| Author |
Message |
    
Mitch White
New member
Username: horse_up
Post Number: 1
Registered: 06-2009
| | Posted on Monday, June 29, 2009 - 08:10 am: | 
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I have an AQ131A in an 86 Capri 19 foot boat. How fast should I be going, because I can barely squeeze 32MPH out of it. It takes like a minute to get on plane with the outdrive set at the middle notch. It tachs up good. Also, when feathering the throttle it will seem to choke down until it picks up the fuel and then its ok. But it just seems like I should be getting more power and speed than what I am getting. I have new points, cleaned carb, Fuel system cleaned with new filter. Any Ideas? |
Robert A. Fierro
Advanced Member
Username: sandkicker
Post Number: 646
Registered: 06-2008
| | Posted on Monday, June 29, 2009 - 10:20 am: |
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Re: "tachs up good"...
If by that you mean that it gets to at least 4700 RPM (but not over 5000), then all is OK.
You MAY be able to change the prop and squeek another mph or 2 out of it but that's it.
That engine is a 120HP engine. 30ish is about all you'll get with a 120HP engine on a 19 ft boat (unless the boat hull is flat bottomed which the Capri isn't). It takes a surprising amount of HP to push a boat much over 30.
Also... running a marine engine continuouly at WOT is a recipe for a new engine. Volvo recommends that continuous operating RPM be no more that 300 to 500 below max RPMs. I feel that this is a bit optimistic. For best engine life I'd limit continuous RPMs to 80% of max. |
J.C.H.
Advanced Member
Username: ruckus3313
Post Number: 104
Registered: 10-2008
| | Posted on Monday, June 29, 2009 - 10:43 am: |
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mitch,
just to give you an idea my aq125a w/270 outdrive on a 17.6 ft boat tops off at 31mph with just me and a full tank. ill get 32mph out of her with a half tank of fuel. my prop is a 14x17 volvo penta p#814632. This older v/p aq engines are not power monsters but I have learned that they are very reliable and are very torquey!!! even with 6 people in my boat i can still turn about 26-27mph. |
Robert A. Fierro
Advanced Member
Username: sandkicker
Post Number: 647
Registered: 06-2008
| | Posted on Monday, June 29, 2009 - 11:13 am: |
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Further JCH's comment. I used to have an AQ120 on an 18 ft Deep V. Other than a starter and an alternator replacement, the engine was bullet proof. It was also VERY fuel efficient...if run at 75 to 80% of WOT RPMs. |
J.C.H.
Advanced Member
Username: ruckus3313
Post Number: 105
Registered: 10-2008
| | Posted on Monday, June 29, 2009 - 02:36 pm: |
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robert is correct on this mitch. very reliable and unbelieveable fuel economy. i as well try to keep cruising rpm's in between 4000-4300 rpm.when others are burning 100 dollars worth of fuel i have gone through about 35 dollars worth!! |
