No acceleration on a 5.0 Volvo penta Sx Cobra

czardog

Recruit
Joined
Jul 26, 2018
Messages
3
We have a 1999 Regal 2100 with the Volvo Penta V8 5.0. with about 200 hours on it.

We've had acceleration issues since day 1 and i'm absolutely at wits end trying to figure this out.

Pulling out a skier is absolute torture for anyone who is willing to suffer through10 + seconds of the boat getting out of the water. Any reviews of this model boat show that this boat actually gets out of the water very quickly, even with the v6 option. So this isn't a normal characteristic for this boat.

If you simply drop the throttle to go like you would on other boats, you will hear the rpms rise rise and then drop. To get the most of the engine you have to gradually ease the accelerator, if you increase throttle too quickly rpms will drop.

The boat is super fast once it's going, i've gps it close to 60 mph. It's simply an acceleration issue.

I'm on my third propeller but nothing has changed expect now i have lower top speed.

Mechanics can't come up with another solution other than tune ups and propellers but nothing seems to work. Mind you all of them have been mercuriser mechanics as there isn't a Volvo mechanic near us. all of them are scratching there heads with no solution.

Any help would be great appreciated
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
51,201
is the motor stumbling as you quickly give it throttle? if so, get a carb kit and fix the accelerator pump
 

czardog

Recruit
Joined
Jul 26, 2018
Messages
3
Welcome Aboard!

What are the specs on the propeller you have?

I'm away from the boat now, but if i recall correctly we tried 17, 19, 21 pitch propellers with multiple mechanics and we all concluded that it wasn't propeller related.
 

czardog

Recruit
Joined
Jul 26, 2018
Messages
3
is the motor stumbling as you quickly give it throttle? if so, get a carb kit and fix the accelerator pump

Not necessarily stumbling, still idles and revs smoothly, it simply drops rpms if you throttle too quickly. And if it doesn't drop it just takes long for the boat to plane but the engine still sounds to rev normally with out any hiccups.

Also i was under the impression that this motor was EFI. didn't think it had a carb!`
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
51,201
pull the spark arrestor and look.

its either a carb, throttle body EFI or Multi-Port Injection.

however most boats from the late 90's were still carb.
 
Top