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VP 270 outdrive

M

my_heap

Contributing Member
Top speed is 10-12 MPH with AQ

Top speed is 10-12 MPH with AQ 151
Boat is 26' Foot Explorer.
I have seen other Explorers running AQ 131 and topping out at 18 MPH some claim 22 MPH.
Now I am wondering if I may have wrong prop.
If someone knows proper pitch I need for more top speed. I run in the River so dont really need much low end tourqe.
 
"The right propeller is the on

"The right propeller is the one that allows your boat to plane and with which the engine can reach the maximum recommended RPM. Your engine is supposed to reach between 4800 and 5500 RPM. If it cannot reach them, then you are overpropped.

What are the maximum RPM your engine can reach now and what size of prop do you have installed?"
 
It does not look much like a &

It does not look much like a 'planning' boat to me. In that case I would have modified the prop-shaft with center bolt and long hub cone and gone for a 15" wide-blade or even 16". Might have to be modified to avoid conflict with the exhaust outlet. Pitch not above 13".
 
"True, it is either a displace

"True, it is either a displacement or a semi-displacement hull (depending on who you listen to). So let's ignore the "planing" part of my post."
 
"CS, your question is difficul

"CS, your question is difficult because of the problem of verifying a number of points. For one thing, there is no easy answer as to the type of hull of the Bayliner Explorer. It appears to be a semi displacement type which displays neither true planing nor true displacement characteristics. A displacement hull of that length could probably achieve 8 mph with about 30 hp. It would appear that the speed of your boat could be increased slightly by tinkering with props and/or by getting the bow down a couple degrees. This might also help "high speed" steering although I question whether any measure will modify the well known Explorer wandering at speeds below about 9 mph. This argues for the highest speed possible and a stated top speed of 12 mph sounds about right to me. Conjecturing a speed of 22 mph is fantastical, IMO. I doubt that more than 12-14 mph can be achieved with a boat which weighs almost 3 tons including a full load of passengers. The hull does not appear to be designed for this with the power available."
 
"El Pescador I am not by my bo

"El Pescador I am not by my boat but the prop looks kinda small. I will check the numbers next time I go by the Marina.
As far as top speed I have never had my current engine at WOT. 4,000 RPM is all I wound it up to.
The AQ 120 WOT the tach was not working but top speed was 9 MPH according to my GPS.
I have another outdrive that came with my engine but it is a much bigger prop that propelled a 50' foot houseboat."
 
I just saw an 2670 Explorer on

I just saw an 2670 Explorer on Ebay and the guy is saying a 15x17 pitch prop does this sound right? I cant see my boat today as it is stored 30 miles away at a marina
 
"Cameron, according to the Mic

"Cameron, according to the Michigan prop table (page 58 on the link)

http://www.miwheel.com/MIWheel/pdf/obsd_03.pdf

it seems that a 15x17 would be too big for a 26-27' boat. with an AQ151 But again, the only way to find out is to try to reach the maximum engine RPM withthat propeller. If you get 4800-5500 RPM, then the prop size is correct, but that doesn't mean it is the most efficient for your application. In addition to pitch and diameter, there are factors like blade width, rake, cup, etc that can have a dramatic effect in performance.

Page 5 in the above link gives you some guidelines to determine the correct size of a propeller for your application."
 
"A 14 X 17 prop should give ab

"A 14 X 17 prop should give about 5000 rpm which is max recommended for a boat of the Explorer's type. Volvo allows 5500 rpm for ski boats or other small craft but would not normally be suitable for the Explorer. In this size range, I believe large diameter props are more efficient for slow turning, high torque powerplants and displacement hulls. However, your present prop size is needed for reference. "
 
"17" prop (pitch)

"17" prop (pitch) is faaaaar to heavy on that app. If using Michigan, go by 15" x 13".
A 13 inch will nominally give 25knots without slip at 5000 rpm. With the boat concerned I doubt You'll manage much above 4500 and 15-18 knots at top, light boat. What You'll need is minimum pitch and max blade-area."
 
My volvo 5 l gxi one year old

My volvo 5 l gxi one year old also missfire from old petrol. I change from outboards to inboard with duelprops. Can I trust the enjin to go out 20 miles or more on open sea ? If I read all the problems with inboards?
Andrew
 
"Pieter, get some fresh petrol

"Pieter, get some fresh petrol, a full set of tools and parts and head out to sea without fear.

Morton, I have little experience with the pitch problem but here is what happened once upon a time. My boat is about the same size and weight as the Explorer, or a tad larger, but is a planing boat with 22 deg deadrise. It is equipped with two Volvo 2.5 liter, OHC engines. Currently, the drives are propped 14 X 19. However, the first year after powering up with these engines the props were 14 X 17. A water pump problem caused me to shut down the strbd engine. I returned to the barn, a distance of 20 miles, on one engine. By no stretch of the imagination could one engine drive that boat at 18 knots (which is planing speed) regardless of propeller size or pitch. However, with the 17 pitch prop, the engine could pull 4500+ rpm and the boat would wallow along at about 12 mph. I didn't ram the throttle to the stop but could have gotten another one or two mph, and 5000 rpm max, I suppose."
 
"Hi,
my boat is an 18 footer

"Hi,
my boat is an 18 footer weighing approx 1.5 tons and equipped with an AQ151C / 290 / 15x17 aluminium prop. She's normally out of the hole like a startled rabbit but I have never seen anything above 4000 rpm at WOT. Is she over propped? This prop is what was supplied with the package from new."
 
Just bought 18.6' 79 Bayli

Just bought 18.6' 79 Bayliner Quartermaster W/ Volvo 270.
First outing and the down tilt on outdrive quit.
The up tilt still works.
What is best plan for diagnosis and repair?
 
"Sounds like either one of the

"Sounds like either one of the relays is not working; or one of the wires is broken, loose or has a rusty connection. Hopefully, it is not a problem with the tilt motor itself. You may want to download the manual for the AQ240 from VP, which has a good electrical drawing of the tilt system:

http://www.volvo.com/volvopenta/global/en-gb/marineengines/operators_manual/

Also, my apologies for the wrong link in the previous message, as I have no clue how it showed up there. This is the correct one:

http://www.volvopentastore.com/ENGINE_SPEED_CONTROL_AQ145B/dm/store_id.366--sess ion_id.264904798--cart_id.443433535--category_id.331776--list_time.1191785712--v iew_id.327022"
 
"Thanks for the info...ckd out

"Thanks for the info...ckd out and down relay is suspect. We will know tomorrow if this is the fix, also motor is fine."
 
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