1978 tahiti 16 ft inboard

[tsmfudge]

I have a Tahiti 16 ft inboard boat. The boat has a Volvo Penta AQ130d engine and the outdrive is a Volvo Penta 270 with a 17 pitch prop. The boat starts great and in Neutral I can rev the engine to as high as I want to 6000 RPM,s. But when I put it into drive and give it full throttle I can only get 3000 RPM,s which is not enough to level the boat out on the water. I checked the compression and it is 120 in each cylinder. I am not sure why I can't get more RPM,s out of the engine in drive. Can someone give me some good advice on what the problem is and how to fix it.
Thanks
tsmfudge

 

[alldodge]

Re: 1978 tahiti 16 ft inboard

:welcome: to iboats

The engine uses no gas hardly at all in neutral when revving, it takes a whole bunch to rev up unload. Have you replaced the fuel filters, if not do so. Check all fuel lines for restrictions. Put a fuel pressure gauge between the fuel pump and carb, should be between 4 and 7 psi.

 

[steelespike]

Re: 1978 tahiti 16 ft inboard

Welcome
I think you will get more successful results in the Volvo I/O forum.

 

[jerryjerry05]

Re: 1978 tahiti 16 ft inboard

Welcome,
The prop is it the OEM or a replacement?
Pics?
The drive any work done?
Could be fuel related?
Possibly the coil?
The distributor not advancing?

 

[tsmfudge]

Volvo Penta AQ130D

Volvo Penta AQ130D

I have a 1978 Tahiti trihull 16 ft inboard. I am having trouble getting above 3000 rpm,s in drive.When it is in neutral I can rev it up as high as I want but when I put it in drive I can only get it up to 3000 with full throttle. I checked compression and it has 120 in each cylinder. The prop is a 14X17L. I think it is original it is a volvo prop. I am at a loss for coming up with a solution to the problem. Let me know if anyone else had the same problem and how they solved it.
Thanks
tsmfudge

 

[tsmfudge]

volvo penta AQ130D with a volvo penta 270 outdrive

volvo penta AQ130D with a volvo penta 270 outdrive

I have a 1978 tahiti 16 ft tri hull. I am having problems in getting the boat past 3000 rpm,s in drive. when I have it in neutral I can increase the rpm,s to 6000 or whatever but when I put it in drive with full throttle I get 3000. I checked compression and it is 120 in all four cylinders. It has a 14X17L prop from volvo.I am at 6000 ft elevation The outdrive is a 270 vovlo penta. What is the problem?
Thanks
tsmfudge

 

[Howard Sterndrive]

Re: Volvo Penta AQ130D

Re: Volvo Penta AQ130D

One of the most common symptoms in boating.
here's Don S's master list for diagnosing low wot rpm under way:
http://forums.iboats.com/mercruiser...ives/list-possible-causes-low-wot-295070.html

 

[Howard Sterndrive]

Re: Volvo Penta AQ130D

Re: Volvo Penta AQ130D

p.s.- don't rev it wildly in neutral. Any engine running on half the cylinders can rev up with no load. That's testing nothing and could put the engine at risk.

 

[Bondo]

Re: volvo penta AQ130D with a volvo penta 270 outdrive

Re: volvo penta AQ130D with a volvo penta 270 outdrive

I have a 1978 tahiti 16 ft tri hull. I am having problems in getting the boat past 3000 rpm,s in drive. when I have it in neutral I can increase the rpm,s to 6000 or whatever but when I put it in drive with full throttle I get 3000. I checked compression and it is 120 in all four cylinders. It has a 14X17L prop from volvo.I am at 6000 ft elevation The outdrive is a 270 vovlo penta. What is the problem?
Thanks
tsmfudge

Ayuh,.... Welcome Aboard,.... Yer answers is in Here,...

Here is a list of possible causes of low WOT (Wide Open Throttle) rpm.

In no particular order

Engine Won't Reach Operating RPM. Check

1. Fuel condition. Type and Octane possibly old fuel
2. Propeller pitch or diameter, damaged blades
3. Restricted fuel pickup tube or anti siphon valve Fuel System Test
4. Crankcase oil volume, high oil level can cause aerated oil and lifter collapse
5. Marine growth on hull and outdrive
6. Wrong gear ratio in outdrive
7. Restricted carburetor air intake (clogged flame arrestor)
8. Restricted exhaust system (broken exhaust shutters/flappers) in engine transom shield or drive
9. Poor cylinder compression Compression Test
10. Carburetor defective, or wrong type.
11. Fuel pump pressure and vacuum
12. Boat overloaded, improperly loaded, or improperly trimmed.
13. Engine Overheating
14. Engine timing and ignition system operation
15. Remote control cables and linkage for proper travel to open throttle plates fully.

'n Btw,.....
Post yer question Only Once, in Only One forum,....
Once posted, continue to post in the Same thread, do Not start a new thread each time you post,...

Thank you,...