel filter. still feels like im pulling 10 water skiers when i nail the gas.

 

[calwldlif]

Re: boat will not plane out!!!

OK<br />What is different about your boat?<br />Have you changed prop pitch?<br />Did it "work" before sitting 2 years?<br />3200 rpms is way too low,<br />pinging would result, too much and<br />bang no motor.<br />You mentioned barnicals.......

 

[jaybirdhi]

Re: boat will not plane out!!!

i just bought the boat this season so i can only go on what the previous owner told me. i havent changed the pitch but i was told i have the right size. yes there is a ton of barnicals on the bottom. there is no bottom paint the previous owner trailered the boat. i cant see this slowing it down that much. is 3200 rps too low to get it to plane out????

 

[bruceb58]

Re: boat will not plane out!!!

Barnacles will cause a huge difference. Also, if the gas is 2 years old, that gas needs to be removed.

 

[tommays]

Re: boat will not plane out!!!

jaybirdhi <br /><br />I am sure if you ask the other boat owners in your area they will tell you your crazy for not haveing bottom paint<br /><br />You are well on the way to a really long or really costly hull fixing JOB<br /><br />Generaly your in trouble around 5 to 7 days without paint <br /><br />tommays

 

[bomar76]

Re: boat will not plane out!!!

I advise finding a new hobby...

 

[flashback]

Re: boat will not plane out!!!

jaybird, If your engine is a 460 turning 3200 rpm, and If your prop is 14 1/2 x 19, the boat is 27 ft long, and only in the water 2 weeks, Then something has to be slipping...if your only going 15 mph.....what kind of drive is it? actually the engine is not winding up, which tells me that it has a problem. I would think you should get around 25 mph give or take a few at the RPM you stated, although I doubt you will ever see 50..barnacles or no barnacles, I think you have a problem in the drive train. Post a little more info and some of the experts here may be able to figure out whats going on......good luck......

 

[ron7000]

Re: boat will not plane out!!!

Originally posted by jaybirdhi:<br /> i cant see this slowing it down that much. is 3200 rps too low to get it to plane out????

no it's not too low to get the boat to plane but you need to understand the amount of drag on the wetted surface of the hull. It WILL slow you down a tremendous amount! Also consider you have a larger boat, at 27' there is that much more drag to slow you down so I can believe a 15-20 mph top speed, especially if you have an outdrive that's loaded with barnacles as well and also if the prop is loaded with barnacles.<br /><br />if you moor or dock your boat in water all season long, then you must bottom paint it unless you like scraping barnacles. I know exactly what your hull bottom looks like if it's a bare white fiberglass bottom. I have a 24' boat which I bottom painted years ago, but before the bottom paint I had gotten a full bottom of barnacles twice and a boat which normally did 40mph top end didn't get over 25mph nor on plane and only saw 3000-3500 rpm. And last year on my 19' bayliner, thankfully that's bottom painted but just my outdrive got loaded with barnacles which caused the boat not to plane and that normally does 40-45mph at 4800 rpm but was reduced to 30mph and a top rpm of 3500.<br /><br />your engine is probably completely fine, your just working the p1ss out of it. Your wasting your time doing anything other than pulling the boat and cleaning the entire running surface of the hull. And your stupid if you don't bottom paint it before putting it back in the water.

 

[I/O WALDO]

Re: boat will not plane out!!!

Are you sure the trailer is nott still under it!! :

 

[bamadave]

Re: boat will not plane out!!!

Waldo, that only happens to blondes, lol!

 

[calwldlif]

Re: boat will not plane out!!!

I/O Waldo <br />

 

[Purduebarry]

Re: boat will not plane out!!!

When he said barnacles I figured a little crud, re-reading this makes me thing he has seaworld stuck on the bottom! Clean it and please tell me you don't have two year old gas in the tank! That should have been your first thread.

 

[jaybirdhi]

Re: boat will not plane out!!!

thanks everyone for your posts. I have already ran two tanks of gas through it as well as changed the filter and treated it with sea foam. i have now added an octane booster but no help. the first time i put in in the water was may 1st. yes i actually did have it up to about 48mph or so. its a 460 but its worked up pretty good. guy i bought it from told me the engine is putting out about 475 horse. who knows right now i would be happy to hit 40 mph. anyway it has been getting worse and worse so it would lead me to believe that it is the barnacle problem. half the people i ask tell me that there is no way barnacles can slow the boat down from 50 to 15. right now i believe it is. tomorrow i will climb in the dirty *** hudson river and scrape the bottom just to see if thats the problem. hopefully it is and i will spend this weekend powerwashing and painting. if it helps the rps will hit about 4800 in nuetral and maxes out at about 3300 in gear. i cant believe how fast the barnacles can take over the bottom of my boat. by the way very few barnacles on the outdrive and none on the prop.

 

[Purduebarry]

Re: boat will not plane out!!!

speaking of prop I assume you checked it, not spun?

 

[jaybirdhi]

Re: boat will not plane out!!!

if the prop was spun then the rpm's would jump like a cluch in car slipping right??

 

[Purduebarry]

Re: boat will not plane out!!!

No, you would get major slipage, depending on the type of prop and hub configuration you would get slipage under heavy load. When you go to high RPM's, you go nowhere fast. When at low RPM's the prop seems fine because there is very little load. <br /><br />I've never had a worn clutch "jump". The RPM's keep climbing but you don't go any faster, there is no jump. If the hub fails complelty the prop can shear off, then your really screwed. Maybe someone else can explain this better or how to test for it!