volvo penta AQ125a wont get over 2000 rpms when in gear

[beanomuntz]

I have a 1983 bayliner with a AQ125a. When in neutrel it will rev as many rpms as you want but when i put it in gear i can only get 2000 rpms out of it. I thought that maybe the high speed jet in the carburator was bad but Im not sure was just wondering if any one had any suggestions.

 

[88wellcraft]

Re: volvo penta AQ125a wont get over 2000 rpms when in gear

on muffs...or in the water under load?

 

[Don S]

Re: volvo penta AQ125a wont get over 2000 rpms when in gear

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.

 

[beanomuntz]

Re: volvo penta AQ125a wont get over 2000 rpms when in gear

I cleaned up the spark plugs and then went through the fuel system and made sur it wasnt clogged up one of the spark plugs was pretty bad. I got it all back to gather and it seems to run fine now. Not sure if it was the spark plug or if I had a little something in the fuel system but whatever it was its fixed. thanks for your help

 

[alex081953]

Volvo Penta 5.7 GSi, cann't get more then 2400 RPM, how to check exhast flappers

Volvo Penta 5.7 GSi, cann't get more then 2400 RPM, how to check exhast flappers

Hi, I have a Volvo Penta 1999 FI. After replacing a broken impeller tested a boat on the water. It ran fine for 20 min, then I stopped for 10-15 min and on the way back RPM couldn't get more than 2400. Motor starts and idle fine, temperature and oil pressure are normal. After I disengaged the outdrive, I was able to increase RPM up to 4000, but then I heard a backfire and exhaust riser disconnected from rubber hose.
I do not have any idea where to look first and how to find a problem. I?m in Russia and I do not have a mechanic who could help me to fix it.

 

[jimedac]

Re: Volvo Penta 5.7 GSi, cann't get more then 2400 RPM, how to check exhast flappers

Re: Volvo Penta 5.7 GSi, cann't get more then 2400 RPM, how to check exhast flappers

Check the exhaust flappers restricted exhaust

 

[alex081953]

Re: Volvo Penta 5.7 GSi, cann't get more then 2400 RPM, how to check exhast flappers

Re: Volvo Penta 5.7 GSi, cann't get more then 2400 RPM, how to check exhast flappers

Check the exhaust flappers restricted exhaust

It could be a stupid question, but how to check the flappers?